Updates Cassini Mission News and Updates

[GLS]

Saturn’s shepherd moon Daphnis makes waves

NASA’s Cassini spacecraft has captured the first close-up view of Daphnis, one of at least 62 moons found orbiting Saturn, plowing a path through the planet’s icy rings and raising waves in its wake.
The image taken by Cassini’s narrow-angle camera Jan. 16 is the best view ever taken of Daphnis, a football-shaped object carving a gap in one of Saturn’s outer rings. The spacecraft was about 17,000 miles (28,000 kilometers) from Daphnis at the time.

http://spaceflightnow.com/2017/01/19/saturns-shepherd-moon-daphnis-makes-waves/

 

[Nicholas Kang]

Close Views Show Saturn's Rings in Unprecedented Detail

Official NASA Press Statement:https://www.nasa.gov/feature/jpl/close-views-show-saturns-rings-in-unprecedented-detail

This Cassini image features a density wave in Saturn's A ring (at left) that lies around 134,500 km from Saturn. Density waves are accumulations of particles at certain distances from the planet. This feature is filled with clumpy perturbations, which researchers informally refer to as "straw." The wave itself is created by the gravity of the moons Janus and Epimetheus, which share the same orbit around Saturn. Elsewhere, the scene is dominated by "wakes" from a recent pass of the ring moon Pan.
Credits: NASA/JPL-Caltech/Space Science Institute

The views are some of the closest-ever images of the outer parts of the main rings, giving scientists an eagerly awaited opportunity to observe features with names like "straw" and "propellers." The new images resolve details as small as 0.3 miles (550 meters), which is on the scale of Earth's tallest buildings.

Cassini is now about halfway through its penultimate mission phase -- 20 orbits that dive past the outer edge of the main ring system. For now, the veteran spacecraft is shooting past the outer edges of the rings every week, gathering some of its best images of the rings and moons.

This image shows a region in Saturn's outer B ring. NASA's Cassini spacecraft viewed this area at a level of detail twice as high as it had ever been observed before.
Credits: NASA/JPL-Caltech/Space Science Institute

From this view of a region in the outer B ring, it is clear that there are still finer details to uncover.
Credits: NASA/JPL-Caltech/Space Science Institute

This image from NASA's Cassini mission shows a region in Saturn's A ring. The level of detail is twice as high as this part of the rings has ever been seen before. The view contains many small, bright blemishes due to cosmic rays and charged particle radiation near the planet.
Credits: NASA/JPL-Caltech/Space Science Institute

 

[Unstung]

JPL: "NASA's Cassini Mission Prepares for 'Grand Finale' at Saturn"

NASA's Cassini spacecraft, in orbit around Saturn since 2004, is about to begin the final chapter of its remarkable story. On Wednesday, April 26, the spacecraft will make the first in a series of dives through the 1,500-mile-wide (2,400-kilometer) gap between Saturn and its rings as part of the mission's grand finale.

"No spacecraft has ever gone through the unique region that we'll attempt to boldly cross 22 times," said Thomas Zurbuchen, associate administrator for the Science Mission Directorate at NASA Headquarters in Washington. "What we learn from Cassini's daring final orbits will further our understanding of how giant planets, and planetary systems everywhere, form and evolve. This is truly discovery in action to the very end."

[...]

The mission team hopes to gain powerful insights into the planet's internal structure and the origins of the rings, obtain the first-ever sampling of Saturn's atmosphere and particles coming from the main rings, and capture the closest-ever views of Saturn's clouds and inner rings. The team currently is making final checks on the list of commands the robotic probe will follow to carry out its science observations, called a sequence, as it begins the finale. That sequence is scheduled to be uploaded to the spacecraft on Tuesday, April 11.

Cassini will transition to its grand finale orbits, with a last close flyby of Saturn's giant moon Titan, on Saturday, April 22. As it has many times over the course of the mission, Titan's gravity will bend Cassini's flight path. Cassini's orbit then will shrink so that instead of making its closest approach to Saturn just outside the rings, it will begin passing between the planet and the inner edge of its rings.

"Based on our best models, we expect the gap to be clear of particles large enough to damage the spacecraft. But we're also being cautious by using our large antenna as a shield on the first pass, as we determine whether it's safe to expose the science instruments to that environment on future passes," said Earl Maize, Cassini project manager at JPL. "Certainly there are some unknowns, but that's one of the reasons we're doing this kind of daring exploration at the end of the mission."

[...]

---------- Post added at 12:38 AM ---------- Previous post was at 12:28 AM ----------

This is the ideal moonlet shape. You may not like it, but this is what peak shepherd looks like.

"Cassini Reveals Strange Shape of Saturn's Moon Pan"

 

[orb]

This is the ideal moonlet shape. You may not like it, but this is what peak shepherd looks like.

"Cassini Reveals Strange Shape of Saturn's Moon Pan"

Well, I like this shape, especially on pan.

Pan intended. :lol:

 

[SolarLiner]

So... That's it guys.

Cassini's low on fuel, and NASA is planning to make the probe do its final plunge into Saturn.

I'll definitely cry over the livestream they'll probably set up as Cassini give its last digital breath. That probe was launched before I was born, I followed it all throughout my life (yeah I know!), got me into everything astronomy and continue to fuel my passion for all time, basically.

Onto your Grand Finale, big boy.

 

[Artlav]

That probe was launched before I was born, I followed it all throughout my life

... now i feel old

But yes, i hope it would return some nice close-ups of the rings.

 

[Ravenous]

I'll definitely cry over the livestream they'll probably set up as Cassini give its last digital breath.

No tears from me - but CHEERS for the follow on. We need a proper sample of those geysers on Enceladus! :thumbup:

("The Enceladan Geezers" would be a great name for a crossover folk/space rock band.)

 

[Unstung]

NASA will discuss new results about ocean worlds in our solar system from the agency’s Cassini spacecraft and the Hubble Space Telescope during a news briefing 2 p.m. EDT on Thursday, April 13. The event, to be held at the James Webb Auditorium at NASA Headquarters in Washington, will include remote participation from experts across the country.

The Cassini data that will be discussed may be a couple years old since the spacecraft is currently perpendicular to the plane of the moons. The last Enceladus flyby was in 2015, but Saturn is surrounded by many other possible ocean worlds.

 

[Notebook]

http://www.bbc.co.uk/news/science-environment-39592059

Saturn's ice-crusted moon Enceladus may now be the single best place to go to look for life beyond Earth.
The assessment comes on the heels of new observations at the 500km-wide world made by the Cassini probe.
It has flown through and sampled the waters from a subsurface ocean that is being jetted into space.
Cassini’s chemistry analysis strongly suggests the Enceladean seafloor has hot fluid vents - places that on Earth are known to teem with life.
To be clear: the existence of such hydrothermal systems is not a guarantee that organisms are present on the little moon; its environment may still be sterile. But the new results make a compelling case to return to this world with more sophisticated instrumentation - technologies that can re-sample the ejected water for clear evidence that biology is also at play.

 

[Urwumpe]

I'll definitely cry over the livestream they'll probably set up as Cassini give its last digital breath. That probe was launched before I was born, I followed it all throughout my life (yeah I know!), got me into everything astronomy and continue to fuel my passion for all time, basically.

Yeah, I felt the same about Rosetta, after starting my career with it. But it ain't really sad tears.... you know it was about to happen, you know it was a full success. I think it is about like Patton said it: We shouldn't mourn probes that plunge into celestial bodies. We should feel proud that such missions had been done.

 

[RGClark]

So... That's it guys.
Cassini's low on fuel, and NASA is planning to make the probe do its final plunge into Saturn.
I'll definitely cry over the livestream they'll probably set up as Cassini give its last digital breath. That probe was launched before I was born, I followed it all throughout my life (yeah I know!), got me into everything astronomy and continue to fuel my passion for all time, basically.
Onto your Grand Finale, big boy.

Great sentiments. You summed up in a great way how many people feel about space.

Bob Clark

 

[Notebook]

Cassini probe sets up Saturn 'grand finale'
By Jonathan Amos
BBC Science Correspondent

Cassini is about to use a slingshot around Saturn's moon Titan to put it on a path towards destruction.
Saturday's flyby will sweep the probe into an orbit that takes it in between the planet's rings and its atmosphere.
This gap-run gives the satellite the chance finally to work out the length of a day on Saturn and also to figure out the age of its stunning rings.
But the manoeuvre means also that it cannot escape a fiery plunge into Saturn's clouds in September.
The US space agency (Nasa) is calling an end to 12 years of exploration and discovery at Saturn because the probe's propellant tanks are all but empty.

http://www.bbc.co.uk/news/science-environment-39672263

 

[Notebook]

http://www.esa.int/spaceinimages/Images/2017/04/Titan_flyby_22_April_2017

In the early hours of Saturday morning, the international Cassini–Huygens mission made its final close flyby of Saturn’s largest moon, Titan, coming within 1000 km of the atmosphere-clad world.
The image presented here is a raw image sent back to Earth yesterday, taken on Saturday at 18:42 GMT. It is one of many that can be found in the Cassini raw image archive.
The latest flyby used Titan’s gravity to slingshot Cassini into the final phase of its mission, setting it up for a series of 22 weekly ‘Grand Finale’ orbits that will see the spacecraft dive between Saturn’s inner rings and the outer atmosphere of the planet. The first of these ring plane dives occurs on Wednesday.

 

[K_Jameson]

The loss of Cassini will be a sad, sad moment. A truly exceptional mission and an intrepid spacecraft.

I wonder what will be my feelings when we will lose the contact with the Voyagers. The loss of Pioneer 10 had hurt me, at that time...
Let alone Galileo (I was a huge fan of that mission).

 

[Ravenous]

Heard an interesting comment on BBC radio this morning: Cassini will be doing its close Saturn approach backwards, so only the antenna gets struck if it meets any small fragments. (Important to mention the risk of this is apparently very low.)

Also there won't be any contact until Thursday morning, European time:

The earliest that Cassini is expected to report in and start downlinking new data is 07:05 GMT (08:05 BST) on Thursday.

http://www.bbc.co.uk/news/science-environment-39701671

 

[Artlav]

What happened to the "fly it through the Cassini gap" plan?

 

[Urwumpe]

What happened to the "fly it through the Cassini gap" plan?

Likely too far away from Saturn to do any research while also aiming at the end of mission with the last remaining fuel.

 

[Unstung]

Cassini is currently near its periapsis. Saturn must appear absolutely gigantic to an observer on the spacecraft. It will take 90 minutes for news of this event to reach Earth.

What happened to the "fly it through the Cassini gap" plan?

The spacecraft passed through the Cassini Division right after orbital insertion. Nope. Thought I heard that somewhere. Cassini pointed its antenna in its direction of motion after the burn as a precaution, however.

---------- Post added at 11:11 PM ---------- Previous post was at 02:11 AM ----------

Cassini started transmitting data back to Earth about an hour ago according to Eyes on the Solar System.

Cassini mission engineers are awaiting a signal from the spacecraft via NASA’s Deep Space Network, which is expected no earlier than around midnight PDT on April 26, 2017 (3 a.m. EDT on April 27, 2017).

https://saturn.jpl.nasa.gov/mission/grand-finale/milestones/

---------- Post added 04-27-17 at 12:04 AM ---------- Previous post was 04-26-17 at 11:11 PM ----------

[ame="https://twitter.com/CassiniSaturn/status/857488811508379650"]CassiniSaturn on Twitter: "Ground controllers have detected our carrier signal: Cassini is starting to phone home! Waiting for telemetry and spacecraft status¦ https://t.co/NntLBkHTMl"[/ame]

---------- Post added at 02:15 AM ---------- Previous post was at 12:04 AM ----------

JPL: "NASA Spacecraft Dives Between Saturn and Its Rings"

 

[Keatah]

I'm surprised we haven't heard from the chief imaging scientist Dr. C. Porco..? She's usually rather outspoken when it comes to Cassini imagery.

 

[Ravenous]

I'm surprised we haven't heard from the chief imaging scientist Dr. C. Porco..? She's usually rather outspoken when it comes to Cassini imagery.

Yeah it'd be interesting to see if they have any pics taken within the ring system. (Of course it may depend on the spacecraft attitude at the time.)