New Mars Forums

http://www.msss.com/mars_images/moc/2003/05/22/]Earth and Jupiter as seen from Mars.

This came out last year, but I have not seen it posted here.

Would Jupiter's disk be viewable from the surface of Mars, and how large would it be compared to our full Moon in our skies?

From Earth the Sun appears about the same size as the Moon. Jupiter is about 1/10th the Diameter of the Sun, so, if you were to put Jupiter one AU from the Earth, it would appear 1/10th the Diameter of the Moon. At that distance, we would be able to see Jupiter’s disk.

At their closest approach, Mars and Jupiter get around 3.285 AU’s. Take our 1/10th Moon sized Jupiter and divide it by 3 and you get the size of Jupiter in Mars sky, during their closest approach. If I remember my math correctly, that would be 1/30 the Moon’s diameter.

For comparison, when Jupiter and Earth come as close as 3.951 AU’s. During this time, I calculate Jupiter’s disk is roughly 1/40th the full Moon’s diameter in our skies.

Someone with good eyesight might be able to see Jupiter’s disk from the surface of Mars, during their closest approach. Jupiter would be very bright on Mars.

BTW, Jupiter and Venus were very close together in Earth skies this morning. I think they'll be even closer tomorrow morning.

Good news, Cindy.

http://marsrovers.jpl.nasa.gov/gallery/ … 1.JPG]Here is another recent image from Opportunity. I find it a interesating picture.

http://marsrovers.jpl.nasa.gov/gallery/ … html]Looks like Opportunity is coming out of Endurance.

I suspect Opportunity will last longer than Spirit, considering it has not driven as far, or had as rough terrain to traverse.

I added each worlds mass to the chart. That makes it a little more interesting.

World..........Diameter (km)..  Gravity (G). .  Mass (kg)
Sun...............1,391,400........27.9.............1.99E+30
Jupiter..............142,800..........2.6431........1.90E+27
Saturn..............120,540..........1.1013........5.69E+26
Uranus...............51,118..........0.8799.........8.68E+25
Neptune…...........49,528..........1.1408.........1.02E+26
Earth.................12,756..........1.................5.98E+24
Venus................12,104..........0.9125..........4.88E+24
Mars...................6,787..........0.3821..........6.42E+23
Ganymede............5,262..........0.1542..........1.48E+23
Titan...................5,150..........0.1409..........1.35E+23
Mercury................4,878..........0.3924..........3.30E+23
Callisto.................4,800..........0.1206..........1.08E+23
Io........................3,630..........0.1802..........8.94E+22
Moon....................3,467..........0.1611..........7.35E+22
Europa..................3,130..........0.1435..........4.80E+22
Triton……….............2,700..........0.0607..........2.14E+22
Pluto.....................2,300..........0.0534..........1.29E+22
Titania..................1,580..........0.02..............3.50E+21
Rhea.....................1,530..........0.0281..........2.49E+21
Oberon..................1,520..........0.0106...........3.03E+21
Iapetus..................1,440..........0.0225..........1.88E+21
Charon...................1,190..........0.021...........1.90E+21
Umbriel……..............1,170..........0.0083..........1.27E+21
Ariel......................1,160..........0.0127..........1.27E+21
Dione.....................1,120..........0.0222..........1.05E+21
Tethys...................1,050..........0.0153..........7.55E+20
Ceres.......................914..........0.0441..........8.70E+20
Pallas.......................522..........0.0198..........3.18E+20
Vesta.......................500..........0.0201..........3.00E+20
Enceladus................500..........0.0079..........8.40E+19
Miranda...................470..........0.0042..........6.33E+19

Cindy, in reguards to Titan as a planet. Here are the stats of the top 30 worlds of our Solar System, ranked by size.

As you can see, Titan and Mars are close in size.

                      Size (km)      Surface gravity (g)
Sun                 1,391,400        27.9000
Jupiter                142,800         2.6431
Saturn                120,540         1.1013
Uranus                 51,118         0.8799
Neptune               49,528         1.1408
Earth                   12,756         1.0000
Venus                  12,104         0.9125
Mars                      6,787         0.3821
Ganymede (Jupiter)  5,262         0.1542
Titan (Saturn)         5,150         0.1409
Mercury                  4,878         0.3924
Callisto (Jupiter)       4,800         0.1206
Io (Jupiter)              3,630         0.1802
Moon (Earth)            3,467         0.1611
Europa (Jupiter)        3,130         0.1435
Triton (Neptune)       2,700         0.0607
Pluto                       2,300         0.0534
Titania (Uranus)        1,580         0.0200
Rhea (Saturn)           1,530         0.0281
Oberon (Uranus)        1,520         0.0106
Iapetus (Saturn)        1,440         0.0225
Charon (Pluto)           1,190         0.0210
Umbriel (Uranus)        1,170         0.0083
Ariel (Uranus)            1,160         0.0127
Dione (Saturn)           1,120         0.0222
Tethys (Saturn)         1,050         0.0153
Ceres 1 (Asteroid)         914         0.0441
Pallas 2 (Asteroid)         522         0.0198
Vesta 4 (Asteroid)         500         0.0201
Enceladus (Saturn)        500         0.0079
Miranda (Uranus)           470         0.0042

Using orbital tools, such as sun shades, lenses, and mirrors, humans will be able to control the climates of Earth, Venus and Mars. A solar shade that only let a percentage of Solar Radiation through it would help counter the effects of a warming sun.

I am working on a story about the end of the universe. In this story, most stars have burned out. The surviving races come up with several way to survive the darkening universe. Standard practice is to move yo0ur planet away from the dying star as it enters Red Giant phase and then move it back in as the star shrinks and cools. Eventually the race has to search for a new star, which are getting fewer, or find another way.

One way is to surround their planet in a shell that produces light. Hydrogen is their fuel they use to run this global light, and they scoop it off their frozen gas giant.

Another race has put ‘lights’ on it large moon so that it looks like a star and heats up their world.

Most other races tunnel into their world.

An aquatic race lives in a Europa like moon. This actually got me wondering if you could have a life zone in a Europa like ocean. Warm water is denser and it sinks, so wouldn’t the warm water stay close to the ocean bottom, creating a warm zone that covers the entire ocean floor? (Remember, you hear it from me first).

Our protagonist is in search of a fabled device that restarts stars. What it does is break down a star's atoms back into hydrogen and thus the star restarts itself. (You also heard that here first) Unfortunately, the people who guard this device are convinced stars are wasteful. They know how to convert matter 100% of matter to energy and they would prefer for stars to remain dark.

This has been a challenging piece to write. I hope to have it done in the near future.

Oppy has been slip sliding. Check out its rear wheels http://marsrovers.jpl.nasa.gov/gallery/ … M1.HTML]in this picture as Opportunity makes its way out of the crater.

Come on Opportunity. You can do it.

"I think I can, I think I can..."

http://marsrovers.jpl.nasa.gov/gallery/ … .HTML]Nice clouds!

Water on Titan would be like lava is here on Earth. I believe a water/ammonia mixture has lower freezing point so that might help water “lava” to stay liquid longer. Are there water volcanoes on Titan? Might be.

Methane, however can stay a liquid in Titan’s environment, and if those thunderstorms are raining methane, and it doesn’t evaporate soon after it falls, then there should be methane drainage channels.

http://photojournal.jpl.nasa.gov/jpeg/PIA06125.jpg]Look at the far right image in this set of three.

The south side of the dark feature sure looks like a shoreline. And those look like islands out in the dark feature. Is that a flooded crater I see in the dark area?

Great pictures, atompoid.

http://www.msss.com/moc_gallery/r10_r15 … 0.jpg]Here is one I have been looking over.

I find the dark streaks interesting. They must come from a sedimentary layer, but what are they composed of. Volcanic ash? Blueberries?

Even more interesting is the small crater at the very bottom of the image. If I am not mistaken, it has that “splashed” appearance that is formed when an impactor melts ice and splashes warm mud about. If this is the case, it must mean that groundwater/ice must be very close to the surface, which is surprising since this location is near the Equator.

Would a comet make a splash crater in a dry area?

Good one, Shaun.

And the Blueberries are really predators, and they were attacking the Giant Trilobite like Piranhas attack their prey.

Beware of the
http://images.amazon.com/images/P/B0000 … lueberries!