Cassini’s Grand Finale (Why I Missed Wednesday’s APotW)

Hello! You’ll noticed that I skipped Astronomy Pictures of the Week on Wednesday. That… was on purpose.

Today was Cassini’s last day alive. This morning, Cassini plunged into Saturn, sending back some amazing data, but, in the process, ending its life.

Cassini was launched on October 15th, 1997. For two decades, Cassini revealed the wonders of the greatest planet and planetary system in our solar system to us. We learned so much.

But, now, it’s over…

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Astronomy Picture of the Week – Saturn-lit Tethys

Here’s a pretty cool image

Cassini gazes across the icy rings of Saturn toward the icy moon Tethys, whose night side is illuminated by Saturnshine, or sunlight reflected by the planet.

Tethys was on the far side of Saturn with respect to Cassini here; an observer looking upward from the moon’s surface toward Cassini would see Saturn’s illuminated disk filling the sky.

Tethys was brightened by a factor of two in this image to increase its visibility. A sliver of the moon’s sunlit northern hemisphere is seen at top. A bright wedge of Saturn’s sunlit side is seen at lower left.

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Astronomy Picture of the Week – Highlighting Titan’s Hazes

Back to Cassini’s Grand Finale… today we’re highlighting Titan

NASA’s Cassini spacecraft looks toward the night side of Saturn’s moon Titan in a view that highlights the extended, hazy nature of the moon’s atmosphere. During its long mission at Saturn, Cassini has frequently observed Titan at viewing angles like this, where the atmosphere is backlit by the Sun, in order to make visible the structure of the hazes.

Titan’s high-altitude haze layer appears blue here, whereas the main atmospheric haze is orange. The difference in color could be due to particle sizes in the haze. The blue haze likely consists of smaller particles than the orange haze.

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Astronomy Picture(s and Video) of the Week: US Total Solar Eclipse, August 21, 2017

Taking a detour from Cassini’s Grand Finale to celebrate the solar eclipse we had in the US just this past Monday. I’m sad to say that, from my vantage point (Long Island, New York), it was pretty underwhelming. I wish I’d had the money and time to travel to somewhere along the path of totality and really observe it. Hopefully I’ll be able to for the next one. I’m quite positive that this isn’t my first, but it could just be that I watched clips of one when I was younger. Did the last total solar eclipse in the US happen sometime within the last 30 years?

Hm…

Anyways…

The eclipse has been called the “Great American Eclipse” which like… they know that Canada and South America have had total solar eclipses, too… right? I mean… the United States isn’t the only country in America you know… But anyways

The event’s shadow began to cover land on the¬†Oregon¬†coast as a partial eclipse at 4:06¬†p.m.¬†UTC¬†(9:06¬†a.m.¬†PDT), and its land coverage ended as a partial eclipse along the South Carolina coast at about 6:44¬†p.m. UTC (2:44¬†p.m.¬†EDT).¬†Visibility as a partial eclipse in¬†Honolulu, Hawaii¬†began with sunrise at 4:20¬†p.m. UTC (6:20¬†a.m.¬†HST) and ended by 5:25¬†p.m. UTC (7:25¬†a.m. HST).

Okay so…

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Astronomy Picture of the Week – More Textures in the C Ring

I also realize I missed last week’s APotW. Apologies…

Continuing on with the Grand Finale

This image was taken on May 29, 2017, with the Cassini spacecraft narrow-angle camera. The image was acquired on the sunlit side of the rings from a distance of about 39,800 miles (64,100 kilometers) away from the area pictured. The image scale is 1,460 feet (445 meters) per pixel. The phase angle, or sun-ring-spacecraft angle, is 137 degrees.

(See the bottom of the post for the links to download the associated .tif images…)

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Astronomy Picture of the Week – Puzzled Iapetus

Yet another one from Cassini’s Grand Finale. Yup, it’s still going

Iapetus is a world of contrast, with light and dark regions fitting together like cosmic puzzle pieces.

Cassini Regio on Iapetus (914 miles or 1,471 kilometers across) is covered in a layer of dark, dusty material creating a stark contrast to the much brighter region that surrounds it. This leads to the moon’s distinctive, two-toned appearance. To learn more about the cause of the contrast between regions, see Encountering Iapetus.

This view looks toward Saturn-facing hemisphere of Iapetus. North on Iapetus is up and rotated 20 degrees to the right. The image was taken in visible light with the Cassini spacecraft narrow-angle camera on March 11, 2017.

The view was obtained at a distance of approximately 1.6 million miles (2.6 million kilometers) from Iapetus. Image scale is 9 miles (15 kilometers) per pixel.

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Self Care – Astronomy Picture(s and Video) of the Week: Milky Way-like Galaxies in Early Universe Embedded in ‚ÄėSuper Halos‚Äô

Yet another really cool Astronomy discovery, this one announced back on March 23rd

Composite ALMA and optical image of a young Milky Way-like galaxy 12 billion light-years away and a background quasar 12.5 billion light-years away. Light from the quasar passed through the galaxy's gas on its way to Earth, revealing the presence of the galaxy to astronomers. New ALMA observations of the galaxy's ionized carbon (green) and dust continuum (blue) emission show that the dusty, star-forming disk of the galaxy is vastly offset from the gas detected by quasar absorption at optical wavelengths (red). This indicates that a massive halo of gas surrounds the galaxy. The optical data are from the Keck I Telescope at the W.M. Keck Observatory. Credit: ALMA (ESO/NAOJ/NRAO), M. Neeleman & J. Xavier Prochaska; Keck Observatory

Composite ALMA and optical image of a young Milky Way-like galaxy 12 billion light-years away and a background quasar 12.5 billion light-years away. Light from the quasar passed through the galaxy’s gas on its way to Earth, revealing the presence of the galaxy to astronomers. New ALMA observations of the galaxy’s ionized carbon (green) and dust continuum (blue) emission show that the dusty, star-forming disk of the galaxy is vastly offset from the gas detected by quasar absorption at optical wavelengths (red). This indicates that a massive halo of gas surrounds the galaxy. The optical data are from the Keck I Telescope at the W.M. Keck Observatory. Credit: ALMA (ESO/NAOJ/NRAO), M. Neeleman & J. Xavier Prochaska; Keck Observatory

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