All you need to know: Draconids in 2019

Composite image of Draconids seen near Tucson, Arizona, in 2013, by our friend Sean Parker Photography.

October’s Draconid meteor shower – sometimes called the Giacobinids – is gearing up. In 2019, though, a bright waxing gibbous moon will intrude the show on the Draconids expected peak night on October 8. The Draconid shower is usually a sleeper, rarely offering any more than five meteors per hour. But watch out if the Dragon awakes! The Draconid meteor shower produced awesome meteor displays in 1933 and 1946, with thousands of meteors per hour seen in those years. European observers saw over 600 meteors per hour in 2011.

The Draconid shower is active between October 6 and 10. As noted above, the best evening to watch is likely October 8; try the evenings of October 7 and 9 also. Notice the word evening. This is one shower you don’t have to stay up late to see. Start watching first thing at nightfall. Be sure to watch under a dark, open, country sky.

Draconid meteor seen from Italy in 2011, flying near the bright star Vega in the constellation Lyra. The stars Eltanin and Rastaban in Draco – near the radiant of the Draconid meteor shower – shine close to Vega. Image via Vittorio Poli.

How many Draconids will you see? In general, the Draconids aren’t a rich shower, unless their parent comet is nearby. They typically produce only about five meteors per hour.

This annual meteor shower happens when Earth in its orbit crosses the orbital path of Comet 21P/Giacobini-Zinner. Debris left behind by this comet collides with the Earth’s upper atmosphere, to burn up as Draconid meteors. This comet has an orbital period of about 6.6 years. It’s about six times more distant at its farthest point from the sun than at its nearest point. At aphelion – its most distant point – it’s farther out than the planet Jupiter. At perihelion – its closest point to the sun – it’s about the Earth’s distance from the sun.

On rare occasions – when the peak of the shower coincides with the comet’s perihelion – this shower has been known to rain down hundreds or even thousands of meteors in an hour.

The last perihelion of the comet was September 10, 2018. On that same night, Comet 21P/Giacobini-Zinner came closer to Earth than it had in 72 years. Consequently, the Draconids had an outburst in 2018. We posted best pics of the comet as it swept safely past.

Because this comet has an orbital period of nearly 7 years, the next perihelion won’t come until 2025. So we’re not expecting any outburst this year, in 2019. But, then, no one really knows for sure.

For people who enjoy meteor showers, that’s part of the fun! As a wise person once said, meteor showers are like fishing. You go, and sometimes you catch something.

View larger. | Greg Hogan in Kathleen, Georgia, U.S., wrote on September 10, 2018: “I was able to grab a shot of Comet 21P/Giacobini-Zinner (top left), alongside Messier 37 (star cluster, bottom right). The comet looked like a little fuzzy spot through the ‘scope.” Thanks, Greg! See more photos of Comet 21P/Giacobini-Zinner in 2018.

Where is the radiant point of the Draconid shower? The Draconids are best in the evening, instead of before dawn, because the winged Dragon, the shower’s radiant point, flies highest in the sky at nightfall.

As night passes – no matter where you are on Earth – the radiant point sinks lower in your sky.

The Draconid meteors, when traced backward, radiate from the head of Draco the Dragon, near the stars Eltanin and Rastaban.

You don’t have to locate Draco the Dragon to watch the Draconids. These meteors fly every which way through the starry sky. But finding Draco is fun, and relatively easy.

More about the Draconid meteor shower radiant point here.

Draconids radiate from near the Dragon’s Eyes: the stars Eltanin and Rastaban. Familiar with the Summer Triangle? Draw an imaginary line from Altair through Vega and it will point to them.

Here’s a more detailed view of the radiant point of the Draconid meteor shower. It’s highest in the north at nightfall in early October.

The Draconids have a rich history. Most meteors in annual showers are named for the constellation from which they appear to radiate, in this case Draco the Dragon.

Draco’s meteors, however, defy convention by sometimes also being called the Giacobinids, to honor the role this comet played in the history of astronomers’ understanding of what meteors actually are.

Michel Giacobini discovered this comet on December 20, 1900, so the comet received his name. Another sighting in 1913 added Zinner to the comet’s name, which thus became 21P/Giacobini-Zinner. Astronomers in the early 20th century thought that meteors and comets were related, so of course they tried to link various comets to the spectacular showers of meteors that sometimes rain down in Earth’s sky.

Comet 21P/Giacobini-Zinner was a particularly tempting object about which to make predictions. Remember, it returns every 6.6 years, and its closest point to the sun is about the same as Earth’s distance.

What’s more, Comet Giacobini-Zinner did not disappoint the astronomers.

The Draconid meteor shower produced awesome meteor displays in 1933 and 1946, with thousands of meteors per hour seen in those years.

In October 2011, people around the globe saw an elevated number of Draconid meteors, despite a bright moon that night. European observers saw over 600 meteors per hour in 2011.

The relationship between 21P/Giacobini-Zinner and its meteors – so studied and discussed among professional astronomers in the early 20th century – probably explains why the Draconid meteor shower sometimes goes by the name Giacobinids.

For a taste of history related to this shower, go to the Astronomy Abstract Service from the Smithsonian and NASA and find a 1934 article called The Meteors from Giacobini’s Comet by C.C. Wylie. It’s an account of the famed meteor storm of 1933.

The constellation Draco from Uranographia by Johannes Hevelius, 1690, via Pinterest.

Can you see the Draconids from the Southern Hemisphere? It’s possible. But if you’re so far south that the radiant point in the constellation Draco doesn’t rise above your horizon, or rises only briefly, you won’t catch many.

As seen from the Southern Hemisphere, you would have to be rather close to the equator in order to see Draco’s stars. Suppose you live in northern Australia – say Darwin, in northern Australia – which is at 12 degrees south latitude. If so, you’d be able to see the stars Rastaban and Eltanin very close to your north-northwest horizon at nightfall in early October (given an unobstructed northern horizon). These stars would set at fairly early evening, and you wouldn’t see the head of Draco again until nightfall the following evening.

Why early evening? It’s because, no matter where you live worldwide, the head of Draco reaches upper transit (highest point in your sky) at around 5 p.m. local time in early October.

Thus from latitudes in the Southern Hemisphere – even those as far north as northern Australia – you would have a very narrow window for seeing meteors. If you’re in the Southern Hemisphere, and you’re really wanting to see a Draconid, try looking as soon as it gets really dark on October 7 and 8, and don’t expect much.

Photo composite – 5 Draconid meteors in less than an hour – on October 7, 2017, from Stephanie Longo at Pike National Forest in Tarryall, Colorado.

Bottom line: In 2019, the Draconid meteor shower – also called the Giacobinids – will probably produce the most meteors on the evening of October 8. Try the evenings of October 7 and 9 also. Don’t wait until after midnight. Watch as soon as it gets dark outside. Find a dark country sky and as much open sky as possible.

EarthSky meteor shower guide for 2019

Photographer and educator Noel Chenier posted tips for photographing Draconid meteors in this 2013 blog post.

from EarthSky https://ift.tt/2mOGQCC

Composite image of Draconids seen near Tucson, Arizona, in 2013, by our friend Sean Parker Photography.

October’s Draconid meteor shower – sometimes called the Giacobinids – is gearing up. In 2019, though, a bright waxing gibbous moon will intrude the show on the Draconids expected peak night on October 8. The Draconid shower is usually a sleeper, rarely offering any more than five meteors per hour. But watch out if the Dragon awakes! The Draconid meteor shower produced awesome meteor displays in 1933 and 1946, with thousands of meteors per hour seen in those years. European observers saw over 600 meteors per hour in 2011.

The Draconid shower is active between October 6 and 10. As noted above, the best evening to watch is likely October 8; try the evenings of October 7 and 9 also. Notice the word evening. This is one shower you don’t have to stay up late to see. Start watching first thing at nightfall. Be sure to watch under a dark, open, country sky.

Draconid meteor seen from Italy in 2011, flying near the bright star Vega in the constellation Lyra. The stars Eltanin and Rastaban in Draco – near the radiant of the Draconid meteor shower – shine close to Vega. Image via Vittorio Poli.

How many Draconids will you see? In general, the Draconids aren’t a rich shower, unless their parent comet is nearby. They typically produce only about five meteors per hour.

This annual meteor shower happens when Earth in its orbit crosses the orbital path of Comet 21P/Giacobini-Zinner. Debris left behind by this comet collides with the Earth’s upper atmosphere, to burn up as Draconid meteors. This comet has an orbital period of about 6.6 years. It’s about six times more distant at its farthest point from the sun than at its nearest point. At aphelion – its most distant point – it’s farther out than the planet Jupiter. At perihelion – its closest point to the sun – it’s about the Earth’s distance from the sun.

On rare occasions – when the peak of the shower coincides with the comet’s perihelion – this shower has been known to rain down hundreds or even thousands of meteors in an hour.

The last perihelion of the comet was September 10, 2018. On that same night, Comet 21P/Giacobini-Zinner came closer to Earth than it had in 72 years. Consequently, the Draconids had an outburst in 2018. We posted best pics of the comet as it swept safely past.

Because this comet has an orbital period of nearly 7 years, the next perihelion won’t come until 2025. So we’re not expecting any outburst this year, in 2019. But, then, no one really knows for sure.

For people who enjoy meteor showers, that’s part of the fun! As a wise person once said, meteor showers are like fishing. You go, and sometimes you catch something.

View larger. | Greg Hogan in Kathleen, Georgia, U.S., wrote on September 10, 2018: “I was able to grab a shot of Comet 21P/Giacobini-Zinner (top left), alongside Messier 37 (star cluster, bottom right). The comet looked like a little fuzzy spot through the ‘scope.” Thanks, Greg! See more photos of Comet 21P/Giacobini-Zinner in 2018.

Where is the radiant point of the Draconid shower? The Draconids are best in the evening, instead of before dawn, because the winged Dragon, the shower’s radiant point, flies highest in the sky at nightfall.

As night passes – no matter where you are on Earth – the radiant point sinks lower in your sky.

The Draconid meteors, when traced backward, radiate from the head of Draco the Dragon, near the stars Eltanin and Rastaban.

You don’t have to locate Draco the Dragon to watch the Draconids. These meteors fly every which way through the starry sky. But finding Draco is fun, and relatively easy.

More about the Draconid meteor shower radiant point here.

Draconids radiate from near the Dragon’s Eyes: the stars Eltanin and Rastaban. Familiar with the Summer Triangle? Draw an imaginary line from Altair through Vega and it will point to them.

Here’s a more detailed view of the radiant point of the Draconid meteor shower. It’s highest in the north at nightfall in early October.

The Draconids have a rich history. Most meteors in annual showers are named for the constellation from which they appear to radiate, in this case Draco the Dragon.

Draco’s meteors, however, defy convention by sometimes also being called the Giacobinids, to honor the role this comet played in the history of astronomers’ understanding of what meteors actually are.

Michel Giacobini discovered this comet on December 20, 1900, so the comet received his name. Another sighting in 1913 added Zinner to the comet’s name, which thus became 21P/Giacobini-Zinner. Astronomers in the early 20th century thought that meteors and comets were related, so of course they tried to link various comets to the spectacular showers of meteors that sometimes rain down in Earth’s sky.

Comet 21P/Giacobini-Zinner was a particularly tempting object about which to make predictions. Remember, it returns every 6.6 years, and its closest point to the sun is about the same as Earth’s distance.

What’s more, Comet Giacobini-Zinner did not disappoint the astronomers.

The Draconid meteor shower produced awesome meteor displays in 1933 and 1946, with thousands of meteors per hour seen in those years.

In October 2011, people around the globe saw an elevated number of Draconid meteors, despite a bright moon that night. European observers saw over 600 meteors per hour in 2011.

The relationship between 21P/Giacobini-Zinner and its meteors – so studied and discussed among professional astronomers in the early 20th century – probably explains why the Draconid meteor shower sometimes goes by the name Giacobinids.

For a taste of history related to this shower, go to the Astronomy Abstract Service from the Smithsonian and NASA and find a 1934 article called The Meteors from Giacobini’s Comet by C.C. Wylie. It’s an account of the famed meteor storm of 1933.

The constellation Draco from Uranographia by Johannes Hevelius, 1690, via Pinterest.

Can you see the Draconids from the Southern Hemisphere? It’s possible. But if you’re so far south that the radiant point in the constellation Draco doesn’t rise above your horizon, or rises only briefly, you won’t catch many.

As seen from the Southern Hemisphere, you would have to be rather close to the equator in order to see Draco’s stars. Suppose you live in northern Australia – say Darwin, in northern Australia – which is at 12 degrees south latitude. If so, you’d be able to see the stars Rastaban and Eltanin very close to your north-northwest horizon at nightfall in early October (given an unobstructed northern horizon). These stars would set at fairly early evening, and you wouldn’t see the head of Draco again until nightfall the following evening.

Why early evening? It’s because, no matter where you live worldwide, the head of Draco reaches upper transit (highest point in your sky) at around 5 p.m. local time in early October.

Thus from latitudes in the Southern Hemisphere – even those as far north as northern Australia – you would have a very narrow window for seeing meteors. If you’re in the Southern Hemisphere, and you’re really wanting to see a Draconid, try looking as soon as it gets really dark on October 7 and 8, and don’t expect much.

Photo composite – 5 Draconid meteors in less than an hour – on October 7, 2017, from Stephanie Longo at Pike National Forest in Tarryall, Colorado.

Bottom line: In 2019, the Draconid meteor shower – also called the Giacobinids – will probably produce the most meteors on the evening of October 8. Try the evenings of October 7 and 9 also. Don’t wait until after midnight. Watch as soon as it gets dark outside. Find a dark country sky and as much open sky as possible.

EarthSky meteor shower guide for 2019

Photographer and educator Noel Chenier posted tips for photographing Draconid meteors in this 2013 blog post.

from EarthSky https://ift.tt/2mOGQCC

These giant croc-like carnivores terrorized Triassic dinosaurs

Artist’s reconstruction of two rauisuchians over desiccated corpse of mammal-relative in the Triassic of southern Africa. In the background, dinosaurs and mammal-like reptiles form other parts of the ecosystem. Image via Viktor Radermachar.

Scientists have identified fossil remains from museum collections as belonging to giant, crocodile-like animals that preyed on early dinosaurs and mammal relatives 210 million years ago. These predators, known as rauisuchians, lived in southern Africa during the Triassic period, which spans 252 to 201 million years ago.

Rauisuchians are closely related to today’s crocodiles. They had massive jaws, walked on all fours, and were covered in crocodile-like armored scales. They had a diversity of body shapes and sizes, but the specimens described in this research include some of the largest carnivorous members of the group, possibly up to 33 feet (10 meters) long – about the length of a school bus, with huge skulls full of serrated, curved teeth.

According to the study, published online in the Journal of African Earth Sciences on August 27, 2019, the rauisuchians were some of the latest-surviving members of their group, and that when they were alive, they were thriving close to the Antarctic Circle – the theoretical limit for their physiology.

Rauisuchia is an order of reptiles that lived during the Triassic period. This group is the sister group to the group that gave rise to the modern-day crocodiles, alligators, and caimans. This group includes the largest non-dinosaurian land carnivore ever and some were so large that they could go head to head with T. rex. Image via Dinopedia

The researchers studied fossilized teeth, pieces of jaws, hind limbs and body armour, found in South Africa’s Eliot Formation, a geological formation of reddish-colored rocks well-known for its dinosaur fossils. The fossils were from collections based at the University of the Witwatersrand, the Iziko South African Museum and the National Museum in Bloemfontein, South Africa.

Location of the Eliot Formation in South Africa.

Rick Tolchard, of University of the Witwatersrand, is the study lead author. He said in a statement:

In the Triassic period, rauisuchians were widespread and their fossils are known from all continents except Antarctica. They went extinct about 200 million years ago, paving the way for dinosaurs to become the dominant large land animals.

An example of rauisuchian teeth. Image via Daily Maverick.

Tolchard said rauisuchians preyed on early herbivore dinosaurs and their mammal relatives living at the time. He said:

These ancient fossils provide us with evidence of how at least two predator species hunted these vegetarian dinosaurs 210 million-years-ago. It is amazing to follow the clues left behind in fossilized teeth, jaws, limbs and other fossils to help us tell the ancient story of life in southern Africa.

Source: ‘Rauisuchian’ material from the lower Elliot Formation of South Africa and Lesotho: Implications for Late Triassic biogeography and biostratigraphy

Via University of the Witwatersrand, Johannesburg

Bottom line: Fossil remains found in South Africa have been identified as belonging to an extinct relative of crocodiles.

from EarthSky https://ift.tt/2mSxaap

Artist’s reconstruction of two rauisuchians over desiccated corpse of mammal-relative in the Triassic of southern Africa. In the background, dinosaurs and mammal-like reptiles form other parts of the ecosystem. Image via Viktor Radermachar.

Scientists have identified fossil remains from museum collections as belonging to giant, crocodile-like animals that preyed on early dinosaurs and mammal relatives 210 million years ago. These predators, known as rauisuchians, lived in southern Africa during the Triassic period, which spans 252 to 201 million years ago.

Rauisuchians are closely related to today’s crocodiles. They had massive jaws, walked on all fours, and were covered in crocodile-like armored scales. They had a diversity of body shapes and sizes, but the specimens described in this research include some of the largest carnivorous members of the group, possibly up to 33 feet (10 meters) long – about the length of a school bus, with huge skulls full of serrated, curved teeth.

According to the study, published online in the Journal of African Earth Sciences on August 27, 2019, the rauisuchians were some of the latest-surviving members of their group, and that when they were alive, they were thriving close to the Antarctic Circle – the theoretical limit for their physiology.

Rauisuchia is an order of reptiles that lived during the Triassic period. This group is the sister group to the group that gave rise to the modern-day crocodiles, alligators, and caimans. This group includes the largest non-dinosaurian land carnivore ever and some were so large that they could go head to head with T. rex. Image via Dinopedia

The researchers studied fossilized teeth, pieces of jaws, hind limbs and body armour, found in South Africa’s Eliot Formation, a geological formation of reddish-colored rocks well-known for its dinosaur fossils. The fossils were from collections based at the University of the Witwatersrand, the Iziko South African Museum and the National Museum in Bloemfontein, South Africa.

Location of the Eliot Formation in South Africa.

Rick Tolchard, of University of the Witwatersrand, is the study lead author. He said in a statement:

In the Triassic period, rauisuchians were widespread and their fossils are known from all continents except Antarctica. They went extinct about 200 million years ago, paving the way for dinosaurs to become the dominant large land animals.

An example of rauisuchian teeth. Image via Daily Maverick.

Tolchard said rauisuchians preyed on early herbivore dinosaurs and their mammal relatives living at the time. He said:

These ancient fossils provide us with evidence of how at least two predator species hunted these vegetarian dinosaurs 210 million-years-ago. It is amazing to follow the clues left behind in fossilized teeth, jaws, limbs and other fossils to help us tell the ancient story of life in southern Africa.

Source: ‘Rauisuchian’ material from the lower Elliot Formation of South Africa and Lesotho: Implications for Late Triassic biogeography and biostratigraphy

Via University of the Witwatersrand, Johannesburg

Bottom line: Fossil remains found in South Africa have been identified as belonging to an extinct relative of crocodiles.

from EarthSky https://ift.tt/2mSxaap

International Observe the Moon Night is October 5

View larger. | Click here to join the Virtual Telescope Project of Rome, for online moon viewing on International Observe the Moon night.

International Observe the Moon Night (InOMN 2019) is back, scheduled for October 5, 2019. It’ll be a special one this year, coming, as it does, in the year of the 50th anniversary of Apollo 11’s historic landing on the moon on July 20, 1969. There are many ways to celebrate the event, which we talk about below. In addition, the Virtual Telescope Project in Rome invites you to join InOMN 2019 online, live, from the comfort of your home, allowing you to enjoy the moon above Rome’s stunning skyline.

The online, free session is scheduled for October 5 2019, starting at 17:00 UTC; translate UTC to your time. To join the International Observe the Moon Night online, via the Virtual Telescope Project, you just need to enter at the date and time above the webTV page here.

NASA described this event on InOMN webpage:

International Observe the Moon Night is a worldwide celebration of lunar science and exploration, celestial observation, and our cultural and personal connections to the moon. One day each year, everyone on Earth is invited to observe, learn about, and celebrate the moon together.

This event always occurs in September or October, at a time when the moon is around first quarter – a great phase for evening observing. Furthermore, the best lunar observing is typically along the moon’s terminator (the line between night and day) where shadows are the longest, rather than at full moon.

You can participate by attending or hosting an International Observe the Moon Night event, or by registering as a lunar observer. Connect with fellow lunar enthusiasts around the world through NASA’s Facebook page, #ObserveTheMoon on your preferred social media platform, and the International Observe the Moon Night Flickr group.

To sum up, here are some next steps if you want to join International Observe the Moon Night 2019:

InOMN 2019: Join the Virtual Telescope Project to view the moon online, above the skyline of Rome

InOMN 2019: Attend an event in your location

InOMN 2019: Host an event

InOMN 2019: Register with NASA as a lunar observer

View NASA’s InOMN 2019 Facebook page

View NASA’s InOMN 2019 Flickr group

Bottom line: International Observe the Moon Night is October 5, 2019. Here are some ways to join in.

Join the Virtual Telescope Project to view the moon online, on International Observe the Moon night

from EarthSky https://ift.tt/2nzI8lC

View larger. | Click here to join the Virtual Telescope Project of Rome, for online moon viewing on International Observe the Moon night.

International Observe the Moon Night (InOMN 2019) is back, scheduled for October 5, 2019. It’ll be a special one this year, coming, as it does, in the year of the 50th anniversary of Apollo 11’s historic landing on the moon on July 20, 1969. There are many ways to celebrate the event, which we talk about below. In addition, the Virtual Telescope Project in Rome invites you to join InOMN 2019 online, live, from the comfort of your home, allowing you to enjoy the moon above Rome’s stunning skyline.

The online, free session is scheduled for October 5 2019, starting at 17:00 UTC; translate UTC to your time. To join the International Observe the Moon Night online, via the Virtual Telescope Project, you just need to enter at the date and time above the webTV page here.

NASA described this event on InOMN webpage:

International Observe the Moon Night is a worldwide celebration of lunar science and exploration, celestial observation, and our cultural and personal connections to the moon. One day each year, everyone on Earth is invited to observe, learn about, and celebrate the moon together.

This event always occurs in September or October, at a time when the moon is around first quarter – a great phase for evening observing. Furthermore, the best lunar observing is typically along the moon’s terminator (the line between night and day) where shadows are the longest, rather than at full moon.

You can participate by attending or hosting an International Observe the Moon Night event, or by registering as a lunar observer. Connect with fellow lunar enthusiasts around the world through NASA’s Facebook page, #ObserveTheMoon on your preferred social media platform, and the International Observe the Moon Night Flickr group.

To sum up, here are some next steps if you want to join International Observe the Moon Night 2019:

InOMN 2019: Join the Virtual Telescope Project to view the moon online, above the skyline of Rome

InOMN 2019: Attend an event in your location

InOMN 2019: Host an event

InOMN 2019: Register with NASA as a lunar observer

View NASA’s InOMN 2019 Facebook page

View NASA’s InOMN 2019 Flickr group

Bottom line: International Observe the Moon Night is October 5, 2019. Here are some ways to join in.

Join the Virtual Telescope Project to view the moon online, on International Observe the Moon night

from EarthSky https://ift.tt/2nzI8lC

Shapeshifting robots for Saturn’s moons

Shapeshifting has been an enduring device throughout literature, and we see shapeshifting everywhere in modern science fiction, for example, the shapeshifting android assassin in the Terminator movies. Even my 6-year-old grandson – who loves to spend an afternoon building with Legos – knows about shapeshifting robots. And now NASA engineers have gone into shapeshifting robots in a big way … for real. According a September 25, 2019, statement from NASA, a robotics team is testing a 3D-printed prototype of an unusual mini-robot at NASA’s Jet Propulsion Laboratory in Pasadena, California. The robot can roll, fly, float and swim, then morph into a single machine. NASA is calling this series of robots Shapeshifters.

No, not this guy. This is the T-1000 shapeshifter, a fictional character in the Terminator franchise. Image via Wikipedia.

Robotics technologist Ali Agha – who leads the Shapeshifter program for JPL – envisions Shapeshifter as a mission to Saturn’s largest moon Titan, the only other world in the solar system known to have liquid in the form of methane lakes, rivers and seas on its surface. NASA said Shapeshifter is:

… a developing concept for a transformational vehicle to explore treacherous, distant worlds.

A contraption that looks like a drone encased in an elongated hamster wheel rolls across the yard, then splits in half. Once separated, the two halves rise on small propellers, effectively becoming flying drones for aerial exploration. These 3D-printed parts are only the beginning; the team imagines a series of up to 12 robots that could transform into a swimming probe or a team of cave explorers.

Okay, maybe it sounds cooler than the actual prototype looks, for now. But NASA engineers are just starting down the path of shapeshifting robots, and who knows what the future will bring? In the meantime, here’s what the prototype looks like:

A prototype of the transforming robot Shapeshifter is tested in the robotics yard at NASA’s Jet Propulsion Laboratory. Shapeshifter is made of smaller robots that can morph into rolling spheres, flying drones, swimming submersibles and more. This flying amphibious robot is part of the early-stage research program NASA Innovative Advanced Concepts (NIAC), which offers several phases of funding to visionary concepts. NASA says the program “helps turn ideas that sound like science fiction into science fact.” Image via NASA/JPL-Caltech.

NASA’s most recent mission to Saturn and its moons was the Cassini mission, which began orbiting Saturn in 2004 and ended with a dramatic plunge into Saturn’s clouds in 2017. Cassini spent 13 years orbiting Saturn, flying different pathways among its moons. It flew by Titan over 100 times, with the goal, NASA said, of mapping its surface for future missions. Cassini found that Titan is similar to Earth but – because it’s so much farther from the sun, in a colder part of the solar system – Titan has key differences. It has cold rivers, lakes and rain made up of liquid methane and ethane, both of which exist on Earth in gaseous form. NASA said the moon’s hazy atmosphere could also conceal caves or icy volcanoes that spew ammonia or water instead of magma. Agha explained in the NASA statement why shapeshifting robots would be so useful there:

We have very limited information about the composition of the surface. Rocky terrain, methane lakes, cryovolcanoes – we potentially have all of these, but we don’t know for certain.

So we thought about how to create a system that is versatile and capable of traversing different types of terrain but also compact enough to launch on a rocket.

NASA said:

Agha and his Shapeshifter co-investigators, who include researchers from Stanford and Cornell universities, came up with the concept of a self-assembling robot made of smaller robots called ‘cobots.’ The cobots, each housing a small propeller, would be able to move independent of one another to fly along cliffsides of scientific interest. They could also go spelunking, forming a daisy chain to maintain contact with the surface. Or they could transform into a sphere to roll on flat surfaces and conserve energy.

For now, Shapeshifter is semi-autonomous, but its future design will depend on cobots that can auto-assemble without needing commands from Earth.

Agha’s ultimate vision includes a lander like the European Space Agency’s Huygens Probe, which touched down on Titan after being deployed via parachute by NASA’s Cassini spacecraft. This ‘mothercraft,’ as Agha calls it, would serve as an energy source for the cobots and carry the scientific instruments to perform in-depth sample analysis. But rather than staying in place, as landers usually do, this one would be portable. Flight is easier on Titan, where the atmosphere is dense and gravity is low. Agha calculates that 10 cobots could easily lift a lander the size of Huygens (roughly 9 feet, or 3 meters, wide) and gently carry it to different locations.

Jason Hofgartner is JPL’s lead scientist for Shapeshifter. He said:

It is often the case that some of the hardest places to get to are the most scientifically interesting because maybe they’re the youngest, or they’re in an area that was not well characterized from orbit.

Shapeshifter’s remarkable versatility enables access to all of these scientifically compelling places.

The next mission to Titan will be Dragonfly, NASA’s first rotorcraft lander, which is scheduled to launch in 2026. Shapeshifter won’t be aboard. It’s too new and too undeveloped. The next step for the Shapeshifter team is to submit its concept to NIAC’s Phase II selection process in 2020. After that, there are many more years of development ahead.

Still, the concept is a compelling one. And people like my grandson might be around long enough to see some amazing solar system exploration, using real Shapeshifters.

Artist’s concept of proposed design for future Shapeshifter robot, which would consist of many robots in one.

Bottom line: NASA is testing a 3D-printed prototype of unusual mini robots that can roll, fly, float and swim, then morph into a single machine. They’re called Shapeshifters. The team envisions them as a way to explore Saturn’s moons.

Via NASA/JPL-Caltech

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Shapeshifting has been an enduring device throughout literature, and we see shapeshifting everywhere in modern science fiction, for example, the shapeshifting android assassin in the Terminator movies. Even my 6-year-old grandson – who loves to spend an afternoon building with Legos – knows about shapeshifting robots. And now NASA engineers have gone into shapeshifting robots in a big way … for real. According a September 25, 2019, statement from NASA, a robotics team is testing a 3D-printed prototype of an unusual mini-robot at NASA’s Jet Propulsion Laboratory in Pasadena, California. The robot can roll, fly, float and swim, then morph into a single machine. NASA is calling this series of robots Shapeshifters.

No, not this guy. This is the T-1000 shapeshifter, a fictional character in the Terminator franchise. Image via Wikipedia.

Robotics technologist Ali Agha – who leads the Shapeshifter program for JPL – envisions Shapeshifter as a mission to Saturn’s largest moon Titan, the only other world in the solar system known to have liquid in the form of methane lakes, rivers and seas on its surface. NASA said Shapeshifter is:

… a developing concept for a transformational vehicle to explore treacherous, distant worlds.

A contraption that looks like a drone encased in an elongated hamster wheel rolls across the yard, then splits in half. Once separated, the two halves rise on small propellers, effectively becoming flying drones for aerial exploration. These 3D-printed parts are only the beginning; the team imagines a series of up to 12 robots that could transform into a swimming probe or a team of cave explorers.

Okay, maybe it sounds cooler than the actual prototype looks, for now. But NASA engineers are just starting down the path of shapeshifting robots, and who knows what the future will bring? In the meantime, here’s what the prototype looks like:

A prototype of the transforming robot Shapeshifter is tested in the robotics yard at NASA’s Jet Propulsion Laboratory. Shapeshifter is made of smaller robots that can morph into rolling spheres, flying drones, swimming submersibles and more. This flying amphibious robot is part of the early-stage research program NASA Innovative Advanced Concepts (NIAC), which offers several phases of funding to visionary concepts. NASA says the program “helps turn ideas that sound like science fiction into science fact.” Image via NASA/JPL-Caltech.

NASA’s most recent mission to Saturn and its moons was the Cassini mission, which began orbiting Saturn in 2004 and ended with a dramatic plunge into Saturn’s clouds in 2017. Cassini spent 13 years orbiting Saturn, flying different pathways among its moons. It flew by Titan over 100 times, with the goal, NASA said, of mapping its surface for future missions. Cassini found that Titan is similar to Earth but – because it’s so much farther from the sun, in a colder part of the solar system – Titan has key differences. It has cold rivers, lakes and rain made up of liquid methane and ethane, both of which exist on Earth in gaseous form. NASA said the moon’s hazy atmosphere could also conceal caves or icy volcanoes that spew ammonia or water instead of magma. Agha explained in the NASA statement why shapeshifting robots would be so useful there:

We have very limited information about the composition of the surface. Rocky terrain, methane lakes, cryovolcanoes – we potentially have all of these, but we don’t know for certain.

So we thought about how to create a system that is versatile and capable of traversing different types of terrain but also compact enough to launch on a rocket.

NASA said:

Agha and his Shapeshifter co-investigators, who include researchers from Stanford and Cornell universities, came up with the concept of a self-assembling robot made of smaller robots called ‘cobots.’ The cobots, each housing a small propeller, would be able to move independent of one another to fly along cliffsides of scientific interest. They could also go spelunking, forming a daisy chain to maintain contact with the surface. Or they could transform into a sphere to roll on flat surfaces and conserve energy.

For now, Shapeshifter is semi-autonomous, but its future design will depend on cobots that can auto-assemble without needing commands from Earth.

Agha’s ultimate vision includes a lander like the European Space Agency’s Huygens Probe, which touched down on Titan after being deployed via parachute by NASA’s Cassini spacecraft. This ‘mothercraft,’ as Agha calls it, would serve as an energy source for the cobots and carry the scientific instruments to perform in-depth sample analysis. But rather than staying in place, as landers usually do, this one would be portable. Flight is easier on Titan, where the atmosphere is dense and gravity is low. Agha calculates that 10 cobots could easily lift a lander the size of Huygens (roughly 9 feet, or 3 meters, wide) and gently carry it to different locations.

Jason Hofgartner is JPL’s lead scientist for Shapeshifter. He said:

It is often the case that some of the hardest places to get to are the most scientifically interesting because maybe they’re the youngest, or they’re in an area that was not well characterized from orbit.

Shapeshifter’s remarkable versatility enables access to all of these scientifically compelling places.

The next mission to Titan will be Dragonfly, NASA’s first rotorcraft lander, which is scheduled to launch in 2026. Shapeshifter won’t be aboard. It’s too new and too undeveloped. The next step for the Shapeshifter team is to submit its concept to NIAC’s Phase II selection process in 2020. After that, there are many more years of development ahead.

Still, the concept is a compelling one. And people like my grandson might be around long enough to see some amazing solar system exploration, using real Shapeshifters.

Artist’s concept of proposed design for future Shapeshifter robot, which would consist of many robots in one.

Bottom line: NASA is testing a 3D-printed prototype of unusual mini robots that can roll, fly, float and swim, then morph into a single machine. They’re called Shapeshifters. The team envisions them as a way to explore Saturn’s moons.

Via NASA/JPL-Caltech

from EarthSky https://ift.tt/2oY061v

This giant exoplanet shouldn’t exist, but it does

Artist’s concept of a Jupiter-like giant planet orbiting a red dwarf star. Image via CARMENES/RenderArea/J. Bollaín/C. Gallego/University of Bern.

Scientists have learned a lot in the past few decades about how planets form, but there is still much left to be figured out. Unexpected discoveries can sometimes make that more difficult, but also that much more interesting, of course. Now, another one of those discoveries has been made, an exoplanet 30 light-years away that – according to current theoretical models – shouldn’t exist, but does. An observatory in Spain discovered the planet, called GJ 3512b, and now researchers at the University of Bern in Switzerland are trying to solve the mystery.

The intriguing peer-reviewed results were published in Science on September 27, 2019.

This planet – GJ 3512b – was discovered by a Spanish-German research consortium called CARMENES using a telescope at Calar Alto Observatory in southern Spain. A major goal of CARMENES is to find planets orbiting the smallest stars, using an infrared spectrograph.

Artist’s concept via The Sun.

The puzzle here is that the planet is too big for its star, GJ 3512, according to the conventional understanding of modern-day astronomers. The star itself is a dwarf star, only about a tenth the mass of our sun. But this tiny star is orbited by a giant planet, half the mass of our solar system’s largest planet Jupiter. That shouldn’t be possible, scientists thought. As Christoph Mordasini, a professor at the University of Bern, explained:

Around such stars there should only be planets the size of the Earth or somewhat more massive super-Earths. GJ 3512b, however, is a giant planet with a mass about half as big as the one of Jupiter, and thus at least one order of magnitude more massive than the planets predicted by theoretical models for such small stars.

Mordasini continued:

Our model of the formation and evolution of planets predicts that around small stars a large number of small planets will be formed. Our model predicts that there should be no giant planets around such stars.

The exoplanet GJ 3512b was discovered by the CARMENES consortium with an instrument installed at the Calar Alto Observatory in southern Spain. Image via Pedro Amado/Marco Azzaro-IAA/CSIC/University of Bern.

Mordasini is one of the leading experts in the theory of planet formation, and CARMENES reached out to him about their unusual discovery.

So how to explain this?

The current model of planet formation – core accretion – says that planets form “from the bottom up,” starting off small and gradually accreting material to grow larger. But maybe that’s not the case with GJ 3512b. Maybe it formed by gravitational collapse. According to Mordasini:

A part of the gas disk in which the planets are formed collapses directly under its own gravitational force. A top-down process.

But there are problems with that idea, he said:

Why hasn’t the planet continued to grow and migrate closer to the star in this case? You would expect both if the gas disk had enough mass to become unstable under its gravity. The planet GJ 3512b is therefore an important discovery that should improve our understanding of how planets form around such stars.

Christoph Mordasini of the Physics Institute at the University of Bern. Image via University of Bern.

Giant exoplanets similar to Jupiter or Saturn have been discovered orbiting many stars now and are apparently common, at least in our own galaxy. Understanding how they form – around both larger and smaller stars – will help scientists better understand how planets form overall. The discovery of GJ 3512b shows, again, that we should also expect the unexpected, that the universe is full of surprises. When scientists find something that shouldn’t be able to exist – but does – that is an exciting moment in science.

Bottom line: Astronomers have discovered a giant exoplanet that current planet formation theory says shouldn’t be able to exist – but it does.

Source: A giant exoplanet orbiting a very low-mass star challenges planet formation models

Via University of Bern

from EarthSky https://ift.tt/2oareJU

Artist’s concept of a Jupiter-like giant planet orbiting a red dwarf star. Image via CARMENES/RenderArea/J. Bollaín/C. Gallego/University of Bern.

Scientists have learned a lot in the past few decades about how planets form, but there is still much left to be figured out. Unexpected discoveries can sometimes make that more difficult, but also that much more interesting, of course. Now, another one of those discoveries has been made, an exoplanet 30 light-years away that – according to current theoretical models – shouldn’t exist, but does. An observatory in Spain discovered the planet, called GJ 3512b, and now researchers at the University of Bern in Switzerland are trying to solve the mystery.

The intriguing peer-reviewed results were published in Science on September 27, 2019.

This planet – GJ 3512b – was discovered by a Spanish-German research consortium called CARMENES using a telescope at Calar Alto Observatory in southern Spain. A major goal of CARMENES is to find planets orbiting the smallest stars, using an infrared spectrograph.

Artist’s concept via The Sun.

The puzzle here is that the planet is too big for its star, GJ 3512, according to the conventional understanding of modern-day astronomers. The star itself is a dwarf star, only about a tenth the mass of our sun. But this tiny star is orbited by a giant planet, half the mass of our solar system’s largest planet Jupiter. That shouldn’t be possible, scientists thought. As Christoph Mordasini, a professor at the University of Bern, explained:

Around such stars there should only be planets the size of the Earth or somewhat more massive super-Earths. GJ 3512b, however, is a giant planet with a mass about half as big as the one of Jupiter, and thus at least one order of magnitude more massive than the planets predicted by theoretical models for such small stars.

Mordasini continued:

Our model of the formation and evolution of planets predicts that around small stars a large number of small planets will be formed. Our model predicts that there should be no giant planets around such stars.

The exoplanet GJ 3512b was discovered by the CARMENES consortium with an instrument installed at the Calar Alto Observatory in southern Spain. Image via Pedro Amado/Marco Azzaro-IAA/CSIC/University of Bern.

Mordasini is one of the leading experts in the theory of planet formation, and CARMENES reached out to him about their unusual discovery.

So how to explain this?

The current model of planet formation – core accretion – says that planets form “from the bottom up,” starting off small and gradually accreting material to grow larger. But maybe that’s not the case with GJ 3512b. Maybe it formed by gravitational collapse. According to Mordasini:

A part of the gas disk in which the planets are formed collapses directly under its own gravitational force. A top-down process.

But there are problems with that idea, he said:

Why hasn’t the planet continued to grow and migrate closer to the star in this case? You would expect both if the gas disk had enough mass to become unstable under its gravity. The planet GJ 3512b is therefore an important discovery that should improve our understanding of how planets form around such stars.

Christoph Mordasini of the Physics Institute at the University of Bern. Image via University of Bern.

Giant exoplanets similar to Jupiter or Saturn have been discovered orbiting many stars now and are apparently common, at least in our own galaxy. Understanding how they form – around both larger and smaller stars – will help scientists better understand how planets form overall. The discovery of GJ 3512b shows, again, that we should also expect the unexpected, that the universe is full of surprises. When scientists find something that shouldn’t be able to exist – but does – that is an exciting moment in science.

Bottom line: Astronomers have discovered a giant exoplanet that current planet formation theory says shouldn’t be able to exist – but it does.

Source: A giant exoplanet orbiting a very low-mass star challenges planet formation models

Via University of Bern

from EarthSky https://ift.tt/2oareJU

October guide to the bright planets

Click the name of a planet to learn more about its visibility in October 2019: Venus, Jupiter, Saturn, Mars and Mercury.

Watch for the moon to move up past Jupiter in the first few days of October.

The moon will be closest to Jupiter aroubnd September 3. Then, day by day, watch the moon move from the king planet Jupiter to the ringed planet Saturn. Read more.

Jupiter – the second-brightest planet after Venus – lords over the October 2019 evening sky. That’s because Venus sits close to the afterglow of sunset all month, leaving dazzling Jupiter to light up the evening sky. Jupiter pops out at dusk – brighter than any star – and stays out until mid-evening at mid-northern latitudes or until late evening at temperate latitudes in the Southern Hemisphere. Not sure which one is Jupiter? See the moon in Jupiter’s vicinity for several days, centered on or near October 3 and then again on or near Halloween.

Need more confirmation? Find a bright object you think is Jupiter, steady your binoculars – maybe sit down and anchor them on your knees, or prop your elbows on a fence railing – and aim them at that very bright light. If it is Jupiter, at least one or more of its four largest moons should pop into view.

At mid-northern latitudes in the Northern Hemisphere, Jupiter appears in the southwest sky at dusk. In early October, Jupiter sets around 9 p.m. (10 p.m. daylight saving time). By the month’s end, Jupiter sets nearly two hours earlier, around 7 p.m. (8 p.m. daylight saving time).

At temperate latitudes in the Southern Hemisphere, the king planet stays out till nearly midnight in early October, and then by late October, sets nearly two hours earlier, as well, around 10 p.m.

Try Stellarium Online for the view from your location.

That bright, fiercely twinkling red star – close to Jupiter on our sky’s dome this year – is Antares, the Heart of the Scorpion in the constellation Scorpius. In 2019, sky watchers have been watching Jupiter “wander” east and west relative to this zodiac star. In the first three months of 2019, Jupiter was traveling eastward, away from Antares. Starting on April 10, 2019, Jupiter reversed course, and began moving toward Antares. For four months (April 10 to August 11, 2019), Jupiter traveled in retrograde (or westward), closing the gap between itself and this star. Jupiter is now moving eastward again, away from Antares.

Look for the moon to pair up with Saturn on or near October 5, 2019. Read more.

Saturn. After you find Jupiter at dusk and nightfall, use this brilliant beauty of a planet to find another bright evening planet, Saturn. Saturn is not as bright as Jupiter, but the ringed planet shines on par with the sky’s brightest stars. Hold your fist at arm’s length. Saturn is nearly three fist-widths to the east of Jupiter. Because Saturn is the only bright-looking “star” to occupy this part of the sky, you’re not likely to mistake a bright star for Saturn.

Read more: When Jupiter and Saturn meet

Saturn – a golden world to the eye alone – pops out at nightfall and stays out until late evening. This planet still shines as brightly as a 1st-magnitude star, in other words, as brightly as our sky’s brightest stars.

Viewing Saturn’s rings soon? Read me 1st

At mid-northern latitudes, Saturn transits – reaches its highest point for the day – around sunset. In early October, Saturn sets around one hour before midnight (12 a.m. daylight saving time). Near the month’s end, Saturn plunges below the horizon around 9 p.m. (10 p.m. daylight saving time).

At temperate latitudes in the Southern Hemisphere, in early October, Saturn transits – climbs highest up – around sunset, and sets about one and one-half hours after the midnight hour. By late October, Saturn sinks below the horizon about one-half hour before midnight.

You won’t mistake Jupiter for Saturn. Jupiter is significantly the brighter pf these two worlds. Jupiter ranks the fourth-brightest celestial object after the sun, moon and Venus, respectively, and the king planet outshines Saturn by about 10 times. What’s more, at nightfall and early evening in October 2019, Jupiter shines well to the west of Saturn.

Watch for the first quarter moon to join up with Saturn on October 5, as shown on the sky chart above.

The steep tilt of the ecliptic gives the Southern Hemisphere the great big advantage for catching Mercury and Venus after sunset. .

Mercury and Venus are both evening planets – at least nominally – all through October 2019, but both hover too close to the afterglow of sunset to be easily viewed with the unaided eye at mid-northern latitudes. From the Southern Hemisphere, or the northern tropics, you have a much better chance of catching both Mercury and Venus with the eye alone as dusk gives way to darkness throughout October 2019.

Note that Venus – the brightest planet – is far brighter than Mercury. Nonetheless, Mercury shines as brilliantly as a 1st-magnitude star all month long, though it dims somewhat throughout the month. Look for Mercury and Venus way below Jupiter and rather close to the horizon as dusk deepens into nightfall.

Depending on where you live worldwide, the planets Mercury and Venus will be in conjunction on October 29 or 30, 2019. On either date, however, look for these two worlds to occupy a single binocular field of view. What’s more, the moon will be nearby these worlds in late October, so think photo opportunity! The sky chart below and the accompanying link provide more information.

The young moon swings in the vicinity of the planets Mercury, Venus and Jupiter in late October 2019. The above chart is for North American mid-northern latitudes. Click here for more information plus a Southern Hemisphere sky chart.

By the way, at Mercury’s most recent inferior conjunction on July 21, 2019, Mercury swung to the south of the sun’s disk as seen from Earth. But when Mercury reaches its next inferior conjunction on November 11, 2019, the innermost planet will swing directly in front of the sun, to stage a transit of Mercury. Transits of Mercury happen more frequently than transits of Venus; they happen 13 or 14 times per century. The last transit of Mercury happened on May 9, 2016, and – after the one on this upcoming November 11 – the next Mercury transit won’t be until November 13, 2032.

You might not see Mars until late October 2019. The waning crescent moon will point to Mars on October 23, 24 and 25. On October 26, look for the moon to swing close to Mars on the sky’s dome. Read more.

Where is Mars? Note that the above sky chart is for late October! That’s because late October might be your first decent chance to catch this world before sunrise. Mars swung on the far side of the sun at superior conjunction on September 2, 2019, to transition from the evening to morning sky. Hiding in the glare of sunrise, Mars probably won’t become visible in the morning sky until late October or November 2019. Mars will be more easily viewed from the Northern Hemisphere and southern tropics than at temperate latitudes in the Southern Hemisphere.

What do we mean by bright planet? By bright planet, we mean any solar system planet that is easily visible without an optical aid and that has been watched by our ancestors since time immemorial. In their outward order from the sun, the five bright planets are Mercury, Venus, Mars, Jupiter and Saturn. These planets actually do appear bright in our sky. They are typically as bright as – or brighter than – the brightest stars. Plus, these relatively nearby worlds tend to shine with a steadier light than the distant, twinkling stars. You can spot them, and come to know them as faithful friends, if you try.

Skywatcher, by Predrag Agatonovic.

Bottom line: In October 2019, two planets – Jupiter and Saturn – are easy to see throughout the month. They both come out at nightfall and are out until well after nightfall. Mercury and Venus are pretty much sitting in the afterglow of sunset, whereas Mars is hiding in the glare of sunrise. Click here for recommended almanacs; they can help you know when the planets rise and set in your sky.

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Click the name of a planet to learn more about its visibility in October 2019: Venus, Jupiter, Saturn, Mars and Mercury.

Watch for the moon to move up past Jupiter in the first few days of October.

The moon will be closest to Jupiter aroubnd September 3. Then, day by day, watch the moon move from the king planet Jupiter to the ringed planet Saturn. Read more.

Jupiter – the second-brightest planet after Venus – lords over the October 2019 evening sky. That’s because Venus sits close to the afterglow of sunset all month, leaving dazzling Jupiter to light up the evening sky. Jupiter pops out at dusk – brighter than any star – and stays out until mid-evening at mid-northern latitudes or until late evening at temperate latitudes in the Southern Hemisphere. Not sure which one is Jupiter? See the moon in Jupiter’s vicinity for several days, centered on or near October 3 and then again on or near Halloween.

Need more confirmation? Find a bright object you think is Jupiter, steady your binoculars – maybe sit down and anchor them on your knees, or prop your elbows on a fence railing – and aim them at that very bright light. If it is Jupiter, at least one or more of its four largest moons should pop into view.

At mid-northern latitudes in the Northern Hemisphere, Jupiter appears in the southwest sky at dusk. In early October, Jupiter sets around 9 p.m. (10 p.m. daylight saving time). By the month’s end, Jupiter sets nearly two hours earlier, around 7 p.m. (8 p.m. daylight saving time).

At temperate latitudes in the Southern Hemisphere, the king planet stays out till nearly midnight in early October, and then by late October, sets nearly two hours earlier, as well, around 10 p.m.

Try Stellarium Online for the view from your location.

That bright, fiercely twinkling red star – close to Jupiter on our sky’s dome this year – is Antares, the Heart of the Scorpion in the constellation Scorpius. In 2019, sky watchers have been watching Jupiter “wander” east and west relative to this zodiac star. In the first three months of 2019, Jupiter was traveling eastward, away from Antares. Starting on April 10, 2019, Jupiter reversed course, and began moving toward Antares. For four months (April 10 to August 11, 2019), Jupiter traveled in retrograde (or westward), closing the gap between itself and this star. Jupiter is now moving eastward again, away from Antares.

Look for the moon to pair up with Saturn on or near October 5, 2019. Read more.

Saturn. After you find Jupiter at dusk and nightfall, use this brilliant beauty of a planet to find another bright evening planet, Saturn. Saturn is not as bright as Jupiter, but the ringed planet shines on par with the sky’s brightest stars. Hold your fist at arm’s length. Saturn is nearly three fist-widths to the east of Jupiter. Because Saturn is the only bright-looking “star” to occupy this part of the sky, you’re not likely to mistake a bright star for Saturn.

Read more: When Jupiter and Saturn meet

Saturn – a golden world to the eye alone – pops out at nightfall and stays out until late evening. This planet still shines as brightly as a 1st-magnitude star, in other words, as brightly as our sky’s brightest stars.

Viewing Saturn’s rings soon? Read me 1st

At mid-northern latitudes, Saturn transits – reaches its highest point for the day – around sunset. In early October, Saturn sets around one hour before midnight (12 a.m. daylight saving time). Near the month’s end, Saturn plunges below the horizon around 9 p.m. (10 p.m. daylight saving time).

At temperate latitudes in the Southern Hemisphere, in early October, Saturn transits – climbs highest up – around sunset, and sets about one and one-half hours after the midnight hour. By late October, Saturn sinks below the horizon about one-half hour before midnight.

You won’t mistake Jupiter for Saturn. Jupiter is significantly the brighter pf these two worlds. Jupiter ranks the fourth-brightest celestial object after the sun, moon and Venus, respectively, and the king planet outshines Saturn by about 10 times. What’s more, at nightfall and early evening in October 2019, Jupiter shines well to the west of Saturn.

Watch for the first quarter moon to join up with Saturn on October 5, as shown on the sky chart above.

The steep tilt of the ecliptic gives the Southern Hemisphere the great big advantage for catching Mercury and Venus after sunset. .

Mercury and Venus are both evening planets – at least nominally – all through October 2019, but both hover too close to the afterglow of sunset to be easily viewed with the unaided eye at mid-northern latitudes. From the Southern Hemisphere, or the northern tropics, you have a much better chance of catching both Mercury and Venus with the eye alone as dusk gives way to darkness throughout October 2019.

Note that Venus – the brightest planet – is far brighter than Mercury. Nonetheless, Mercury shines as brilliantly as a 1st-magnitude star all month long, though it dims somewhat throughout the month. Look for Mercury and Venus way below Jupiter and rather close to the horizon as dusk deepens into nightfall.

Depending on where you live worldwide, the planets Mercury and Venus will be in conjunction on October 29 or 30, 2019. On either date, however, look for these two worlds to occupy a single binocular field of view. What’s more, the moon will be nearby these worlds in late October, so think photo opportunity! The sky chart below and the accompanying link provide more information.

The young moon swings in the vicinity of the planets Mercury, Venus and Jupiter in late October 2019. The above chart is for North American mid-northern latitudes. Click here for more information plus a Southern Hemisphere sky chart.

By the way, at Mercury’s most recent inferior conjunction on July 21, 2019, Mercury swung to the south of the sun’s disk as seen from Earth. But when Mercury reaches its next inferior conjunction on November 11, 2019, the innermost planet will swing directly in front of the sun, to stage a transit of Mercury. Transits of Mercury happen more frequently than transits of Venus; they happen 13 or 14 times per century. The last transit of Mercury happened on May 9, 2016, and – after the one on this upcoming November 11 – the next Mercury transit won’t be until November 13, 2032.

You might not see Mars until late October 2019. The waning crescent moon will point to Mars on October 23, 24 and 25. On October 26, look for the moon to swing close to Mars on the sky’s dome. Read more.

Where is Mars? Note that the above sky chart is for late October! That’s because late October might be your first decent chance to catch this world before sunrise. Mars swung on the far side of the sun at superior conjunction on September 2, 2019, to transition from the evening to morning sky. Hiding in the glare of sunrise, Mars probably won’t become visible in the morning sky until late October or November 2019. Mars will be more easily viewed from the Northern Hemisphere and southern tropics than at temperate latitudes in the Southern Hemisphere.

What do we mean by bright planet? By bright planet, we mean any solar system planet that is easily visible without an optical aid and that has been watched by our ancestors since time immemorial. In their outward order from the sun, the five bright planets are Mercury, Venus, Mars, Jupiter and Saturn. These planets actually do appear bright in our sky. They are typically as bright as – or brighter than – the brightest stars. Plus, these relatively nearby worlds tend to shine with a steadier light than the distant, twinkling stars. You can spot them, and come to know them as faithful friends, if you try.

Skywatcher, by Predrag Agatonovic.

Bottom line: In October 2019, two planets – Jupiter and Saturn – are easy to see throughout the month. They both come out at nightfall and are out until well after nightfall. Mercury and Venus are pretty much sitting in the afterglow of sunset, whereas Mars is hiding in the glare of sunrise. Click here for recommended almanacs; they can help you know when the planets rise and set in your sky.

Don’t miss anything. Subscribe to EarthSky News by email

Visit EarthSky’s Best Places to Stargaze, and recommend a place we can all enjoy.

Help EarthSky keep going! Donate now.

Post your planet photos at EarthSky Community Photos

from EarthSky https://ift.tt/1YD00CF

Researchers to spend a year trapped in Arctic ice

This German research icebreaker, Polarstern, will spend a year trapped in Arctic sea ice in what researchers are calling “the biggest polar expedition of all time.” Image via ESA.

In October 2019, the research icebreaker Polarstern (“Polar Star”) will drop anchor at an ice floe in the northern Laptev Sea, marking the beginning of a year-long international investigation into Earth’s Arctic. The expedition is called MOSAiC – Multidisciplinary drifting Observatory for the Study of Arctic Climate – and it’ll spend the coming year trapped and drifting in the sea ice. In a statement about the expedition, released by the European Space Agency (ESA) on September 24, 2019, scientists said it is:

… the biggest shipborne polar expedition of all time.

And – although there’ve been many expeditions to the Arctic over time – this one is sure to be among the harshest. Roughly 100 people will be researching, working and living on board the icebreaker and on the sea ice itself. They’ll brave the upcoming polar winter, which will feature 24-hour darkness, storms and temperatures that can drop to -40 degrees Fahrenheit (also -40 degrees Celsius). The expedition will include scientists from many nations. It’s being spearheaded by the Alfred Wegener Institute (AWI) of the Helmholtz Centre for Polar and Marine Research, based in Bremerhaven, Germany. Christian Haas – a sea ice expert at AWI – commented:

We want to better understand the processes and energy flows between the ocean, ice and atmosphere – and how they change over the course of the seasons.

We will also compare the data with satellite data, in particular with ESA’s CryoSat, which was specifically launched to measure ice thickness. This will allow us to observe how the ice grows and becomes thinner.

The European Space Agency (ESA) also has a hand in this expedition, with a range of experiments. Tânia Casal, science campaign coordinator for ESA, commented:

The MOSAiC expedition offers a unique opportunity to considerably improve our understanding of ocean–ice-snow–atmosphere processes and this will contribute to a more accurate modelling of future Arctic climate scenarios.

We want to make sure that data associated with these processes delivered by ESA satellites and by the Copernicus Sentinels as well as from missions under development have the best possible impact. So we are contributing to the expedition with a range of calibration and validation activities.

For example, as Dr. Haas mentions that arrangements have been made for measurements to be taken that will be used to validate CryoSat, but also that validate the Copernicus Sentinel-1 radar mission.

View larger. | The potential drift route of the research vessel Polarstern can be roughly estimated in advance by reconstructing the course that the ice followed from the vessel’s starting point in past years. This involves the use of satellite data, which depicts the ice drift in the Arctic on a daily basis. The image shows sample drift trajectories for the years 2005 to 2017 and a potential starting point near 85°N/130°E. The start date for the drift analysis is always October 1. Image via ESA.

The state of Earth’s climate was recently outlined in a detailed new report produced for the U.N. Climate Action Summit, held in New York City on September 23, 2019. ESA said:

[The report] says that the five-year period from 2014 to 2019 is the warmest on record and that sea-level rise has accelerated significantly over the same period as carbon dioxide emissions have hit new highs.

However, the Arctic is warming twice as fast as the global average. Since Earth’s climate works as a system, the consequences of this rapid warming are not only being felt in this remote polar region, but also across the planet.

Needless to say, a better scientific understanding of the complexities of the fragile Arctic environment is critical for policy decisions on climate-change mitigation and adaptation, and for setting up a framework for managing Arctic development sustainably.

Scientists working in the long polar night. This image – from 2013, in Antarctica – shows scientists studying the properties of snow for later validation of ESA’s CryoSat satellite data. The icebreaker vessel Polarstern is in the background. Image via ESA.

Bottom line: The largest-ever shipborne expedition to the Arctic will drop anchor at an ice floe in the northern Laptev Sea in October 2019, then spend a year trapped in Arctic ice.

Read more: What climate change in the Arctic means for the rest of us

Via ESA

from EarthSky https://ift.tt/2mUmQif

This German research icebreaker, Polarstern, will spend a year trapped in Arctic sea ice in what researchers are calling “the biggest polar expedition of all time.” Image via ESA.

In October 2019, the research icebreaker Polarstern (“Polar Star”) will drop anchor at an ice floe in the northern Laptev Sea, marking the beginning of a year-long international investigation into Earth’s Arctic. The expedition is called MOSAiC – Multidisciplinary drifting Observatory for the Study of Arctic Climate – and it’ll spend the coming year trapped and drifting in the sea ice. In a statement about the expedition, released by the European Space Agency (ESA) on September 24, 2019, scientists said it is:

… the biggest shipborne polar expedition of all time.

And – although there’ve been many expeditions to the Arctic over time – this one is sure to be among the harshest. Roughly 100 people will be researching, working and living on board the icebreaker and on the sea ice itself. They’ll brave the upcoming polar winter, which will feature 24-hour darkness, storms and temperatures that can drop to -40 degrees Fahrenheit (also -40 degrees Celsius). The expedition will include scientists from many nations. It’s being spearheaded by the Alfred Wegener Institute (AWI) of the Helmholtz Centre for Polar and Marine Research, based in Bremerhaven, Germany. Christian Haas – a sea ice expert at AWI – commented:

We want to better understand the processes and energy flows between the ocean, ice and atmosphere – and how they change over the course of the seasons.

We will also compare the data with satellite data, in particular with ESA’s CryoSat, which was specifically launched to measure ice thickness. This will allow us to observe how the ice grows and becomes thinner.

The European Space Agency (ESA) also has a hand in this expedition, with a range of experiments. Tânia Casal, science campaign coordinator for ESA, commented:

The MOSAiC expedition offers a unique opportunity to considerably improve our understanding of ocean–ice-snow–atmosphere processes and this will contribute to a more accurate modelling of future Arctic climate scenarios.

We want to make sure that data associated with these processes delivered by ESA satellites and by the Copernicus Sentinels as well as from missions under development have the best possible impact. So we are contributing to the expedition with a range of calibration and validation activities.

For example, as Dr. Haas mentions that arrangements have been made for measurements to be taken that will be used to validate CryoSat, but also that validate the Copernicus Sentinel-1 radar mission.

View larger. | The potential drift route of the research vessel Polarstern can be roughly estimated in advance by reconstructing the course that the ice followed from the vessel’s starting point in past years. This involves the use of satellite data, which depicts the ice drift in the Arctic on a daily basis. The image shows sample drift trajectories for the years 2005 to 2017 and a potential starting point near 85°N/130°E. The start date for the drift analysis is always October 1. Image via ESA.

The state of Earth’s climate was recently outlined in a detailed new report produced for the U.N. Climate Action Summit, held in New York City on September 23, 2019. ESA said:

[The report] says that the five-year period from 2014 to 2019 is the warmest on record and that sea-level rise has accelerated significantly over the same period as carbon dioxide emissions have hit new highs.

However, the Arctic is warming twice as fast as the global average. Since Earth’s climate works as a system, the consequences of this rapid warming are not only being felt in this remote polar region, but also across the planet.

Needless to say, a better scientific understanding of the complexities of the fragile Arctic environment is critical for policy decisions on climate-change mitigation and adaptation, and for setting up a framework for managing Arctic development sustainably.

Scientists working in the long polar night. This image – from 2013, in Antarctica – shows scientists studying the properties of snow for later validation of ESA’s CryoSat satellite data. The icebreaker vessel Polarstern is in the background. Image via ESA.

Bottom line: The largest-ever shipborne expedition to the Arctic will drop anchor at an ice floe in the northern Laptev Sea in October 2019, then spend a year trapped in Arctic ice.

Read more: What climate change in the Arctic means for the rest of us

Via ESA

from EarthSky https://ift.tt/2mUmQif