Comments on: Earthrise

By: See you at Enceladus » Blog Archive » A Bit of Ego Stroking, and a Lot of Modesty

Thu, 22 Jun 2006 22:07:57 +0000

[…] First, via the Bad Astronomy Blog: […]

By: Troy

Troy — Wed, 21 Jun 2006 22:42:54 +0000

I’ve always thought that 1% of pictures from spacecraft should be dedicated to capturing the asthetics of that unique environment. I’m not certain but I believe Galileo (spacecraft) could have imaged Amalthea as it did a final pass during its deorbit around Jupiter and no attempt was made because of a NASA policy that all images must be scientificly analyzed and that would have taken money which wasn’t originally allocated for the dying spacecraft.
The Voyager image of the solar system was pure genius. It had no scientific merit, but it is one of my favorites.
Regarding the Buzz Parsec question on how much easier Jupiter’s satellites would be, I did a check with Redshift which allows you to do astronomy from the surfaces of other planets. When Jupiter is at opposition Ganymede’s magnitude would be 4.56 with Jupiter approximately 3.85 a.u. away. Compare this to Earth where Ganymede would be 4.83 magnitude. There is a significant difference but I think it would still be too dim to see. On the other hand Earth’s moon would be quite visible so perhaps heliocentrism would have been an easier bite to swallow. Of course even when people are shown proof there can still be resistance to new ideas.

By: Robert Carnegie

Robert Carnegie — Wed, 21 Jun 2006 21:07:25 +0000

There’s a touching episode in C. S. Lewis’s _Out of the Silent Planet_, a sort of theological science fiction story. An Earthman stranded on another planet (Bad Astronomy: Martian canals) runs into an alien astronomer, who forms the opinion that the refugee’s home planet is Thulcandra, an ill-favoured place in their astronomy and their religion - and it is; he sees a small but detailed spot in a mysterious telescope, recognisable but rather sadly upside down. He is deeply saddened.

Joe: my MSIE says that https www.planetary.org/bluedot_poster.html has a wonky security certificate, so I don’t think I want to go. But it sounds lovely.

By: icemith

icemith — Wed, 21 Jun 2006 17:09:24 +0000

Grrrrr. …Flashes OF light… in first para. ( I missed that typo. and a couple of minor ones).

Ivan

By: icemith

icemith — Wed, 21 Jun 2006 17:03:00 +0000

I too noticed the spurious flashes if light in separated frames. One appears at , it seems, 90 degree orbital intervals. Obviously not the moon as it takes 28 days to cover full orbit. It does ‘orbit’ in the right curves, but the few sample shots would be far too few to define that orbit anyway. It is only a 29 minute window of the scene, so the orbital movement of the Moon in that time is negligible.

Linking to JPL’s Simulator and adjusting the various options, shows the Moon is close to the Earth from the viewpoint of Mars, and true, it must be in the general direction of the Sun. However, the Sun at that distance would not present as much glare as it would from Earth. But there may be a problem if the Moon is on the nearer side of Earth to Mars, the disk of the Moon would hardly be visible as it would be the dark side.

One thing I could not determine though, was the time exactly that corresponded to the 04:25 hours, ‘local time’ that the exposures started. Does it refer to the Mars time, GMT or US Eastern Standard? And how does one convert it anyhow? But I did notice though that plugging in ANY time for that day in Dec. 2005, gave little difference.

Ivan

By: Piles Of Rock

Piles Of Rock — Wed, 21 Jun 2006 16:06:54 +0000

Astronomy is cool…

Happy summer solstice everyone! The days only get shorter from here on out. Check out this picture of the Earth rising over Mars, like the Apollo pictures of the Earth rising over the moon, it really gives you a sense……

By: Tom

Tom — Wed, 21 Jun 2006 15:41:44 +0000

I ran a sim on Starry Night. Mars’ moons were well out of sight of this image. Looks like it was just two coincident ‘blips’