Comments on: Dune Mars

By: Parrrrrrrre… iiiiiiiiii… doooooooliaaaaa! | Bad Astronomy | Discover Magazine

Fri, 26 Jun 2009 13:30:03 +0000

[...] in April, I posted an incredibly beautiful picture of sand dunes on Mars taken by the HIRISE camera. Here’s the [...]

By: Mars Reconnaissance Orbiter - Page 16 - Bad Astronomy and Universe Today Forum

Mars Reconnaissance Orbiter - Page 16 - Bad Astronomy and Universe Today Forum — Mon, 20 Apr 2009 18:35:36 +0000

[...] What do you think that would look like? I bet it would appear to be something like this: [...] Dune Mars in the BA’s [...]

By: Dunas de arena Barchan en Marte | Imagen astronomía diaria - Observatorio

Dunas de arena Barchan en Marte | Imagen astronomía diaria - Observatorio — Mon, 20 Apr 2009 06:00:05 +0000

[...] y se evaporan rápidamente en la delgada atmósfera de Marte, los persistentes vientos pueden hacer parecer a las grandes dunas de arena fluir e incluso gotear como un [...]

By: Tom Marking

Tom Marking — Wed, 15 Apr 2009 17:43:11 +0000

@paul “Human explorers have one infinite advantage over probes- on the spot intuition and reaction. Any robotic explorer will always be constrained by their rigid programing and a minimal 20 minute lag between itself and controllers.”

Mars came within 55,758,000 km of Earth on August 27, 2003. Light would have taken 3.1 minutes to go from Earth to Mars, and 6.2 minutes for a round-trip. So that’s considerably less than the “minimal 20 minute lag” being cited.

By: Tom Marking

Tom Marking — Wed, 15 Apr 2009 17:37:37 +0000

@Todd W. “Thanks for the numbers and the explanation as to why it would be that long.”

Click on my name for a link to a good web page which gives the derivation of these numbers. Over on the left side you want to select:

21b. Fly to Mars! (1)
21c. Fly to Mars! (2)
21d. Fly to Mars! (3)

They derive a wait time at Mars of 454 days which is approximately the same as the 14.9 months I calculated myself. So those links have all the details. Probably more than you wanted to know.

By: Todd W.

Todd W. — Wed, 15 Apr 2009 17:17:05 +0000

@Tom Marking

Thanks for the numbers and the explanation as to why it would be that long.

By: Tom Marking

Tom Marking — Wed, 15 Apr 2009 17:07:52 +0000

@Todd W “And talking about a year-long sit on the planet is jumping the gun a bit, dontcha think? Any manned mission would probably be only a few days at most for the first bunch of missions. Year-long stints would be quite a ways off.”

The first manned missions to Mars will be constrained by fuel efficiency are are likely to use Hohmann transfer orbits. In such a mission the total time is 30.67 to 33.19 months with a waiting time at Mars of 14.91 months. The 15-month delay at Mars is needed for the proper realignment of the Earth-versus-Mars position to occur. Thus, a more than 1 year wait at Mars is to be expected for the first Mars mission. How much of that time is spent on the surface of Mars is anyone’s guess.