Posted on: Jun 28 2016, 12:32 PM | |
Member Group: Members Posts: 202 Joined: 9-September 08 Member No.: 4334 |
Wow - an ocean 45 kilometers deep, with the moon being 40% liquid water by volume? That's pretty incredible. |
Forum: Cassini general discussion and science results · Post Preview: #231384 · Replies: 10 · Views: 15463 |
Posted on: Jul 21 2015, 02:54 AM | |
Member Group: Members Posts: 202 Joined: 9-September 08 Member No.: 4334 |
I like seeing the real (well... closer to "real") colors. The Caribbean is incredible... the shallows there are almost emerald-colored. |
Forum: Earth Observations · Post Preview: #224313 · Replies: 174 · Views: 526479 |
Posted on: Dec 23 2014, 04:21 AM | |
Member Group: Members Posts: 202 Joined: 9-September 08 Member No.: 4334 |
Despite the result from the Hubble telescope, a check of old data by Cassini failed to reveal any plumes at Europa. That looks like it's only for one brief period (the flyby), though, right? So that doesn't really cast doubt on the Hubble results since it's not for the same time -- does it? |
Forum: Jupiter · Post Preview: #216562 · Replies: 131 · Views: 184089 |
Posted on: Nov 16 2014, 07:52 AM | |
Member Group: Members Posts: 202 Joined: 9-September 08 Member No.: 4334 |
So it's fluffy, but as hard as solid ice? Is it vacuum cemented together or something, or a thin layer of 'fluffy' on top of 'solid', I wonder? |
Forum: Rosetta · Post Preview: #215379 · Replies: 1412 · Views: 1147182 |
Posted on: Nov 11 2014, 08:11 AM | |
Member Group: Members Posts: 202 Joined: 9-September 08 Member No.: 4334 |
If you don't count the old communication satellite which used 2 lunar gravity assists to rescue itself and get back to a geostationary orbit. https://solarsystem.nasa.gov/news/display.cfm?News_ID=33835 Phil Ah, cool, I'd never heard of that - thanks. |
Forum: Private Missions · Post Preview: #214747 · Replies: 11 · Views: 27769 |
Posted on: Nov 10 2014, 12:18 AM | |
Member Group: Members Posts: 202 Joined: 9-September 08 Member No.: 4334 |
Is this the first private payload beyond LEO? |
Forum: Private Missions · Post Preview: #214713 · Replies: 11 · Views: 27769 |
Posted on: Sep 21 2014, 05:36 AM | |
Member Group: Members Posts: 202 Joined: 9-September 08 Member No.: 4334 |
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Forum: MSL · Post Preview: #213193 · Replies: 150 · Views: 157979 |
Posted on: Sep 12 2014, 05:23 AM | |
Member Group: Members Posts: 202 Joined: 9-September 08 Member No.: 4334 |
The difference between the daily high and low temperatures is huge! Looks like almost 80 degrees Celsius difference... (And why does the air pressure vary so much over the seasons? Is that because of CO2 freezing out of the atmosphere onto the polar cap in winter?) |
Forum: MSL · Post Preview: #212887 · Replies: 150 · Views: 157979 |
Posted on: Aug 27 2014, 03:47 AM | |
Member Group: Members Posts: 202 Joined: 9-September 08 Member No.: 4334 |
Without some kind of active solar panel cleaning, which we don't know how to do in a practical and flight-qualified way, there is simply no way to guarantee even two years of mission life on Mars without an RTG. The MERs got lucky with cleaning events. This is something I'd kind of wondered about... given that Spirit lasted dozens of times past the 90 day lifetime and Oppy is still going, in different locations, doesn't that move a bit beyond "got lucky" and into "Mars is a more benign environment for solar panels than previously assumed"? |
Forum: Tech, General and Imagery · Post Preview: #212392 · Replies: 13 · Views: 38788 |
Posted on: Jul 13 2014, 08:47 PM | |
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Congratulations! Awesome! |
Forum: Chit Chat · Post Preview: #211057 · Replies: 31 · Views: 23319 |
Posted on: Jul 2 2014, 02:11 AM | |
Member Group: Members Posts: 202 Joined: 9-September 08 Member No.: 4334 |
Just to let everyone know that we have found the required 2 faint KBOs in our pilot HST search program, and have been authorized to continue to the full 160-orbit Hubble search. We are all quite happy around here . Hubble news release John That's great! I hope something within New Horizons' delta-v range shows up (or even multiple objects to choose from?) EDIT: When will the full search be completed? |
Forum: New Horizons · Post Preview: #210803 · Replies: 574 · Views: 725239 |
Posted on: Jun 10 2014, 03:19 AM | |
Member Group: Members Posts: 202 Joined: 9-September 08 Member No.: 4334 |
Are these objects supposed to be too cold for WISE to have seen? IIRC WISE was supposed to have ruled out Saturn+ planets out to some huge distance... |
Forum: Telescopic Observations · Post Preview: #210204 · Replies: 72 · Views: 82045 |
Posted on: Jun 1 2014, 06:32 PM | |
Member Group: Members Posts: 202 Joined: 9-September 08 Member No.: 4334 |
Has anything more been said about the proposed late 2010s successor mission to Jupiter & the Trojan asteroids? Is that still planned? |
Forum: Private Missions · Post Preview: #210045 · Replies: 162 · Views: 202863 |
Posted on: Apr 23 2014, 01:33 AM | |
Member Group: Members Posts: 202 Joined: 9-September 08 Member No.: 4334 |
With that mass (3-10 Jupiter masses) and temperature, why is it called a "brown dwarf" at all? I thought that was above 13 Jupiter masses... is it because it didn't form in a protoplanetary disk? |
Forum: Telescopic Observations · Post Preview: #209184 · Replies: 133 · Views: 90137 |
Posted on: Apr 12 2014, 03:54 AM | |
Member Group: Members Posts: 202 Joined: 9-September 08 Member No.: 4334 |
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Forum: Venus Express · Post Preview: #208930 · Replies: 500 · Views: 609407 |
Posted on: Mar 22 2014, 05:40 PM | |
Member Group: Members Posts: 202 Joined: 9-September 08 Member No.: 4334 |
Interesting. But that seems only to relate to hydrogen abundances in minerals, not affecting the LCROSS results relating to polar ice in craters. |
Forum: Lunar Exploration · Post Preview: #208349 · Replies: 11 · Views: 21128 |
Posted on: Mar 21 2014, 11:51 PM | |
Member Group: Members Posts: 202 Joined: 9-September 08 Member No.: 4334 |
Ah - thank you again! |
Forum: Telescopic Observations · Post Preview: #208335 · Replies: 24 · Views: 26087 |
Posted on: Mar 21 2014, 05:57 AM | |
Member Group: Members Posts: 202 Joined: 9-September 08 Member No.: 4334 |
OK, thank you! So there is still thought to have been a Big Bang immediately before the inflationary epoch, rather than the inflation being a new model for the Big Bang itself? Is that correct? |
Forum: Telescopic Observations · Post Preview: #208311 · Replies: 24 · Views: 26087 |
Posted on: Mar 20 2014, 01:50 AM | |
Member Group: Members Posts: 202 Joined: 9-September 08 Member No.: 4334 |
Cool! (Now they just need to actually get one of the gravitational wave detectors to register one...) So this cosmic inflation thing... never been too clear on it... this is something that happened immediately after the Big Bang, rather than an alternative to Big Bang theory, right? One news article I saw about this was going on about multiverse stuff... is that related to inflation at all? |
Forum: Telescopic Observations · Post Preview: #208285 · Replies: 24 · Views: 26087 |
Posted on: Mar 16 2014, 06:26 AM | |
Member Group: Members Posts: 202 Joined: 9-September 08 Member No.: 4334 |
Because the ice crust may be recycled over reasonable scales of time, or a given spacecraft may hit the jackpot & impact a surface weak spot…stuff like that. Bottom line is that we really don't have a great handle on Europa's ice crust dynamics as yet, nor if there even really is an ocean underneath…too many unknowns. Therefore, the smart move is to be extremely cautious. Ah, OK, thanks... I just had seen stuff making it sound like it would be incredibly difficult to get through the ice intentionally (eg drilling lander) so it seemed like kind of a disconnect. When you say recycled over reasonable scales are you talking millions of years (short compared to the age of the moon itself) or something much shorter? |
Forum: Jupiter · Post Preview: #208214 · Replies: 107 · Views: 167015 |
Posted on: Mar 15 2014, 08:49 PM | |
Member Group: Members Posts: 202 Joined: 9-September 08 Member No.: 4334 |
I dunno if this is the right place for this... but what is the logic behind planetary protection for Europa? I had thought that the ice crust was at minimum 1 km thick... how could a reasonably sized spacecraft at orbital speeds possibly penetrate to an 'interesting' region? |
Forum: Jupiter · Post Preview: #208211 · Replies: 107 · Views: 167015 |
Posted on: Mar 14 2014, 01:43 AM | |
Member Group: Members Posts: 202 Joined: 9-September 08 Member No.: 4334 |
Ah... too bad. I was hoping "Tyche" would turn out to be real... |
Forum: Telescopic Observations · Post Preview: #208192 · Replies: 133 · Views: 90137 |
Posted on: Jan 11 2014, 05:56 AM | |
Member Group: Members Posts: 202 Joined: 9-September 08 Member No.: 4334 |
Well ... one hopes it will drop again as more information is added ... Not that 1 in 1000 is really that much of a risk. Especially since an object this size would have a good chance of harmlessly falling into/exploding over an ocean somewhere even if it DID hit. |
Forum: Cometary and Asteroid Missions · Post Preview: #206309 · Replies: 401 · Views: 362883 |
Posted on: Jan 11 2014, 05:53 AM | |
Member Group: Members Posts: 202 Joined: 9-September 08 Member No.: 4334 |
Awesome to see wetlands/lakes/etc. on another world... Also, Rev 200 - wow! |
Forum: Titan · Post Preview: #206308 · Replies: 9 · Views: 7986 |
Posted on: Dec 14 2013, 11:19 PM | |
Member Group: Members Posts: 202 Joined: 9-September 08 Member No.: 4334 |
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Forum: Chang'e program · Post Preview: #205533 · Replies: 305 · Views: 396097 |
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