Just last week we talked about getting data back from Pluto from the New Horizons spacecraft.
Today NASA's "Dawn" spacecraft has returned the sharpest-ever photos of Ceres, just a month before its planned orbit around the mysterious dwarf planet.
On the night of March 5, Dawn will become the first spacecraft ever to orbit Ceres. Its the second solar system body (beyond Earth) that the Dawn space craft has orbited. (Dawn orbited the protoplanet Vesta, the asteroid belt's second-largest denizen, from July 2011 through September 2012.)
Space.com has a story and an animation built of multiple stills taken last Wednesday from 90,000 miles (145,000 kilometers) away from Ceres.
According to Dawn mission director and chief engineer Marc Rayman:
Despite Ceres' proximity (relative to other dwarf planets such as Pluto and Eris, anyway), scientists don't know much about the rocky world. But they think it contains a great deal of water, mostly in the form of ice. Indeed, Ceres may be about 30 percent water by mass.
Ceres could even harbor lakes or oceans of liquid water beneath its frigid surface. Furthermore, in early 2014, researchers analyzing data gathered by Europe's Herschel Space Observatory announced that they had spotted a tiny plume of water vapor emanating from Ceres. The detection raised the possibility that internal heat drives cryovolcanism on the dwarf planet, as it does on Saturn's moon's Enceladus. (It's also possible that the "geyser" was caused by a meteorite impact, which exposed subsurface ice that quickly sublimated into space, researchers said).
Its going to be an interesting couple months for space watchers.
Related Stories
Emily Lakdawalla's blog on The Planetary Society has an article on the details of communicating with New Horizons.
Pluto is far away—very far away, more than 30 times Earth's distance from the Sun — so New Horizons' radio signal is weak. Weak signal means low data rates: at the moment, New Horizons can transmit at most 1 kilobit per second. (Note that spacecraft communications are typically measured in bits, not bytes; 1 kilobit is only 125 bytes.) Even at these low data rates, only the Deep Space Network's very largest, 70-meter dishes can detect New Horizons' faint signal.
The article goes into some of the tricks used to improve the data rates and keep within the spacecraft power budgets.
NASA's Dawn Mission to Asteroid Belt Comes to End
NASA's Dawn spacecraft has gone silent, ending a historic mission that studied time capsules from the solar system's earliest chapter.
Dawn missed scheduled communications sessions with NASA's Deep Space Network on Wednesday, Oct. 31, and Thursday, Nov. 1. After the flight team eliminated other possible causes for the missed communications, mission managers concluded that the spacecraft finally ran out of hydrazine, the fuel that enables the spacecraft to control its pointing. Dawn can no longer keep its antennae trained on Earth to communicate with mission control or turn its solar panels to the Sun to recharge.
The Dawn spacecraft launched 11 years ago to visit the two largest objects in the main asteroid belt. Currently, it's in orbit around the dwarf planet Ceres, where it will remain for decades.
Also at Ars Technica, The Verge, and Science News.
Previously: NASA's Dawn Spacecraft Nears the End of its Mission
NASA Retires the Kepler Space Telescope after It Runs Out of Hydrazine
Related:
Pluto and Ceres
After Eight Years, NASA's Dawn Probe Brings Dwarf Planet Ceres Into Closest Focus
NASA's Dawn Orbiter Finds a Mountain on Ceres
Dawn Spies Magnesium Sulphate and Possible Geological Activity on Ceres
Ceres' Cryovolcano Ahuna Mons Formed in the Geologically Recent Past
Ceres's Cryovolcanoes Viscously Relax Into Nothingness
Organic Molecules Found on Ceres
Early Asteroids May Have Been Made of Mud Rather Than Rock
Dawn Mission Extended at Ceres
Ceres May Have Had a Global Surface Ocean in the Past
Bright Areas on Ceres Suggest Geologic Activity
Dawn's Orbit Around Ceres: A New Low
Dawn's Orbit Around Ceres: First Images
Dawn Spacecraft Captures Closest-Ever Images of Ceres' Shiny Occator Crater
(Score: 0, Funny) by Anonymous Coward on Saturday February 07 2015, @01:25PM
Massive rocky Pluto sodomizing Ceres up her frigid anus. That's no dwarf planet!
(Score: 0) by Anonymous Coward on Saturday February 07 2015, @04:54PM
Where is Uranus in this joke?
(Score: 2) by wonkey_monkey on Saturday February 07 2015, @03:58PM
Today NASA's "Dawn" spacecraft has returned the sharpest-ever photos of Ceres [...]the mysterious dwarf planet.
Dawn orbited the protoplanet Vesta [...] from July 2011 through September 2012.
What makes Ceres a dwarf planet, but Vesta a protoplanet? Or is somebody just bandying around cool-sounding astrobabble?
systemd is Roko's Basilisk
(Score: 3, Informative) by aristarchus on Saturday February 07 2015, @07:38PM
What makes Ceres a dwarf planet, but Vesta a protoplanet?
Basically, a dwarf planet must have enough mass to be able to form a spherical shape. Ceres does, Vesta is kind of, um, lumpy.
(Score: 3, Informative) by Gravis on Saturday February 07 2015, @04:25PM
please test that links in the story work before publishing because the first link is busted.
(Score: 2) by frojack on Saturday February 07 2015, @06:25PM
Ouch, My Bad....
The proper link is https://soylentnews.org/article.pl?sid=15/02/02/224222 [soylentnews.org]
No, you are mistaken. I've always had this sig.
(Score: 0) by Anonymous Coward on Sunday February 08 2015, @12:39AM
My Bad
I don't think so.
This has been an ongoing problem.
I thought it was slated to be fixed in the recent Slashcode update.
Apparently, if the link in the summary is to soylentnews.org and it contains an ampersand, it gets munged.
-- gewg_
(Score: 2) by martyb on Sunday February 08 2015, @01:58PM
Your submission was fine -- there's an issue in what editors see in our edit window, in what gets put in our preview window, and what gets written to disk. And, at the moment, it seems to only get buggered up when it is a link to a soylentnews story. (At least, that's how I understand it.) Plans are to have it fixed in the next site update.
Wit is intellect, dancing.
(Score: 2) by martyb on Sunday February 08 2015, @01:38PM
Sorry about that! There's a known bug with the Editor's controls which occasionally mangles Soylentnews links. We hope to have that fixed in the next release of the site code.
It should be correct, now. Thanks for pointing it out!
Wit is intellect, dancing.
(Score: 2) by FatPhil on Saturday February 07 2015, @05:30PM
According to wikipedia, it's mass is 9e20 kg, and the earth's surface area is 510072000 km^2.
Therefore the third of its mass that is water would be able to cover the entire planet to a depth of:
9e20/3/(510072000*1000^2)/1000 ~= 590 m
Of course it would run down the hills to the oceans, which means that the actual increase would be between 588 and 588/0.71 ~= 830m.
Great minds discuss ideas; average minds discuss events; small minds discuss people; the smallest discuss themselves
(Score: 3, Interesting) by frojack on Saturday February 07 2015, @06:47PM
Gently Landed....
If Ceres were to be deflected some how into an orbit close to that of Earth's its entirely possible that most of its water would be lost to evaporation over time, and much of it might have enough velocity to leave Ceres' weak gravity and turn to minute ice crystals in space.
Being so close to earth substantial portions might then be attracted to and accreted by earth as it sweeps through space. It would happen so slowly there would be no impact event, just rising seas.
After all, Physics Professor Louis A. Frank speculated [wikipedia.org] this is how much of Earth's water was accreted on earth over time and the process continues today.
It might be less exciting and more useful if we could divert Ceres to Mars.
No, you are mistaken. I've always had this sig.
(Score: 3, Interesting) by Foobar Bazbot on Saturday February 07 2015, @09:43PM
Of course, with Mars's smaller surface area you get about 2km deep.
But as spectacular a thought experiment as this is, I don't see a particularly logical reason to use Ceres for such an attempt -- it is after all only a third of the mass of the asteroid belt, so if you picked the most water-rich of the remainder, it seems like you could get the same water mass delivered while moving less rock mass...
(Score: 3, Interesting) by frojack on Sunday February 08 2015, @12:38AM
Assuming the lighter asteroids are composed of mostly water.... (Does anyone know? )
In any event, there is not enough sun heat at mars to melt these things so you would have to land them, so the smaller the better.
No, you are mistaken. I've always had this sig.
(Score: 0) by Anonymous Coward on Saturday February 07 2015, @09:49PM
http://m.xkcd.com/1476/#comic [xkcd.com]
-- gewg_