Perseverance rover explores Bright Angel in ancient riverbed

View larger. | NASA’s Perseverance rover captured this view of the light-toned rock outcrop Bright Angel on June 16, 2024. Image via NASA/ JPL-Caltech.

• NASA’s Perseverance rover reached rock outcrops called Bright Angel, in an ancient river channel known as Neretva Vallis.
• The outcrops may be either ancient rock exposed by river erosion or sediments that filled the channel.
• Bright Angel is the latest science target in Neretva Vallis. The rover also investigated an unusual rock called Atoko Point.

Perseverance rover explores an ancient riverbed

NASA’s Perseverance rover has been busy investigating an ancient river channel on Mars called Neretva Vallis. It lies alongside the inner wall of Jezero crater. The channel, with sand dunes, boulders and rocky outcrops, is chock full of geologically exciting features. On June 13, 2024, NASA said the rover reached its latest target, Bright Angel. The light-toned rocky outcrops in Bright Angel are distinct among the surrounding darker rocks and sand dunes. The mission team said the outcrops are likely either rock exposed by past river erosion or sediments that once filled the channel.

Along the way, the rover also saw an intriguing white speckled boulder called Atoko Point. It contains pyroxene and feldspar minerals and may have formed in ancient hot magma.

Perseverance rover reaches Bright Angel

In order to reach Bright Angel, Perseverance had to cross the floor of the river channel. Bright Angel appears as a lighter patch inside the channel. The rover reached Bright Angel on June 9, after meandering around some sand dunes and avoiding larger boulders.

This route was shorter than the one the mission team was originally going to take. Overall, it cut the drive time down by several weeks.

Bright Angel is just the latest stop in the Perseverance rover’s 4th science campaign. Perseverance is looking for carbonate and olivine deposits within the Margin Unit, which Bright Angel is part of.

A route change on my way to Bright Angel has led me through an unexpectedly diverse geological playground, Neretva Vallis! This ancient river channel – which carried most of the water that flowed into Jezero Crater billions of years ago – is filled with intriguing boulders. pic.twitter.com/4faWzFZJpt

— NASA's Perseverance Mars Rover (@NASAPersevere) June 13, 2024

Having scooted across Neretva Vallis, @NASAPersevere is now studying an area of light-toned rocks called "Bright Angel". Here's a close-up of the rocks… Geologists, feel free to tell us what you think we're seeing here… Image Credit: NASA/JPL-Caltech/ASU/S Atkinson pic.twitter.com/gIRTl8m8de

— Stuart Atkinson (@mars_stu) June 23, 2024

Navigating rough terrain

Perseverance first drove along a ridge alongside the channel. It wasn’t always an easy trip, however. Evan Graser, Perseverance’s deputy strategic route planner lead at NASA’s Jet Propulsion Laboratory in Southern California, said:

We started paralleling the channel in late January and were making pretty good progress, but then the boulders became bigger and more numerous. What had been drives averaging over a hundred meters per Martian day went down to only tens of meters. It was frustrating.

Perseverance has technological tools to help it navigate rough terrain. It can use its cameras to plan drives of up to 100 feet (30 meters) at a time. But to go farther, it uses its auto-navigation system called AutoNav. In this case, however, the boulders began to become more numerous than anticipated. AutoNav detected them but would make the rover stop as a precaution. That slowed down the rover’s travel’s considerably.

Crossing the river channel

Consequently, the mission team decided to cut across the river channel instead. They had to navigate a 1,300-foot (400-meter) dune field, but that was easier than avoiding the boulders. Graser said:

We had been eyeing the river channel just to the north as we went, hoping to find a section where the dunes were small and far enough apart for a rover to pass between, because dunes have been known to eat Mars rovers. Perseverance also needed an entrance ramp we could safely travel down. When the imagery showed both, we made a beeline for it.

View larger. | The Neretva Vallis river channel as seen by Perseverance on June 6, 2024. Bright Angel is the lighter patch on the right side of the image. Image via NASA/ JPL-Caltech.

View larger/full image. | The bright boulder Atoko Point stands out among the surrounding darker rocks and boulders on Mount Washburn. Perseverance took this photo on May 27, 2024. Image via NASA/ JPL-Caltech/ ASU/ MSSS.

Atoko Point: Perseverance rover finds unusual white boulder

One of the most interesting discoveries that Perseverance made while journeying to Bright Angel was an interesting white boulder that stood out from all the others around it. It was on a small hill called Mount Washburn, which is covered in rocks and boulders. The mission team nicknamed it Atoko Point. The light-colored speckled rock looked distinctly different from the other reddish rocks. What was it? Brad Garczynski at Western Washington University in Bellingham said:

The diversity of textures and compositions at Mount Washburn was an exciting discovery for the team, as these rocks represent a grab bag of geologic gifts brought down from the crater rim and potentially beyond. But among all these different rocks, there was one that really caught our attention.

View larger. | Map of Perseverance’s path through the ancient river channel Neretva Vallis from January 21 to June 11, 2024. Image via NASA/ JPL-Caltech/ University of Arizona.

Ancient subsurface magma?

Atoko Point is 18 inches (45 cm) wide and 14 inches (35 cm) tall. It kind of looked like granite, but what was it actually made of? Analysis by Perseverance showed it is composed of the minerals pyroxene and feldspar. It’s also unique regarding its size, shape and arrangement of the mineral grains and crystals in it, and maybe even its chemical composition. It’s the first of its kind the rover has seen on Mars.

It may have formed in a subsurface body of hot magma in Jezero crater. Or it could have formed elsewhere, and then one of the ancient rivers of the region transported it to its current location.

After finishing at Mount Washburn, Perseverance traveled 433 feet (132 m) to Tuff Cliff. After that, it made the final leg of the journey to Bright Angel, covering 1,985 feet (605 m).

Bottom line: NASA’s Perseverance rover on Mars has reached an area of flat light-toned rocky outcrops called Bright Angel. The intriguing rocks are in an ancient river channel.

Via NASA

Read more: Perseverance rover reveals history of ancient habitable lake

Read more: 10 months of Perseverance: New Mars discoveries

The post Perseverance rover explores Bright Angel in ancient riverbed first appeared on EarthSky.

from EarthSky https://ift.tt/vwZUj3L

View larger. | NASA’s Perseverance rover captured this view of the light-toned rock outcrop Bright Angel on June 16, 2024. Image via NASA/ JPL-Caltech.

• NASA’s Perseverance rover reached rock outcrops called Bright Angel, in an ancient river channel known as Neretva Vallis.
• The outcrops may be either ancient rock exposed by river erosion or sediments that filled the channel.
• Bright Angel is the latest science target in Neretva Vallis. The rover also investigated an unusual rock called Atoko Point.

Perseverance rover explores an ancient riverbed

NASA’s Perseverance rover has been busy investigating an ancient river channel on Mars called Neretva Vallis. It lies alongside the inner wall of Jezero crater. The channel, with sand dunes, boulders and rocky outcrops, is chock full of geologically exciting features. On June 13, 2024, NASA said the rover reached its latest target, Bright Angel. The light-toned rocky outcrops in Bright Angel are distinct among the surrounding darker rocks and sand dunes. The mission team said the outcrops are likely either rock exposed by past river erosion or sediments that once filled the channel.

Along the way, the rover also saw an intriguing white speckled boulder called Atoko Point. It contains pyroxene and feldspar minerals and may have formed in ancient hot magma.

Perseverance rover reaches Bright Angel

In order to reach Bright Angel, Perseverance had to cross the floor of the river channel. Bright Angel appears as a lighter patch inside the channel. The rover reached Bright Angel on June 9, after meandering around some sand dunes and avoiding larger boulders.

This route was shorter than the one the mission team was originally going to take. Overall, it cut the drive time down by several weeks.

Bright Angel is just the latest stop in the Perseverance rover’s 4th science campaign. Perseverance is looking for carbonate and olivine deposits within the Margin Unit, which Bright Angel is part of.

A route change on my way to Bright Angel has led me through an unexpectedly diverse geological playground, Neretva Vallis! This ancient river channel – which carried most of the water that flowed into Jezero Crater billions of years ago – is filled with intriguing boulders. pic.twitter.com/4faWzFZJpt

— NASA's Perseverance Mars Rover (@NASAPersevere) June 13, 2024

Having scooted across Neretva Vallis, @NASAPersevere is now studying an area of light-toned rocks called "Bright Angel". Here's a close-up of the rocks… Geologists, feel free to tell us what you think we're seeing here… Image Credit: NASA/JPL-Caltech/ASU/S Atkinson pic.twitter.com/gIRTl8m8de

— Stuart Atkinson (@mars_stu) June 23, 2024

Navigating rough terrain

Perseverance first drove along a ridge alongside the channel. It wasn’t always an easy trip, however. Evan Graser, Perseverance’s deputy strategic route planner lead at NASA’s Jet Propulsion Laboratory in Southern California, said:

We started paralleling the channel in late January and were making pretty good progress, but then the boulders became bigger and more numerous. What had been drives averaging over a hundred meters per Martian day went down to only tens of meters. It was frustrating.

Perseverance has technological tools to help it navigate rough terrain. It can use its cameras to plan drives of up to 100 feet (30 meters) at a time. But to go farther, it uses its auto-navigation system called AutoNav. In this case, however, the boulders began to become more numerous than anticipated. AutoNav detected them but would make the rover stop as a precaution. That slowed down the rover’s travel’s considerably.

Crossing the river channel

Consequently, the mission team decided to cut across the river channel instead. They had to navigate a 1,300-foot (400-meter) dune field, but that was easier than avoiding the boulders. Graser said:

We had been eyeing the river channel just to the north as we went, hoping to find a section where the dunes were small and far enough apart for a rover to pass between, because dunes have been known to eat Mars rovers. Perseverance also needed an entrance ramp we could safely travel down. When the imagery showed both, we made a beeline for it.

View larger. | The Neretva Vallis river channel as seen by Perseverance on June 6, 2024. Bright Angel is the lighter patch on the right side of the image. Image via NASA/ JPL-Caltech.

View larger/full image. | The bright boulder Atoko Point stands out among the surrounding darker rocks and boulders on Mount Washburn. Perseverance took this photo on May 27, 2024. Image via NASA/ JPL-Caltech/ ASU/ MSSS.

Atoko Point: Perseverance rover finds unusual white boulder

One of the most interesting discoveries that Perseverance made while journeying to Bright Angel was an interesting white boulder that stood out from all the others around it. It was on a small hill called Mount Washburn, which is covered in rocks and boulders. The mission team nicknamed it Atoko Point. The light-colored speckled rock looked distinctly different from the other reddish rocks. What was it? Brad Garczynski at Western Washington University in Bellingham said:

The diversity of textures and compositions at Mount Washburn was an exciting discovery for the team, as these rocks represent a grab bag of geologic gifts brought down from the crater rim and potentially beyond. But among all these different rocks, there was one that really caught our attention.

View larger. | Map of Perseverance’s path through the ancient river channel Neretva Vallis from January 21 to June 11, 2024. Image via NASA/ JPL-Caltech/ University of Arizona.

Ancient subsurface magma?

Atoko Point is 18 inches (45 cm) wide and 14 inches (35 cm) tall. It kind of looked like granite, but what was it actually made of? Analysis by Perseverance showed it is composed of the minerals pyroxene and feldspar. It’s also unique regarding its size, shape and arrangement of the mineral grains and crystals in it, and maybe even its chemical composition. It’s the first of its kind the rover has seen on Mars.

It may have formed in a subsurface body of hot magma in Jezero crater. Or it could have formed elsewhere, and then one of the ancient rivers of the region transported it to its current location.

After finishing at Mount Washburn, Perseverance traveled 433 feet (132 m) to Tuff Cliff. After that, it made the final leg of the journey to Bright Angel, covering 1,985 feet (605 m).

Bottom line: NASA’s Perseverance rover on Mars has reached an area of flat light-toned rocky outcrops called Bright Angel. The intriguing rocks are in an ancient river channel.

Via NASA

Read more: Perseverance rover reveals history of ancient habitable lake

Read more: 10 months of Perseverance: New Mars discoveries

The post Perseverance rover explores Bright Angel in ancient riverbed first appeared on EarthSky.

from EarthSky https://ift.tt/vwZUj3L

Hercules the Strongman and a great globular cluster

The constellation Hercules lies between the bright stars Vega in Lyra and Arcturus in Boötes. A famous globular cluster, known as M13, lies on the Keystone, an asterism in Hercules. Chart via EarthSky.

Hercules (Heracles for the Greeks) is the strong man of ancient Roman mythology. He was a son of Jupiter who had to perform the famous twelve labors. Astronomers know Hercules as a constellation high in the northern sky on June evenings that’s home to an asterism known as the Keystone, where you can find what may be the best globular cluster for Northern Hemisphere observers: M13, or the Great Cluster in Hercules.

Hercules is one of the largest of the 88 constellations, ranking fifth in size.

How to find Hercules

Hercules lies next to the bright star Vega in the constellation Lyra, which lies high in summer skies. Specifically, Hercules lies west of Lyra and east of Boötes with its bright star Arcturus.

Because the stars of Hercules are not particularly bright, it is hard to pick out the constellation. Overall its most distinctive shape is the asterism of the Keystone near the center of the constellation. Generally, Hercules appears somewhat like a pinwheel, with arms of stars emanating outward from its central Keystone shape.

View at EarthSky Community Photos. | Prateek Pandey in Bhopal, Madhya Pradesh, India, captured this photo of Corona Borealis, Hercules and neighbors on April 3, 2021. He wrote: “Hercules and the neighboring constellations in the northeastern sky.” Thank you, Prateek!

Stars of the Strongman

Even though the stars of Hercules are not particularly bright, the Keystone is obvious in dark skies. The brightest star in the Keystone of Hercules is magnitude 2.81 Zeta Herculis, which lies 35 light-years away. At the opposite corner of the Keystone (and the Keystone star closest to Vega) is the magnitude 3.15 star Pi Herculis. Pi Herculis lies 377 light-years away. The northernmost Keystone star is magnitude 3.48 Eta Herculis at 112 light-years. Opposite Eta Herculis and the dimmest of the four Keystone stars is magnitude 3.92 Epsilon Herculis. It lies 155 light-years away.

Additionally, the other two semi-bright stars in Hercules form an arm winding off from Zeta Herculis. The star closest to Zeta Herculis is Beta Herculis, or Kornephoros. It lies 139 light-years away with a magnitude 2.81. And the other bright star lies close to the border with Ophiuchus. It is Alpha Herculis, lying 360 light-years away shining at magnitude 3.48. This star also has the nickname of Rasalgethi. As a matter of fact, Rasalgethi is three stars. The first component is a red giant and the other two are a double star system with a yellow giant and a yellow-white dwarf. The double stars are lovely in a telescope because you’ll see an orange and a blue star.

The stars of Hercules the Strongman. Image via International Astronomical Union/ Sky & Telescope/ Wikimedia Commons/ CC BY 3.0.

Globular clusters in Hercules

Primarily, the real attractions with the Hercules constellation are its two spectacular globular clusters. Both are Messier objects, easy to find in binoculars and a real treat through a telescope.

The first, M13, lies right on the Keystone (although in actuality it is 25,000 light-years away, much farther than the Keystone stars). M13 is 2/3 of the way on a line that stretches between the stars Zeta Herculis and Eta Herculis. It lies just 2 1/2 degrees from Eta. The Great Cluster in Hercules shines at magnitude 5.9, meaning it’s possible to see it as a fuzzy patch with your eye alone from dark sites. When looking at M13, you are looking at the combined light of hundreds of thousands of distant stars.

View at EarthSky Community Photos. | Mario Rana in Hampton, Virginia, captured globular cluster M13 on June 10, 2023. He wrote: “Globular cluster M13 in the constellation Hercules. The object at the bottom left corner is spiral galaxy NGC 6207.” Thank you, Mario!

Another globular cluster in Hercules is M92. M92 makes a triangle with the two northernmost stars in the Keystone. Imagine it as where Hercules’ head would be. M92 lies about 6 1/2 degrees north of Pi Herculis and nearly eight degrees from Eta Herculis. Shining at magnitude 6.5, M92 lies about 26,000 light-years away. You can marginally see it without optical aid, but it shows up easily in binoculars and a telescope.

View at EarthSky Community Photos. | Ron Haggett in Yuma, Arizona, took this image of a globular cluster on January 5, 2022. Ron wrote: “Messier 13 or the Great Globular Cluster in Hercules. Fortunately for me it is viewable around 5 in the morning!” Thank you, Ron!

M92 and the celestial pole

Another key point: 14,000 years from now, the Earth will have wobbled on its axis so that M92 is less than one degree from the north celestial pole at that time. (Read more about the precession and which stars will become the North Star over time at The North Star: Does it ever move?)

You can see in the simulation below that the north celestial pole skirts through Hercules in the bottom left corner of the visualization.

Due to Earth's precession, Polaris, Alderamin, Vega, and Thuban take turns being the North Star every 26,000 years. Due to proper motion, even Arcturus took a turn 58,000 years ago.

Simulation: higher res, more years, including Arcturus' brief reign.https://t.co/le8yOqJ5QV pic.twitter.com/5diNCQsqL6

— Tony Dunn (@tony873004) June 8, 2022

Bottom line: Hercules the Strongman is a great constellation to view in the summer. With only a pair of binoculars you can see the globular cluster M13 in the Keystone.

Read more: M13, the Great Cluster in Hercules

The post Hercules the Strongman and a great globular cluster first appeared on EarthSky.

from EarthSky https://ift.tt/9WsE45p

The constellation Hercules lies between the bright stars Vega in Lyra and Arcturus in Boötes. A famous globular cluster, known as M13, lies on the Keystone, an asterism in Hercules. Chart via EarthSky.

Hercules (Heracles for the Greeks) is the strong man of ancient Roman mythology. He was a son of Jupiter who had to perform the famous twelve labors. Astronomers know Hercules as a constellation high in the northern sky on June evenings that’s home to an asterism known as the Keystone, where you can find what may be the best globular cluster for Northern Hemisphere observers: M13, or the Great Cluster in Hercules.

Hercules is one of the largest of the 88 constellations, ranking fifth in size.

How to find Hercules

Hercules lies next to the bright star Vega in the constellation Lyra, which lies high in summer skies. Specifically, Hercules lies west of Lyra and east of Boötes with its bright star Arcturus.

Because the stars of Hercules are not particularly bright, it is hard to pick out the constellation. Overall its most distinctive shape is the asterism of the Keystone near the center of the constellation. Generally, Hercules appears somewhat like a pinwheel, with arms of stars emanating outward from its central Keystone shape.

View at EarthSky Community Photos. | Prateek Pandey in Bhopal, Madhya Pradesh, India, captured this photo of Corona Borealis, Hercules and neighbors on April 3, 2021. He wrote: “Hercules and the neighboring constellations in the northeastern sky.” Thank you, Prateek!

Stars of the Strongman

Even though the stars of Hercules are not particularly bright, the Keystone is obvious in dark skies. The brightest star in the Keystone of Hercules is magnitude 2.81 Zeta Herculis, which lies 35 light-years away. At the opposite corner of the Keystone (and the Keystone star closest to Vega) is the magnitude 3.15 star Pi Herculis. Pi Herculis lies 377 light-years away. The northernmost Keystone star is magnitude 3.48 Eta Herculis at 112 light-years. Opposite Eta Herculis and the dimmest of the four Keystone stars is magnitude 3.92 Epsilon Herculis. It lies 155 light-years away.

Additionally, the other two semi-bright stars in Hercules form an arm winding off from Zeta Herculis. The star closest to Zeta Herculis is Beta Herculis, or Kornephoros. It lies 139 light-years away with a magnitude 2.81. And the other bright star lies close to the border with Ophiuchus. It is Alpha Herculis, lying 360 light-years away shining at magnitude 3.48. This star also has the nickname of Rasalgethi. As a matter of fact, Rasalgethi is three stars. The first component is a red giant and the other two are a double star system with a yellow giant and a yellow-white dwarf. The double stars are lovely in a telescope because you’ll see an orange and a blue star.

The stars of Hercules the Strongman. Image via International Astronomical Union/ Sky & Telescope/ Wikimedia Commons/ CC BY 3.0.

Globular clusters in Hercules

Primarily, the real attractions with the Hercules constellation are its two spectacular globular clusters. Both are Messier objects, easy to find in binoculars and a real treat through a telescope.

The first, M13, lies right on the Keystone (although in actuality it is 25,000 light-years away, much farther than the Keystone stars). M13 is 2/3 of the way on a line that stretches between the stars Zeta Herculis and Eta Herculis. It lies just 2 1/2 degrees from Eta. The Great Cluster in Hercules shines at magnitude 5.9, meaning it’s possible to see it as a fuzzy patch with your eye alone from dark sites. When looking at M13, you are looking at the combined light of hundreds of thousands of distant stars.

View at EarthSky Community Photos. | Mario Rana in Hampton, Virginia, captured globular cluster M13 on June 10, 2023. He wrote: “Globular cluster M13 in the constellation Hercules. The object at the bottom left corner is spiral galaxy NGC 6207.” Thank you, Mario!

Another globular cluster in Hercules is M92. M92 makes a triangle with the two northernmost stars in the Keystone. Imagine it as where Hercules’ head would be. M92 lies about 6 1/2 degrees north of Pi Herculis and nearly eight degrees from Eta Herculis. Shining at magnitude 6.5, M92 lies about 26,000 light-years away. You can marginally see it without optical aid, but it shows up easily in binoculars and a telescope.

View at EarthSky Community Photos. | Ron Haggett in Yuma, Arizona, took this image of a globular cluster on January 5, 2022. Ron wrote: “Messier 13 or the Great Globular Cluster in Hercules. Fortunately for me it is viewable around 5 in the morning!” Thank you, Ron!

M92 and the celestial pole

Another key point: 14,000 years from now, the Earth will have wobbled on its axis so that M92 is less than one degree from the north celestial pole at that time. (Read more about the precession and which stars will become the North Star over time at The North Star: Does it ever move?)

You can see in the simulation below that the north celestial pole skirts through Hercules in the bottom left corner of the visualization.

Due to Earth's precession, Polaris, Alderamin, Vega, and Thuban take turns being the North Star every 26,000 years. Due to proper motion, even Arcturus took a turn 58,000 years ago.

Simulation: higher res, more years, including Arcturus' brief reign.https://t.co/le8yOqJ5QV pic.twitter.com/5diNCQsqL6

— Tony Dunn (@tony873004) June 8, 2022

Bottom line: Hercules the Strongman is a great constellation to view in the summer. With only a pair of binoculars you can see the globular cluster M13 in the Keystone.

Read more: M13, the Great Cluster in Hercules

The post Hercules the Strongman and a great globular cluster first appeared on EarthSky.

from EarthSky https://ift.tt/9WsE45p

Lyra the Harp contains Vega, a summer gem

The constellation Lyra the Harp. It’s made of a triangle and a parallelogram. Its brightest star is Vega. Then, look next to it for the famous Epsilon Lyrae, a double-double star, really 4 stars in all.

Yes, Lyra is a small constellation, 52nd out of the 88 constellations. But it has a big presence. That’s because its bright star Vega is prominent in northern summer skies and it’s a corner of the famous Summer Triangle star pattern. Vega shines at magnitude 0.03, which makes it the 5th brightest star in Earth’s sky, or the 2nd brightest star belonging to just the Northern Hemisphere. Vega is so bright because it lies just 25 light-years away.

Lyra is described as a harp, lyre or stringed instrument. And it’s one of the constellations that Ptolemy named back in the 2nd century.

How to find Lyra

The easiest way to find Lyra is to look directly overhead on summer evenings in the Northern Hemisphere. The brightest star closest to the zenith on a summer night after the sky gets dark is Vega. It will get closer to the zenith and pass through it as the evening turns to morning.

Once you find Vega, wait until your eyes are dark adjusted so that you can make out the parallelogram dangling below it. Then, when you look back toward Vega, can you trace out a small triangle shape attached to the parallelogram? That star in the small triangle and which is not part of the parallelogram – or Vega – is Epsilon Lyrae, and we’ll get to it later.

Here are the 3 stars of the Summer Triangle, in the east in the evening in July. You can see the outline of Vega’s constellation, Lyra. You can see the Summer Triangle in the evening from around May through the end of the year.

A hotbed of double stars

Now that we’ve met Vega (Alpha Lyrae), let’s meet the other stars in the Harp. The two stars in the parallelogram closest to Vega are the dimmer of the four stars. These two stars are both double stars. The double star directly below Vega is Zeta Lyrae. The stars in this pair have magnitudes 4.34 and 5.73. They lie just 44 arcseconds from each other and 150 light-years away from us. Of course, a telescope can easily split the pair, but a good pair of binoculars may work as well.

The next double star in the parallelogram consists of Delta 1 and 2 Lyrae. The brighter star has magnitude 4.22, and the dimmer is of magnitude 5.58. They lie 10 arcminutes from each other, so you can easily split them in binoculars. The Delta 1 and 2 stars lie 1,080 and 898 light-years away, respectively.

Finally, the last double hovering around Vega is Epsilon Lyrae, which completes the small triangle near Vega. Epsilon Lyra is more famously known as the Double Double. A telescope reveals that this double star is actually a quadruple system. Epsilon 1 lies 3 1/2 arcminutes from Epsilon 2. The Epsilon 1 stars have magnitudes 4.7 and 6.2, and the Epsilon 2 stars have magnitudes 5.1 and 5.5. This multiple star system lies about 160 light-years away.

A photo of Epsilon Lyrae, the Double-Double star in the constellation Lyra the Harp. See how each component in this double star system is also 2 stars? Image via Nikolay Nikolov/ Wikimedia Commons.

The rest of the stars of the Harp

Next, continuing on down to the bottom of the parallelogram, we find the stars Beta Lyrae, or Sheliak, and Sulafat, or Gamma Lyrae. Sulafat is the star farthest from Vega. It shines at magnitude 3.25 at a distance of 635 light-years. Sheliak is the last star in the parallelogram and – surprise! – it is also a double star. The main star has a magnitude of 3.52 and its companion is of magnitude 7.14. You can split this eclipsing binary in large telescopes.

The stars of Lyra. Vega is represented by the large black circle, indicating its brightness relative to other stars. Image via IAU/ Sky & Telescope/ Wikimedia Commons.

Deep-sky objects in Lyra

Two Messier objects reside in Lyra. First, is a planetary nebula, M57, also known as the Ring Nebula. Without a doubt, it’s one of the most observed objects of its type in the sky. It shines at magnitude 9.0 from about 2,300 light-years away. Luckily, it’s easy to find by looking between the bottom two stars of the parallelogram, Sheliak and Sulafat. Use a telescope to catch its oval glow.

View at EarthSky Community Photos. | Michael Terhune in Lunenburg, Massachusetts, captured this telescopic view of Messier 57, the Ring Nebula, on June 18, 2022. Michael wrote: “Here is a really bright beautiful target known as the Ring Nebula or M57 located in the constellation Lyra. Was really happy I was able to pick up the distant background galaxy as well!” Thank you, Michael!

Then a little more than halfway from Sulafat, the bottom star in the parallelogram, and Albireo, the bright double star at the end of Cygnus, you’ll find M56, a loose globular cluster. M56 is a magnitude 8.3 grouping orbiting the Milky Way, lying almost 33,000 light-years away.

M56 is a globular cluster in Lyra. Image via Hunter Wilson/ Wikimedia Commons.

Bottom line: Lyra the Harp is a constellation that hosts the second brightest star in the northern sky, Vega. Look for it on summer nights.

The post Lyra the Harp contains Vega, a summer gem first appeared on EarthSky.

from EarthSky https://ift.tt/pGHIvCm

The constellation Lyra the Harp. It’s made of a triangle and a parallelogram. Its brightest star is Vega. Then, look next to it for the famous Epsilon Lyrae, a double-double star, really 4 stars in all.

Yes, Lyra is a small constellation, 52nd out of the 88 constellations. But it has a big presence. That’s because its bright star Vega is prominent in northern summer skies and it’s a corner of the famous Summer Triangle star pattern. Vega shines at magnitude 0.03, which makes it the 5th brightest star in Earth’s sky, or the 2nd brightest star belonging to just the Northern Hemisphere. Vega is so bright because it lies just 25 light-years away.

Lyra is described as a harp, lyre or stringed instrument. And it’s one of the constellations that Ptolemy named back in the 2nd century.

How to find Lyra

The easiest way to find Lyra is to look directly overhead on summer evenings in the Northern Hemisphere. The brightest star closest to the zenith on a summer night after the sky gets dark is Vega. It will get closer to the zenith and pass through it as the evening turns to morning.

Once you find Vega, wait until your eyes are dark adjusted so that you can make out the parallelogram dangling below it. Then, when you look back toward Vega, can you trace out a small triangle shape attached to the parallelogram? That star in the small triangle and which is not part of the parallelogram – or Vega – is Epsilon Lyrae, and we’ll get to it later.

Here are the 3 stars of the Summer Triangle, in the east in the evening in July. You can see the outline of Vega’s constellation, Lyra. You can see the Summer Triangle in the evening from around May through the end of the year.

A hotbed of double stars

Now that we’ve met Vega (Alpha Lyrae), let’s meet the other stars in the Harp. The two stars in the parallelogram closest to Vega are the dimmer of the four stars. These two stars are both double stars. The double star directly below Vega is Zeta Lyrae. The stars in this pair have magnitudes 4.34 and 5.73. They lie just 44 arcseconds from each other and 150 light-years away from us. Of course, a telescope can easily split the pair, but a good pair of binoculars may work as well.

The next double star in the parallelogram consists of Delta 1 and 2 Lyrae. The brighter star has magnitude 4.22, and the dimmer is of magnitude 5.58. They lie 10 arcminutes from each other, so you can easily split them in binoculars. The Delta 1 and 2 stars lie 1,080 and 898 light-years away, respectively.

Finally, the last double hovering around Vega is Epsilon Lyrae, which completes the small triangle near Vega. Epsilon Lyra is more famously known as the Double Double. A telescope reveals that this double star is actually a quadruple system. Epsilon 1 lies 3 1/2 arcminutes from Epsilon 2. The Epsilon 1 stars have magnitudes 4.7 and 6.2, and the Epsilon 2 stars have magnitudes 5.1 and 5.5. This multiple star system lies about 160 light-years away.

A photo of Epsilon Lyrae, the Double-Double star in the constellation Lyra the Harp. See how each component in this double star system is also 2 stars? Image via Nikolay Nikolov/ Wikimedia Commons.

The rest of the stars of the Harp

Next, continuing on down to the bottom of the parallelogram, we find the stars Beta Lyrae, or Sheliak, and Sulafat, or Gamma Lyrae. Sulafat is the star farthest from Vega. It shines at magnitude 3.25 at a distance of 635 light-years. Sheliak is the last star in the parallelogram and – surprise! – it is also a double star. The main star has a magnitude of 3.52 and its companion is of magnitude 7.14. You can split this eclipsing binary in large telescopes.

The stars of Lyra. Vega is represented by the large black circle, indicating its brightness relative to other stars. Image via IAU/ Sky & Telescope/ Wikimedia Commons.

Deep-sky objects in Lyra

Two Messier objects reside in Lyra. First, is a planetary nebula, M57, also known as the Ring Nebula. Without a doubt, it’s one of the most observed objects of its type in the sky. It shines at magnitude 9.0 from about 2,300 light-years away. Luckily, it’s easy to find by looking between the bottom two stars of the parallelogram, Sheliak and Sulafat. Use a telescope to catch its oval glow.

View at EarthSky Community Photos. | Michael Terhune in Lunenburg, Massachusetts, captured this telescopic view of Messier 57, the Ring Nebula, on June 18, 2022. Michael wrote: “Here is a really bright beautiful target known as the Ring Nebula or M57 located in the constellation Lyra. Was really happy I was able to pick up the distant background galaxy as well!” Thank you, Michael!

Then a little more than halfway from Sulafat, the bottom star in the parallelogram, and Albireo, the bright double star at the end of Cygnus, you’ll find M56, a loose globular cluster. M56 is a magnitude 8.3 grouping orbiting the Milky Way, lying almost 33,000 light-years away.

M56 is a globular cluster in Lyra. Image via Hunter Wilson/ Wikimedia Commons.

Bottom line: Lyra the Harp is a constellation that hosts the second brightest star in the northern sky, Vega. Look for it on summer nights.

The post Lyra the Harp contains Vega, a summer gem first appeared on EarthSky.

from EarthSky https://ift.tt/pGHIvCm

Pillars of Creation visualized in multiwavelength 3D

This image is a mosaic of visible-light and infrared-light views of the same frame from the Pillars of Creation visualization video. The three-dimensional model of the pillars created for the visualization sequence shows the Hubble Space Telescope version (visible light) and the Webb Space Telescope version (infrared light). Image via NASA/ Webb.

Webb Space Telescope originally published this article on June 26, 2024. Edits by EarthSky.

Pillars of Creation

NASA’s Hubble Space Telescope made the Pillars of Creation famous in 1995. It’s the heart of the Eagle Nebula and it captured imaginations worldwide with their arresting, ethereal beauty.

Now, NASA has released a new 3D visualization of these towering celestial structures using data from NASA’s Hubble and James Webb space telescopes. This is the most comprehensive and detailed multiwavelength movie yet of these star-birthing clouds.

The principal visualization scientist Frank Summers of the Space Telescope Science Institute (STScI) in Baltimore, led the movie development team for NASA’s Universe of Learning. Summers said:

By flying past and amongst the pillars, viewers experience their three-dimensional structure and see how they look different in the Hubble visible-light view versus the Webb infrared-light view. The contrast helps them understand why we have more than one space telescope to observe different aspects of the same object.

The four Pillars of Creation are made primarily of cool molecular hydrogen and dust. They are being eroded by the fierce winds and punishing ultraviolet light of nearby hot, young stars. Finger-like structures larger than the solar system protrude from the tops of the pillars. Within these fingers can be embedded, embryonic stars. The tallest pillar stretches across 3 light-years, 3/4 of the distance between our sun and the next nearest star.

Movie of the Pillars of Creation

The movie takes visitors into the three-dimensional structures of the pillars. Rather than an artistic interpretation, the video is based on observational data from a science paper led by Anna McLeod. McLeod is an associate professor at the University of Durham in the United Kingdom. McLeod also served as a scientific advisor on the movie project.

Production lead Greg Bacon of STScI said:

The Pillars of Creation were always on our minds to create in 3D. Webb data in combination with Hubble data allowed us to see the Pillars in more complete detail. Understanding the science and how to best represent it allowed our small, talented team to meet the challenge of visualizing this iconic structure.

The new visualization (video above) helps viewers experience how two of the world’s most powerful space telescopes work together to provide a more complex and holistic portrait of the pillars. Hubble sees objects that glow in visible light, at thousands of degrees. Webb’s infrared vision is sensitive to cooler objects. So it sees temperatures of just hundreds of degrees, and pierces through obscuring dust to see stars embedded in the pillars.

Using different wavelengths

According to Mark Clampin, Astrophysics Division director at NASA Headquarters in Washington:

When we combine observations from NASA’s space telescopes across different wavelengths of light, we broaden our understanding of the universe. The Pillars of Creation region continues to offer us new insights that hone our understanding of how stars form. Now, with this new visualization, everyone can experience this rich, captivating landscape in a new way.

STScI, with partners at Caltech/IPAChe, produced the 3D visualization for NASA, and the AstroViz Project of NASA’s Universe of Learning developed it. It is part of a longer, narrated video. It combines a direct connection to the science and scientists of NASA’s Astrophysics missions. Plus, it enables viewers to explore fundamental questions in science, experience how they do science and discover the universe for themselves.

Star formation

Several stages of star formation are in the visualization. First, as viewers approach the central pillar, they see at its top an embedded, infant protostar glimmering bright red in infrared light. Then, near the top of the left pillar is a diagonal jet of material ejected from a newborn star. Though the jet is evidence of star birth, viewers can’t see the star itself. Finally, at the end of one of the left pillar’s protruding “fingers” is a blazing, brand-new star.

Additionally, a bonus product from this visualization is a new 3D printable model of the Pillars of Creation. The base model of the four pillars used in the visualization has been adapted to the STL file format. So viewers can download the model file and print it out on 3D printers. Examining the structure of the pillars in this tactile and interactive way adds new perspectives and insights to the overall experience.

This photograph shows a 3D printed model of the famous Pillars of Creation in the Eagle Nebula. The 3D sculpted computer model used in the Pillars of Creation visualization. It is converted to STL file format and set atop a round base for use with 3D printers. Image via NASA / Webb.

Bottom line: NASA has released a new 3D visualization of the Pillars of Creation using data from NASA’s Hubble and James Webb space telescopes.

Via Webb Telescope

Read more: Pillars of Creation and more: Video and images

The post Pillars of Creation visualized in multiwavelength 3D first appeared on EarthSky.

from EarthSky https://ift.tt/Uzn8xal

This image is a mosaic of visible-light and infrared-light views of the same frame from the Pillars of Creation visualization video. The three-dimensional model of the pillars created for the visualization sequence shows the Hubble Space Telescope version (visible light) and the Webb Space Telescope version (infrared light). Image via NASA/ Webb.

Webb Space Telescope originally published this article on June 26, 2024. Edits by EarthSky.

Pillars of Creation

NASA’s Hubble Space Telescope made the Pillars of Creation famous in 1995. It’s the heart of the Eagle Nebula and it captured imaginations worldwide with their arresting, ethereal beauty.

Now, NASA has released a new 3D visualization of these towering celestial structures using data from NASA’s Hubble and James Webb space telescopes. This is the most comprehensive and detailed multiwavelength movie yet of these star-birthing clouds.

The principal visualization scientist Frank Summers of the Space Telescope Science Institute (STScI) in Baltimore, led the movie development team for NASA’s Universe of Learning. Summers said:

By flying past and amongst the pillars, viewers experience their three-dimensional structure and see how they look different in the Hubble visible-light view versus the Webb infrared-light view. The contrast helps them understand why we have more than one space telescope to observe different aspects of the same object.

The four Pillars of Creation are made primarily of cool molecular hydrogen and dust. They are being eroded by the fierce winds and punishing ultraviolet light of nearby hot, young stars. Finger-like structures larger than the solar system protrude from the tops of the pillars. Within these fingers can be embedded, embryonic stars. The tallest pillar stretches across 3 light-years, 3/4 of the distance between our sun and the next nearest star.

Movie of the Pillars of Creation

The movie takes visitors into the three-dimensional structures of the pillars. Rather than an artistic interpretation, the video is based on observational data from a science paper led by Anna McLeod. McLeod is an associate professor at the University of Durham in the United Kingdom. McLeod also served as a scientific advisor on the movie project.

Production lead Greg Bacon of STScI said:

The Pillars of Creation were always on our minds to create in 3D. Webb data in combination with Hubble data allowed us to see the Pillars in more complete detail. Understanding the science and how to best represent it allowed our small, talented team to meet the challenge of visualizing this iconic structure.

The new visualization (video above) helps viewers experience how two of the world’s most powerful space telescopes work together to provide a more complex and holistic portrait of the pillars. Hubble sees objects that glow in visible light, at thousands of degrees. Webb’s infrared vision is sensitive to cooler objects. So it sees temperatures of just hundreds of degrees, and pierces through obscuring dust to see stars embedded in the pillars.

Using different wavelengths

According to Mark Clampin, Astrophysics Division director at NASA Headquarters in Washington:

When we combine observations from NASA’s space telescopes across different wavelengths of light, we broaden our understanding of the universe. The Pillars of Creation region continues to offer us new insights that hone our understanding of how stars form. Now, with this new visualization, everyone can experience this rich, captivating landscape in a new way.

STScI, with partners at Caltech/IPAChe, produced the 3D visualization for NASA, and the AstroViz Project of NASA’s Universe of Learning developed it. It is part of a longer, narrated video. It combines a direct connection to the science and scientists of NASA’s Astrophysics missions. Plus, it enables viewers to explore fundamental questions in science, experience how they do science and discover the universe for themselves.

Star formation

Several stages of star formation are in the visualization. First, as viewers approach the central pillar, they see at its top an embedded, infant protostar glimmering bright red in infrared light. Then, near the top of the left pillar is a diagonal jet of material ejected from a newborn star. Though the jet is evidence of star birth, viewers can’t see the star itself. Finally, at the end of one of the left pillar’s protruding “fingers” is a blazing, brand-new star.

Additionally, a bonus product from this visualization is a new 3D printable model of the Pillars of Creation. The base model of the four pillars used in the visualization has been adapted to the STL file format. So viewers can download the model file and print it out on 3D printers. Examining the structure of the pillars in this tactile and interactive way adds new perspectives and insights to the overall experience.

This photograph shows a 3D printed model of the famous Pillars of Creation in the Eagle Nebula. The 3D sculpted computer model used in the Pillars of Creation visualization. It is converted to STL file format and set atop a round base for use with 3D printers. Image via NASA / Webb.

Bottom line: NASA has released a new 3D visualization of the Pillars of Creation using data from NASA’s Hubble and James Webb space telescopes.

Via Webb Telescope

Read more: Pillars of Creation and more: Video and images

The post Pillars of Creation visualized in multiwavelength 3D first appeared on EarthSky.

from EarthSky https://ift.tt/Uzn8xal

Cygnus the Swan flies along the Milky Way

Cygnus the Swan’s brightest star, Deneb, marks one of the corners of the Summer Triangle. And its bright double star, Albireo, is one of the finest in the heavens.

If you have a dark sky, it’s easy to see the edgewise view into our own galaxy – our Milky Way – spun across the heavens. As you look toward it, you’ll be gazing toward the constellation Cygnus the Swan, too. Its brightest star is called Deneb, the Swan’s Tail. And the constellation Cygnus contains one of the most beloved double stars in the sky, blue and gold Albireo.

Plus, the star Deneb marks one of the corners of the famous Summer Triangle, an asterism composed of three bright stars in three different constellations.

So there’s a lot going on in this part of the sky! And no wonder, because the Swan lets you peer into the depths of the Milky Way.

How to find Cygnus the Swan

Currently, you can find Cygnus high above the eastern horizon after sunset in summer. As the sky grows dark, the first of its stars that you’ll see is Deneb, the brightest in the constellation at magnitude 1.25. Deneb is the tail feather of the Swan, or the top of the lowercase “t” shape. In addition, Cygnus also has the nickname of the Northern Cross.

Later, as the night wears on, you’ll be able to trace out the body of the Swan and its bent wings. Then, you can find the double star, Albireo, which marks its head.

If you can find the large Summer Triangle shape, Deneb in Cygnus is the star that lies toward the northeast.

Then once you’ve found Cygnus, you just need to look along its length to find the hazy cloud behind it that is our galaxy, the Milky Way. The Milky Way, notably, runs along the same axis as the long line of the lowercase t or the body of the Swan.

The bright star Deneb is part of the famous Summer Triangle asterism. Its constellation, Cygnus the Swan, flies across the summer evening sky.

The Swan in skylore

The mythology of Cygnus tells the story of Zeus, who changed into the form of a swan to entice Queen Leda. From their union came the twins Castor and Pollux.

Now, we see them today as the bright stars of the constellation Gemini the Twins.

Stars of the Swan

Deneb, or Alpha Cygni, is the 19th brightest star in the sky. At magnitude 1.25, it’s a blue-white supergiant star lying about 1,500 light-years away, which is a long distance for a star that shines so brightly in our skies.

Albireo, the head of the Swan, is largely regarded as the most beautiful double star in the heavens. Indeed, you can easily divide Albireo into a larger yellow star and smaller blue star in a small telescope. The brighter star of Albireo (or Beta Cygni) is magnitude 3.1, and the dimmer is magnitude 5.8. The stars are approximately 380 light-years distant.

Omicron Cygni, or 30 and 31 Cygni, is a double star with orange and blue components that you can see with binoculars. These stars lie between Deneb and Delta Cygni, which is the western wing of the Swan. At magnitudes 4.8 and 3.8, 30 and 31 Cygni lie 610 and 1.350 light-years away, respectively.

Gliese 777 is a yellow subgiant star shining at 5.71 magnitude and located about 51 light-years distant. Two extrasolar planets have been confirmed in its system.

The constellation Cygnus with its stars, that form an asterism known as the Northern Cross. Image via IAU/ Sky & Telescope/ Wikimedia Commons.

Deep-sky objects in Cygnus

In addition, you can find an open cluster in Cygnus lying less than 2 degrees from Sadr, or Gamma Cygni, the third brightest star of the constellation, at magnitude 2.23, at the center of the cross or Swan. This open cluster is M29, at magnitude 7.1. With this in mind, try using binoculars to track it down.

Also, another Messier object in Cygnus is M39, an open cluster lying about 9 degrees northeast of Deneb. M39 is magnitude 5.5. In this case, you can try to spot with just your eyes alone.

Sadr and star clusters

Now, head back to Sadr. A 7.4-magnitude open cluster, NGC 6910, lies just a 1/2 degree north of the star. Scanning along the western boundary of Cygnus with binoculars or a telescope reveals other clusters, including the magnitude 7.3 Foxhead Cluster (NGC 6819) and the 6.8-magnitude Hole-in-a-Cluster (NGC 6811).

Also, on the western side of the constellation, 5 1/2 degrees north of Sadr, or Gamma Cygni, is the 8.8 magnitude Blinking Planetary, NGC 6826. To be sure, as you move your eyes across it, does it appear to blink?

View at EarthSky Community Photos. | Andy Dungan near Cotopaxi, Colorado, captured this image of the Sadr Star Region in Cygnus on May 25, 2023. Andy wrote: “Cygnus is full of fun stuff to shoot. I had no idea how large the area surrounding the central star of Cygnus (Sadr or Gamma Cygni) was. The large area around Sadr is identified as the Sadr Region or the Butterfly Nebula, IC 1318. This was shot at 300mm. At some point I am going to have to zoom in the Crescent Nebula, NGC 6888 (far right center), for a closer shot of that. I would also like to figure out how to bring the reds out more. What fun.” Thank you, Andy!

North America and Veil nebulae

The North America Nebula, or NGC 7000, lies a little over 3 degrees east of Deneb. When you look at it in photos, can you trace out the shape of the continent for which it’s named? You can glimpse this large nebula under dark skies with binoculars. In fact, it extends up to four moon-widths. As a matter of fact, depending on your vision and sky conditions, you might detect this large 4.4 magnitude nebula with your eyes alone.

You can also use binoculars to see the Veil Nebula, or NGC 6992. The Veil Nebula spans a big sweep of sky just south of Epsilon Cygni, the eastern star in the Swan’s wing. This entire region is the Cygnus Loop and consists of the remains of a star that exploded in a supernova 5,000 years ago.

View at EarthSky Community Photos. | Jeremy Likness in Monroe, Washington, captured this view of the North America Nebula in Cygnus on August 1, 2022. He wrote: “NGC 7000, the North America nebula, is bright, massive, and high in the sky this time of year. I framed it to show its namesake.” Thank you, Jeremy!

Cygnus is great to explore with binoculars

In addition to the objects mentioned above, you can explore Cygnus in binoculars. That’s because the Milky Way makes a rich background in this part of the sky. So you can find many more nebulae and clusters if you’re patient and sweep the area with binoculars or a telescope.

Bottom line: Cygnus the Swan is a constellation that lies atop the Milky Way. Also, its brightest star, Deneb, is part of the Summer Triangle.

Read more: Why 61 Cygni is nicknamed Flying Star

The post Cygnus the Swan flies along the Milky Way first appeared on EarthSky.

from EarthSky https://ift.tt/hovHs4m

Cygnus the Swan’s brightest star, Deneb, marks one of the corners of the Summer Triangle. And its bright double star, Albireo, is one of the finest in the heavens.

If you have a dark sky, it’s easy to see the edgewise view into our own galaxy – our Milky Way – spun across the heavens. As you look toward it, you’ll be gazing toward the constellation Cygnus the Swan, too. Its brightest star is called Deneb, the Swan’s Tail. And the constellation Cygnus contains one of the most beloved double stars in the sky, blue and gold Albireo.

Plus, the star Deneb marks one of the corners of the famous Summer Triangle, an asterism composed of three bright stars in three different constellations.

So there’s a lot going on in this part of the sky! And no wonder, because the Swan lets you peer into the depths of the Milky Way.

How to find Cygnus the Swan

Currently, you can find Cygnus high above the eastern horizon after sunset in summer. As the sky grows dark, the first of its stars that you’ll see is Deneb, the brightest in the constellation at magnitude 1.25. Deneb is the tail feather of the Swan, or the top of the lowercase “t” shape. In addition, Cygnus also has the nickname of the Northern Cross.

Later, as the night wears on, you’ll be able to trace out the body of the Swan and its bent wings. Then, you can find the double star, Albireo, which marks its head.

If you can find the large Summer Triangle shape, Deneb in Cygnus is the star that lies toward the northeast.

Then once you’ve found Cygnus, you just need to look along its length to find the hazy cloud behind it that is our galaxy, the Milky Way. The Milky Way, notably, runs along the same axis as the long line of the lowercase t or the body of the Swan.

The bright star Deneb is part of the famous Summer Triangle asterism. Its constellation, Cygnus the Swan, flies across the summer evening sky.

The Swan in skylore

The mythology of Cygnus tells the story of Zeus, who changed into the form of a swan to entice Queen Leda. From their union came the twins Castor and Pollux.

Now, we see them today as the bright stars of the constellation Gemini the Twins.

Stars of the Swan

Deneb, or Alpha Cygni, is the 19th brightest star in the sky. At magnitude 1.25, it’s a blue-white supergiant star lying about 1,500 light-years away, which is a long distance for a star that shines so brightly in our skies.

Albireo, the head of the Swan, is largely regarded as the most beautiful double star in the heavens. Indeed, you can easily divide Albireo into a larger yellow star and smaller blue star in a small telescope. The brighter star of Albireo (or Beta Cygni) is magnitude 3.1, and the dimmer is magnitude 5.8. The stars are approximately 380 light-years distant.

Omicron Cygni, or 30 and 31 Cygni, is a double star with orange and blue components that you can see with binoculars. These stars lie between Deneb and Delta Cygni, which is the western wing of the Swan. At magnitudes 4.8 and 3.8, 30 and 31 Cygni lie 610 and 1.350 light-years away, respectively.

Gliese 777 is a yellow subgiant star shining at 5.71 magnitude and located about 51 light-years distant. Two extrasolar planets have been confirmed in its system.

The constellation Cygnus with its stars, that form an asterism known as the Northern Cross. Image via IAU/ Sky & Telescope/ Wikimedia Commons.

Deep-sky objects in Cygnus

In addition, you can find an open cluster in Cygnus lying less than 2 degrees from Sadr, or Gamma Cygni, the third brightest star of the constellation, at magnitude 2.23, at the center of the cross or Swan. This open cluster is M29, at magnitude 7.1. With this in mind, try using binoculars to track it down.

Also, another Messier object in Cygnus is M39, an open cluster lying about 9 degrees northeast of Deneb. M39 is magnitude 5.5. In this case, you can try to spot with just your eyes alone.

Sadr and star clusters

Now, head back to Sadr. A 7.4-magnitude open cluster, NGC 6910, lies just a 1/2 degree north of the star. Scanning along the western boundary of Cygnus with binoculars or a telescope reveals other clusters, including the magnitude 7.3 Foxhead Cluster (NGC 6819) and the 6.8-magnitude Hole-in-a-Cluster (NGC 6811).

Also, on the western side of the constellation, 5 1/2 degrees north of Sadr, or Gamma Cygni, is the 8.8 magnitude Blinking Planetary, NGC 6826. To be sure, as you move your eyes across it, does it appear to blink?

View at EarthSky Community Photos. | Andy Dungan near Cotopaxi, Colorado, captured this image of the Sadr Star Region in Cygnus on May 25, 2023. Andy wrote: “Cygnus is full of fun stuff to shoot. I had no idea how large the area surrounding the central star of Cygnus (Sadr or Gamma Cygni) was. The large area around Sadr is identified as the Sadr Region or the Butterfly Nebula, IC 1318. This was shot at 300mm. At some point I am going to have to zoom in the Crescent Nebula, NGC 6888 (far right center), for a closer shot of that. I would also like to figure out how to bring the reds out more. What fun.” Thank you, Andy!

North America and Veil nebulae

The North America Nebula, or NGC 7000, lies a little over 3 degrees east of Deneb. When you look at it in photos, can you trace out the shape of the continent for which it’s named? You can glimpse this large nebula under dark skies with binoculars. In fact, it extends up to four moon-widths. As a matter of fact, depending on your vision and sky conditions, you might detect this large 4.4 magnitude nebula with your eyes alone.

You can also use binoculars to see the Veil Nebula, or NGC 6992. The Veil Nebula spans a big sweep of sky just south of Epsilon Cygni, the eastern star in the Swan’s wing. This entire region is the Cygnus Loop and consists of the remains of a star that exploded in a supernova 5,000 years ago.

View at EarthSky Community Photos. | Jeremy Likness in Monroe, Washington, captured this view of the North America Nebula in Cygnus on August 1, 2022. He wrote: “NGC 7000, the North America nebula, is bright, massive, and high in the sky this time of year. I framed it to show its namesake.” Thank you, Jeremy!

Cygnus is great to explore with binoculars

In addition to the objects mentioned above, you can explore Cygnus in binoculars. That’s because the Milky Way makes a rich background in this part of the sky. So you can find many more nebulae and clusters if you’re patient and sweep the area with binoculars or a telescope.

Bottom line: Cygnus the Swan is a constellation that lies atop the Milky Way. Also, its brightest star, Deneb, is part of the Summer Triangle.

Read more: Why 61 Cygni is nicknamed Flying Star

The post Cygnus the Swan flies along the Milky Way first appeared on EarthSky.

from EarthSky https://ift.tt/hovHs4m

Star clusters found in the Cosmic Gems arc by Webb

Massive star clusters found in early universe

Young galaxies in the early universe underwent phases of significant bursts of star formation, generating substantial amounts of ionizing radiation, that is, a type of energy released by atoms that travels in the form of electromagnetic waves (gamma or X-rays) or particles (neutrons, beta or alpha). However, because of their cosmological distances, direct studies of their stellar content have proven challenging.

Using the James Webb Space Telescope, an international team of astronomers have now detected five young massive star clusters in the Cosmic Gems arc (SPT0615-JD1). It’s a strongly-lensed galaxy emitting light when the universe was roughly 460 million years old, looking back across 97% of cosmic time.

The Cosmic Gems arc was initially discovered in Hubble Space Telescope images obtained by the (Reionization Lensing Cluster Survey) RELICS program. It was found when imaging the lensing galaxy cluster SPT-CL J0615-5746.

The lead author of the study is Angela Adamo of Stockholm University and the Oskar Klein Centre in Sweden. Angela said:

These galaxies are thought to be a prime source of the intense radiation that reionized the early universe. What is special about the Cosmic Gems arc is that thanks to gravitational lensing we can actually resolve the galaxy down to parsec scales!

Astronomers used the James Webb Space Telescope to discover gravitationally bound star clusters when the universe was 460 million years old. This is the 1st discovery of star clusters in an infant galaxy less than 500 million years after the Big bang. Image via ESA/ Webb/ NASA/ CSA.

Webb can image distant and young stars

With Webb, the science team can now see where stars formed and how they are distributed. That’s similar to how the Hubble Space Telescope studies local galaxies. Webb’s view provides a unique opportunity to study star formation and the inner workings of infant galaxies at such an unprecedented distance.

Larry Bradley of the Space Telescope Science Institute and PI of the Webb observing program said:

Webb’s incredible sensitivity and angular resolution at near-infrared wavelengths, combined with gravitational lensing provided by the massive foreground galaxy cluster, enabled this discovery. No other telescope could have made this discovery.

According to Adamo:

The surprise and astonishment was incredible when we opened the Webb images for the first time. We saw a little chain of bright dots, mirrored from one side to the other — these cosmic gems are star clusters! Without Webb we would not have known we were looking at star clusters in such a young galaxy!

The Cosmic Gems arc offers clues to early star formation

In our Milky Way we see ancient globular clusters of stars, which are bound by gravity and have survived for billions of years. These are old relics of intense star formation in the early universe. However, it’s not well understood where and when these clusters formed.

The detection of massive young star clusters in the Cosmic Gems arc provides us with an excellent view of the early stages of a process that may go on to form globular clusters. The newly detected clusters in the arc are massive, dense and located in a very small region of their galaxy. And they also contribute the majority of the ultraviolet light coming from their host galaxy. The clusters are significantly denser than nearby star clusters. This discovery will help scientists to better understand how infant galaxies formed their stars. Plus, it can help astronomers see where globular clusters formed.

The team notes that this discovery connects a variety of scientific fields. Adamo explained:

These results provide direct evidence that indicates proto-globular clusters formed in faint galaxies during the reionization era, which contributes to our understanding of how these galaxies have succeeded in reionizing the universe. This discovery also places important constraints on the formation of globular clusters and their initial properties. For instance, the high stellar densities found in the clusters provide us with the first indication of the processes taking place in their interiors, giving new insights into the possible formation of very massive stars and black hole seeds, which are both important for galaxy evolution.

Future studies

In the future, the team hopes to build a sample of galaxies for which similar resolutions can be achieved. Eros Vanzella from the INAF Astrophysics and Space Science Observatory of Bologna (OAS) said:

I am confident there are other systems like this waiting to be uncovered in the early universe, enabling us to further our understanding of early galaxies.

In the meantime, the team is preparing for further observations and spectroscopy with Webb.

Bradley added:

We plan to study this galaxy with Webb’s NIRSpec and MIRI instruments in Cycle 3. The NIRSpec observations will allow us to confirm the redshift of the galaxy and to study the ultraviolet emission of the star clusters, which will be used to study their physical properties in more detail. The MIRI observations will allow us to study the properties of ionized gas. The spectroscopic observations will also allow us to spatially map the star formation rate.

Bottom line: The Webb Space Telescope has discovered massive young star clusters in the Cosmic Gems arc. This can give astronomers insight on how galaxies and globular clusters formed.

Source: Bound star clusters observed in a lensed galaxy 460 Myr after the Big Bang

Via NASA

The post Star clusters found in the Cosmic Gems arc by Webb first appeared on EarthSky.

from EarthSky https://ift.tt/EJl0dxc

Massive star clusters found in early universe

Young galaxies in the early universe underwent phases of significant bursts of star formation, generating substantial amounts of ionizing radiation, that is, a type of energy released by atoms that travels in the form of electromagnetic waves (gamma or X-rays) or particles (neutrons, beta or alpha). However, because of their cosmological distances, direct studies of their stellar content have proven challenging.

Using the James Webb Space Telescope, an international team of astronomers have now detected five young massive star clusters in the Cosmic Gems arc (SPT0615-JD1). It’s a strongly-lensed galaxy emitting light when the universe was roughly 460 million years old, looking back across 97% of cosmic time.

The Cosmic Gems arc was initially discovered in Hubble Space Telescope images obtained by the (Reionization Lensing Cluster Survey) RELICS program. It was found when imaging the lensing galaxy cluster SPT-CL J0615-5746.

The lead author of the study is Angela Adamo of Stockholm University and the Oskar Klein Centre in Sweden. Angela said:

These galaxies are thought to be a prime source of the intense radiation that reionized the early universe. What is special about the Cosmic Gems arc is that thanks to gravitational lensing we can actually resolve the galaxy down to parsec scales!

Astronomers used the James Webb Space Telescope to discover gravitationally bound star clusters when the universe was 460 million years old. This is the 1st discovery of star clusters in an infant galaxy less than 500 million years after the Big bang. Image via ESA/ Webb/ NASA/ CSA.

Webb can image distant and young stars

With Webb, the science team can now see where stars formed and how they are distributed. That’s similar to how the Hubble Space Telescope studies local galaxies. Webb’s view provides a unique opportunity to study star formation and the inner workings of infant galaxies at such an unprecedented distance.

Larry Bradley of the Space Telescope Science Institute and PI of the Webb observing program said:

Webb’s incredible sensitivity and angular resolution at near-infrared wavelengths, combined with gravitational lensing provided by the massive foreground galaxy cluster, enabled this discovery. No other telescope could have made this discovery.

According to Adamo:

The surprise and astonishment was incredible when we opened the Webb images for the first time. We saw a little chain of bright dots, mirrored from one side to the other — these cosmic gems are star clusters! Without Webb we would not have known we were looking at star clusters in such a young galaxy!

The Cosmic Gems arc offers clues to early star formation

In our Milky Way we see ancient globular clusters of stars, which are bound by gravity and have survived for billions of years. These are old relics of intense star formation in the early universe. However, it’s not well understood where and when these clusters formed.

The detection of massive young star clusters in the Cosmic Gems arc provides us with an excellent view of the early stages of a process that may go on to form globular clusters. The newly detected clusters in the arc are massive, dense and located in a very small region of their galaxy. And they also contribute the majority of the ultraviolet light coming from their host galaxy. The clusters are significantly denser than nearby star clusters. This discovery will help scientists to better understand how infant galaxies formed their stars. Plus, it can help astronomers see where globular clusters formed.

The team notes that this discovery connects a variety of scientific fields. Adamo explained:

These results provide direct evidence that indicates proto-globular clusters formed in faint galaxies during the reionization era, which contributes to our understanding of how these galaxies have succeeded in reionizing the universe. This discovery also places important constraints on the formation of globular clusters and their initial properties. For instance, the high stellar densities found in the clusters provide us with the first indication of the processes taking place in their interiors, giving new insights into the possible formation of very massive stars and black hole seeds, which are both important for galaxy evolution.

Future studies

In the future, the team hopes to build a sample of galaxies for which similar resolutions can be achieved. Eros Vanzella from the INAF Astrophysics and Space Science Observatory of Bologna (OAS) said:

I am confident there are other systems like this waiting to be uncovered in the early universe, enabling us to further our understanding of early galaxies.

In the meantime, the team is preparing for further observations and spectroscopy with Webb.

Bradley added:

We plan to study this galaxy with Webb’s NIRSpec and MIRI instruments in Cycle 3. The NIRSpec observations will allow us to confirm the redshift of the galaxy and to study the ultraviolet emission of the star clusters, which will be used to study their physical properties in more detail. The MIRI observations will allow us to study the properties of ionized gas. The spectroscopic observations will also allow us to spatially map the star formation rate.

Bottom line: The Webb Space Telescope has discovered massive young star clusters in the Cosmic Gems arc. This can give astronomers insight on how galaxies and globular clusters formed.

Source: Bound star clusters observed in a lensed galaxy 460 Myr after the Big Bang

Via NASA

The post Star clusters found in the Cosmic Gems arc by Webb first appeared on EarthSky.

from EarthSky https://ift.tt/EJl0dxc

Draco the Dragon, and a former pole star

Johannes Hevelius drew the constellation Draco the Dragon in Uranographia, his celestial catalog, in 1690. He plotted the sky in reverse, as if seen from above, facing down towards the earth. Note the circle around the Dragon and the star where the Dragon’s Tail intersects the circle. That star is Thuban, a former pole star. Image via Wikimedia Commons.

Draco and its famous star Thuban

Tonight, if you have a dark sky, you’ll be able to pick out the constellation Draco the Dragon winding around our modern-day pole star, aka the North Star, which we call Polaris. The image at the top of this post shows Draco as depicted in an old star atlas by Johannes Hevelius in 1690. See the circle? That circle indicates the changing position of the north celestial pole over a cycle of 26,000 years.

The 26,000-year cycle is known as precession. It’s a slow, smooth wobbling that causes a change in the orientation of Earth’s axis over time. Precession causes Earth’s axis to trace out a circle among the stars. Thus, over time, Earth’s axis points to various stars, and the identity of our North Star changes.

Precession of the Earth's Rotation Axis and North Star. The Earth's rotation axis is not fixed in space. Like a rotating toy top, the direction of the rotation axis executes a slow precession with a period of 26,000 years. https://t.co/h7nS1BCuOl pic.twitter.com/SRVQGQDYP0

— Space Explorer Mike ?? (@MichaelGalanin) March 27, 2021

So our modern-day Polaris wasn’t always our north pole star. It was once an ordinary star in the northern sky, called Phoenice. And a star in Draco, called Thuban, was the pole star when the Egyptians built the pyramids some 5,000 years ago.

The 26,000-year precession cycle causes the north celestial pole to move counterclockwise relative to the background stars. Whichever star is closest to the north celestial pole is called the North Star. From Wikipedia.

Draco winds between the Big and Little Dippers

Luckily, the Big Dipper can help guide you to Draco and its star Thuban. Just remember … the entire Dragon requires a dark sky to see. You’ll find the Big Dipper high in the north on June evenings. The two outer stars in the Dipper’s bowl point to our modern-day Polaris, the North Star, which marks the end of the Little Dipper’s handle.

The Little Dipper is relatively faint. If you can find both Dippers, then your sky is probably pretty dark. And you’ll need that dark sky to see Draco. You’ll have to let your eyes and imagination drift a bit to see the entire winding shape of the Dragon in the northern heavens.

See how the tail of Draco winds between the Big and Little Dippers on the chart below?

If you can find the Big and Little Dippers, you can find the constellation Draco the Dragon. The star Thuban lies between the Dippers.

And here’s Draco the Dragon and the Little Dipper. The four stars that make up Draco’s head, are the usually the easiest pattern to pick out.

Eltanin and Rastaban mark the head of Draco the Dragon. You’ll find these stars in the northern sky.

Thuban is easy to find

Also – if you can find both Dippers, and if your sky is relatively dark – you can easily pick out Thuban. The star is easy to find by looking between the Dippers. It is 1.6 magnitudes fainter than Polaris, which means Polaris is four times brighter. Thuban is famous for having served as a pole star around 3000 BCE. This date coincides with the beginning of the building of the pyramids in Egypt. It’s said that the descending passage of the Great Pyramid of Khufu at Gizeh was built to point directly at Thuban. So our ancestors knew and celebrated this star. Now the descending path points towards Polaris, the current North Star.

Thuban reigned as the pole star for more than a thousand years. It was closest to the pole in the year 2830 BCE, at a distance of only 10 arcminutes, or 1/6 of a degree. This even “out-polar-ized” Polaris, which will get no closer than 27 arcminutes to true north next century.

Thuban as North Star

For 200 years, Thuban was within 1 degree of true north. But as the centuries passed, so did the stars targeted to be our North Star. Thuban will get its turn again in the year 20,346 CE. Don’t wait up for it!

Through a telescope, Thuban is a blue-white star, magnitude 3.67. It is located 303 light-years away, is about five times larger than our sun, and shines 240 times brighter than our sun. It has a companion, but it is too close to the primary star to observe.

And Polaris? Its reign began in 1547 when Gemma Frisius first referred to it as “that star which is called polar.” In July 2016, the International Astronomical Union‘s (IAU) Working Group on Star Names officially declared the star to be named Polaris.

Then in a few thousand years. Polaris will no longer be the North Star. Perhaps then the IAU will assemble their Working Group of Star Names and change the name back to Phoenice. (P.S. Dear Pluto, there is hope!)

Read more about Thuban, a former pole star

Bottom line: Let your eyes and imagination drift a bit to see the entire winding shape of Draco the Dragon in the northern sky. If you do spot it, be sure to pick out Thuban, a former pole star.

Read more: How to find the Big Dipper

The post Draco the Dragon, and a former pole star first appeared on EarthSky.

from EarthSky https://ift.tt/Z4N0FAm

Johannes Hevelius drew the constellation Draco the Dragon in Uranographia, his celestial catalog, in 1690. He plotted the sky in reverse, as if seen from above, facing down towards the earth. Note the circle around the Dragon and the star where the Dragon’s Tail intersects the circle. That star is Thuban, a former pole star. Image via Wikimedia Commons.

Draco and its famous star Thuban

Tonight, if you have a dark sky, you’ll be able to pick out the constellation Draco the Dragon winding around our modern-day pole star, aka the North Star, which we call Polaris. The image at the top of this post shows Draco as depicted in an old star atlas by Johannes Hevelius in 1690. See the circle? That circle indicates the changing position of the north celestial pole over a cycle of 26,000 years.

The 26,000-year cycle is known as precession. It’s a slow, smooth wobbling that causes a change in the orientation of Earth’s axis over time. Precession causes Earth’s axis to trace out a circle among the stars. Thus, over time, Earth’s axis points to various stars, and the identity of our North Star changes.

Precession of the Earth's Rotation Axis and North Star. The Earth's rotation axis is not fixed in space. Like a rotating toy top, the direction of the rotation axis executes a slow precession with a period of 26,000 years. https://t.co/h7nS1BCuOl pic.twitter.com/SRVQGQDYP0

— Space Explorer Mike ?? (@MichaelGalanin) March 27, 2021

So our modern-day Polaris wasn’t always our north pole star. It was once an ordinary star in the northern sky, called Phoenice. And a star in Draco, called Thuban, was the pole star when the Egyptians built the pyramids some 5,000 years ago.

The 26,000-year precession cycle causes the north celestial pole to move counterclockwise relative to the background stars. Whichever star is closest to the north celestial pole is called the North Star. From Wikipedia.

Draco winds between the Big and Little Dippers

Luckily, the Big Dipper can help guide you to Draco and its star Thuban. Just remember … the entire Dragon requires a dark sky to see. You’ll find the Big Dipper high in the north on June evenings. The two outer stars in the Dipper’s bowl point to our modern-day Polaris, the North Star, which marks the end of the Little Dipper’s handle.

The Little Dipper is relatively faint. If you can find both Dippers, then your sky is probably pretty dark. And you’ll need that dark sky to see Draco. You’ll have to let your eyes and imagination drift a bit to see the entire winding shape of the Dragon in the northern heavens.

See how the tail of Draco winds between the Big and Little Dippers on the chart below?

If you can find the Big and Little Dippers, you can find the constellation Draco the Dragon. The star Thuban lies between the Dippers.

And here’s Draco the Dragon and the Little Dipper. The four stars that make up Draco’s head, are the usually the easiest pattern to pick out.

Eltanin and Rastaban mark the head of Draco the Dragon. You’ll find these stars in the northern sky.

Thuban is easy to find

Also – if you can find both Dippers, and if your sky is relatively dark – you can easily pick out Thuban. The star is easy to find by looking between the Dippers. It is 1.6 magnitudes fainter than Polaris, which means Polaris is four times brighter. Thuban is famous for having served as a pole star around 3000 BCE. This date coincides with the beginning of the building of the pyramids in Egypt. It’s said that the descending passage of the Great Pyramid of Khufu at Gizeh was built to point directly at Thuban. So our ancestors knew and celebrated this star. Now the descending path points towards Polaris, the current North Star.

Thuban reigned as the pole star for more than a thousand years. It was closest to the pole in the year 2830 BCE, at a distance of only 10 arcminutes, or 1/6 of a degree. This even “out-polar-ized” Polaris, which will get no closer than 27 arcminutes to true north next century.

Thuban as North Star

For 200 years, Thuban was within 1 degree of true north. But as the centuries passed, so did the stars targeted to be our North Star. Thuban will get its turn again in the year 20,346 CE. Don’t wait up for it!

Through a telescope, Thuban is a blue-white star, magnitude 3.67. It is located 303 light-years away, is about five times larger than our sun, and shines 240 times brighter than our sun. It has a companion, but it is too close to the primary star to observe.

And Polaris? Its reign began in 1547 when Gemma Frisius first referred to it as “that star which is called polar.” In July 2016, the International Astronomical Union‘s (IAU) Working Group on Star Names officially declared the star to be named Polaris.

Then in a few thousand years. Polaris will no longer be the North Star. Perhaps then the IAU will assemble their Working Group of Star Names and change the name back to Phoenice. (P.S. Dear Pluto, there is hope!)

Read more about Thuban, a former pole star

Bottom line: Let your eyes and imagination drift a bit to see the entire winding shape of Draco the Dragon in the northern sky. If you do spot it, be sure to pick out Thuban, a former pole star.

Read more: How to find the Big Dipper

The post Draco the Dragon, and a former pole star first appeared on EarthSky.

from EarthSky https://ift.tt/Z4N0FAm