James Martin in Albuquerque, New Mexico, caught this photo of Saturn at its 2017 opposition, when the rings were maximally tilted toward Earth. Opposition marks the middle of the best time of year to see an outer planet. The 2020 opposition will happen on July 20.
It’s that magical time of year again, when our solar system’s most beautiful planet – Saturn – is becoming well placed for viewing in our sky. Saturn looks starlike to the eye alone, but it shines steadily, as planets tend to do, and it has a distinct golden color. So Saturn is a lovely object to view with the eye alone. Binoculars will enhance its color, and even small telescopes will show you Saturn’s rings. Veteran observer Alan MacRobert at SkyandTelescope.com has written:
The rings of Saturn should be visible in even the smallest telescope at 25x [magnified by 25 times]. A good 3-inch scope at 50x [magnified by 50 times] can show them as a separate structure detached on all sides from the ball of the planet.
You want to see Saturn’s rings. We know you do! With the moon passing Saturn this week, it’s a good time to identify the planet with the eye alone. See the chart below:
The moon sweeps past Saturn on the nights of June 7 and 8, 2020. Read more.
See, on the chart above, how Saturn is near a brighter planet, Jupiter? These two planets will be near each other throughout 2020. Jupiter outshines all the stars, so its proximity to Saturn will make finding Saturn a breeze. And, before this year ends, Jupiter and Saturn will have a great conjunction?
Okay, got Saturn? It’ll be great fun to watch it and Jupiter throughout the rest of 2020. Now … about that telescope. One possibility is to start scouting out a star party near you, where amateur astronomers are set up to show you telescopic objects. Check the club map at NASA’s Night Sky Network to find star parties. Or try this list of astronomy clubs by state from the Astronomical League. Or call a local university or science museum and ask about star parties. Or maybe a neighbor, or friend, has a telescope stashed in a closet? More possibilities:
Astronomy Clubs Near Me & Organizations, from SkyandTelescope.com.
2018 Astronomy Club Directory, from Go-Astronomy.com.
Astronomy Clubs Near Me, from LoveTheNightSky.com.
Okay, so you can find Saturn in the sky, and you’ve found a star party to attend. Here are some things to think about before your Saturn ring-viewing session:
1. Telescope. Don’t expect to see the rings in binoculars. You really do need a telescope. A bigger telescope will show you more than a smaller telescope. Check out the contrast between the two photos below.
These images suggest how the ringed planet Saturn might look when seen through a telescope with an aperture 4 inches (100 mm) in diameter (top) and through a larger instrument with an 8-inch (200 mm) aperture (bottom). Image via SkyandTelescope.com/ NASA/ Hubble Space Telescope.
2. Tilt. Notice the tilt of the rings. As with so much in space (and on Earth), the appearance of Saturn’s rings from Earth is cyclical. In 2017, the north side of the rings opened up most widely (27 degrees), as seen from Earth. That’s the most open this face of the rings has been since since 1988. In 2020, we’re past the peak of the north ring face opening, but Saturn’s rings are still inclined at nearly 22 degrees from edge-on, still exhibiting their northern face. By the year 2025, the rings will appear edge-on as seen from Earth. At such times, because the rings are so thin, it’s possible to view Saturn through a telescope as if it has no rings at all! After that, we’ll begin to see the south side of Saturn’s rings and their openness will gradually increase to a maximum inclination of 27 degrees by May 2032.
The tilt of Saturn’s rings has a great impact on the planet’s overall brightness as seen from Earth. In years when Saturn’s rings are edge-on as seen from Earth (2009 and 2025), Saturn does appear considerably dimmer than in years when Saturn’s rings are maximally tilted toward Earth (2017 and 2032). These Saturn views were simulated with a computer program written by Tom Ruen. Image via Wikimedia Commons.
3. 3D. Ask yourself … do Saturn’s rings look three-dimensional? Again quoting Alan MacRobert at SkyandTelescope.com:
Saturn has a more three-dimensional appearance than any other object in the sky — at least that’s how it looks to me with a 6-inch ‘scope on a night of fine seeing.
4. Seeing. What was Alan talking about in that quote above when he mentioned seeing? Both amateur and professional astronomers talk about the night’s seeing, which affects how clearly and sharply you can see a telescopic image. Seeing isn’t a quality of the telescope; it’s a quality of the air above you. It’s the reason the stars twinkle more on some nights than others. When the air is particularly turbulent, astronomers say there’s bad seeing. The images at the telescope shimmy and dance. When the air is particularly still, astronomers say there’s good seeing. Seeing can shift from moment to moment, as parcels of air move above you. So, as you’re gazing at Saturn, stand as quietly as you can – for as long as you can – and just look. You’ll notice moments when the image suddenly comes into sharper focus.
Turbulent air makes for poor seeing. But the air above you can also “settle” suddenly. When viewing Saturn, wait for those moments. Image via AstronomyNotes.com.
5. Other things to think about. Once you get comfortable viewing Saturn – assuming you’re able to view it again and again, with a telescope of your own – you’ll begin to notice details in the rings. Today, thanks to spacecraft, we know that Saturn’s rings are incredibly detailed. But, as you stand at your telescope gazing upward, you might be thrilled to witness just one primary division in the rings, the Cassini Division between the A and B rings, named for its French discoverer Jean Cassini. Seeing this dark division is a good test of the night’s seeing and your telescope’s optical quality, and also of your own eyes’ ability to simply look and notice what you see. By the way, if you’re looking at the rings – which means you’re viewing Saturn through a telescope – look also for one or more of Saturn’s many moons, most notably Titan.
Have fun!
Alas, you won’t see Saturn look like this through a telescope. This is a spacecraft view, from Cassini in 2016, showing Saturn’s northern hemisphere. Image via NASA/ JPL-Caltech/ Space Science Institute.
Bottom line: In 2020, Saturn’s opposition – marking the middle of the best time of year to see it – comes on July 20. Here are some tips for beginners who want to see Saturn’s rings.
Read more … Viewing Saturn: Rings, Planet and Moons
Help EarthSky keep going! Please donate.
from EarthSky https://ift.tt/2Y9hEUV
James Martin in Albuquerque, New Mexico, caught this photo of Saturn at its 2017 opposition, when the rings were maximally tilted toward Earth. Opposition marks the middle of the best time of year to see an outer planet. The 2020 opposition will happen on July 20.
It’s that magical time of year again, when our solar system’s most beautiful planet – Saturn – is becoming well placed for viewing in our sky. Saturn looks starlike to the eye alone, but it shines steadily, as planets tend to do, and it has a distinct golden color. So Saturn is a lovely object to view with the eye alone. Binoculars will enhance its color, and even small telescopes will show you Saturn’s rings. Veteran observer Alan MacRobert at SkyandTelescope.com has written:
The rings of Saturn should be visible in even the smallest telescope at 25x [magnified by 25 times]. A good 3-inch scope at 50x [magnified by 50 times] can show them as a separate structure detached on all sides from the ball of the planet.
You want to see Saturn’s rings. We know you do! With the moon passing Saturn this week, it’s a good time to identify the planet with the eye alone. See the chart below:
The moon sweeps past Saturn on the nights of June 7 and 8, 2020. Read more.
See, on the chart above, how Saturn is near a brighter planet, Jupiter? These two planets will be near each other throughout 2020. Jupiter outshines all the stars, so its proximity to Saturn will make finding Saturn a breeze. And, before this year ends, Jupiter and Saturn will have a great conjunction?
Okay, got Saturn? It’ll be great fun to watch it and Jupiter throughout the rest of 2020. Now … about that telescope. One possibility is to start scouting out a star party near you, where amateur astronomers are set up to show you telescopic objects. Check the club map at NASA’s Night Sky Network to find star parties. Or try this list of astronomy clubs by state from the Astronomical League. Or call a local university or science museum and ask about star parties. Or maybe a neighbor, or friend, has a telescope stashed in a closet? More possibilities:
Astronomy Clubs Near Me & Organizations, from SkyandTelescope.com.
2018 Astronomy Club Directory, from Go-Astronomy.com.
Astronomy Clubs Near Me, from LoveTheNightSky.com.
Okay, so you can find Saturn in the sky, and you’ve found a star party to attend. Here are some things to think about before your Saturn ring-viewing session:
1. Telescope. Don’t expect to see the rings in binoculars. You really do need a telescope. A bigger telescope will show you more than a smaller telescope. Check out the contrast between the two photos below.
These images suggest how the ringed planet Saturn might look when seen through a telescope with an aperture 4 inches (100 mm) in diameter (top) and through a larger instrument with an 8-inch (200 mm) aperture (bottom). Image via SkyandTelescope.com/ NASA/ Hubble Space Telescope.
2. Tilt. Notice the tilt of the rings. As with so much in space (and on Earth), the appearance of Saturn’s rings from Earth is cyclical. In 2017, the north side of the rings opened up most widely (27 degrees), as seen from Earth. That’s the most open this face of the rings has been since since 1988. In 2020, we’re past the peak of the north ring face opening, but Saturn’s rings are still inclined at nearly 22 degrees from edge-on, still exhibiting their northern face. By the year 2025, the rings will appear edge-on as seen from Earth. At such times, because the rings are so thin, it’s possible to view Saturn through a telescope as if it has no rings at all! After that, we’ll begin to see the south side of Saturn’s rings and their openness will gradually increase to a maximum inclination of 27 degrees by May 2032.
The tilt of Saturn’s rings has a great impact on the planet’s overall brightness as seen from Earth. In years when Saturn’s rings are edge-on as seen from Earth (2009 and 2025), Saturn does appear considerably dimmer than in years when Saturn’s rings are maximally tilted toward Earth (2017 and 2032). These Saturn views were simulated with a computer program written by Tom Ruen. Image via Wikimedia Commons.
3. 3D. Ask yourself … do Saturn’s rings look three-dimensional? Again quoting Alan MacRobert at SkyandTelescope.com:
Saturn has a more three-dimensional appearance than any other object in the sky — at least that’s how it looks to me with a 6-inch ‘scope on a night of fine seeing.
4. Seeing. What was Alan talking about in that quote above when he mentioned seeing? Both amateur and professional astronomers talk about the night’s seeing, which affects how clearly and sharply you can see a telescopic image. Seeing isn’t a quality of the telescope; it’s a quality of the air above you. It’s the reason the stars twinkle more on some nights than others. When the air is particularly turbulent, astronomers say there’s bad seeing. The images at the telescope shimmy and dance. When the air is particularly still, astronomers say there’s good seeing. Seeing can shift from moment to moment, as parcels of air move above you. So, as you’re gazing at Saturn, stand as quietly as you can – for as long as you can – and just look. You’ll notice moments when the image suddenly comes into sharper focus.
Turbulent air makes for poor seeing. But the air above you can also “settle” suddenly. When viewing Saturn, wait for those moments. Image via AstronomyNotes.com.
5. Other things to think about. Once you get comfortable viewing Saturn – assuming you’re able to view it again and again, with a telescope of your own – you’ll begin to notice details in the rings. Today, thanks to spacecraft, we know that Saturn’s rings are incredibly detailed. But, as you stand at your telescope gazing upward, you might be thrilled to witness just one primary division in the rings, the Cassini Division between the A and B rings, named for its French discoverer Jean Cassini. Seeing this dark division is a good test of the night’s seeing and your telescope’s optical quality, and also of your own eyes’ ability to simply look and notice what you see. By the way, if you’re looking at the rings – which means you’re viewing Saturn through a telescope – look also for one or more of Saturn’s many moons, most notably Titan.
Have fun!
Alas, you won’t see Saturn look like this through a telescope. This is a spacecraft view, from Cassini in 2016, showing Saturn’s northern hemisphere. Image via NASA/ JPL-Caltech/ Space Science Institute.
Bottom line: In 2020, Saturn’s opposition – marking the middle of the best time of year to see it – comes on July 20. Here are some tips for beginners who want to see Saturn’s rings.
Read more … Viewing Saturn: Rings, Planet and Moons
Help EarthSky keep going! Please donate.
from EarthSky https://ift.tt/2Y9hEUV
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