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SLS / Orion / Beyond-LEO HSF - Constellation => Missions To Mars (HSF) => Topic started by: Star One on 02/09/2013 05:49 pm

Title: Telescope at Mars
Post by: Star One on 02/09/2013 05:49 pm
In this week's issue of the New Scientist it mentioned that one of the proposals put forward for the use of one of the two NRO telescopes gifted to NASA would be for it to put into orbit around Mars, either to survey Mars's surface or to look out at the universe from there.

How good an idea is this and how feasible would it be to launch such a no doubt large telescope out to Martian orbit?
Title: Re: Telescope at Mars
Post by: Archibald on 02/09/2013 06:02 pm
To look at the universe from Mars - can't see the point.
But to survey Mars surface ? why not ? after all they are first and foremost spy satellites... machines build to takes high resolution pictures of a planet surface.
With the Mars atmosphere much thinner than Earth, resolution can only be better.
Reminds me of that Lunar Mapping and Survey System - a KH-7 *hijacked* by NASA to map Apollo landing sites.
Title: Re: Telescope at Mars
Post by: Star One on 02/09/2013 07:40 pm
To look at the universe from Mars - can't see the point.
But to survey Mars surface ? why not ? after all they are first and foremost spy satellites... machines build to takes high resolution pictures of a planet surface.
With the Mars atmosphere much thinner than Earth, resolution can only be better.
Reminds me of that Lunar Mapping and Survey System - a KH-7 *hijacked* by NASA to map Apollo landing sites.


I have to agree that I cannot see what would be different about looking out at the universe from Mars compared to the Earth.
Title: Re: Telescope at Mars
Post by: Lee Jay on 02/09/2013 08:06 pm
Unless I've done my math wrong (someone please check me), the Rayleigh Criterion on this thing for 550nm light in a 235 mile orbit would be about 4 inches.
Title: Re: Telescope at Mars
Post by: Zed_Noir on 02/10/2013 01:21 am
Just one small detail. How are you going to transmit the data dump from an ex-NRO telescopes surveying Mars? Anyone got a guess to much bandwidth is needed per image frame taken with the telescope? Same question about data transmit  bottleneck also applied for astronomy usage.
Title: Re: Telescope at Mars
Post by: Lee Jay on 02/10/2013 02:05 am
Just one small detail. How are you going to transmit the data dump from an ex-NRO telescopes surveying Mars? Anyone got a guess to much bandwidth is needed per image frame taken with the telescope? Same question about data transmit  bottleneck also applied for astronomy usage.

Same way as with HiRISE.  Pick your spots.
Title: Re: Telescope at Mars
Post by: Dalhousie on 02/11/2013 09:19 pm
To look at the universe from Mars - can't see the point.

Longer baseline for measuring parallax has been suggested.  Possibly less influence from the zodiacal light.  Sun subtends a smaller part of the sky. If you go to radio astronomy, long baseline interferometry. 
Title: Re: Telescope at Mars
Post by: douglas100 on 02/11/2013 09:41 pm
Longer baseline for measuring parallax has been suggested.  Possibly less influence from the zodiacal light.  Sun subtends a smaller part of the sky. If you go to radio astronomy, long baseline interferometry. 

You can do long baseline work just as well in solar orbit. No need to go near Mars. Instead of using extra delta V to insert the telescope into Mars orbit, you could use the extra impulse to increase the aphelion of the solar orbit and enlarge your baseline.

Personally I think a Hubble type mission based at Earth-Sun L2 is a better option.
Title: Re: Telescope at Mars
Post by: Dalhousie on 02/11/2013 11:28 pm
You can do long baseline work just as well in solar orbit. No need to go near Mars. Instead of using extra delta V to insert the telescope into Mars orbit, you could use the extra impulse to increase the aphelion of the solar orbit and enlarge your baseline.

Quote
Personally I think a Hubble type mission based at Earth-Sun L2 is a better option.

It's called JWST ;-)
Title: Re: Telescope at Mars
Post by: IRobot on 02/12/2013 12:10 am
That idea is plain stupidity. You can have a very low orbit and achieve the same with a small telescope.

Take the money and spend it on small asteroid survey! There is a 50 meter rock shaving our atmosphere next Friday!

We don't need 2 more Hubble-class telescopes, right now we need two things:
- a large on-orbit telescope for exo-planet study (not discovery)
- a large number (tens of thousands) of small earth based telescopes (<1 meter diameter) scanning the sky for small asteroids, exo-planets, super novas and GRBs.

Actually all the sky can be scanned 100% of the time with some 100 telescopes spread across the globe, but turbulence and other weather conditions could prevent it.
Title: Re: Telescope at Mars
Post by: Russel on 02/12/2013 02:47 pm
I suspect this might have something to do with enabling a telescope at Mars.

http://www.nasa.gov/mission_pages/tdm/lcrd/lcrd_overview.html
Title: Re: Telescope at Mars
Post by: scienceguy on 02/13/2013 10:53 pm
You would get slightly better parallax measurements for star distances from Mars.
Title: Re: Telescope at Mars
Post by: IRobot on 02/13/2013 11:07 pm
You would get slightly better parallax measurements for star distances from Mars.
You could have the same without having to spend fuel to enter orbit on Mars...
Title: Re: Telescope at Mars
Post by: alexterrell on 02/14/2013 07:52 pm
Longer baseline for measuring parallax has been suggested.  Possibly less influence from the zodiacal light.  Sun subtends a smaller part of the sky. If you go to radio astronomy, long baseline interferometry. 

You can do long baseline work just as well in solar orbit. No need to go near Mars. Instead of using extra delta V to insert the telescope into Mars orbit, you could use the extra impulse to increase the aphelion of the solar orbit and enlarge your baseline.

Personally I think a Hubble type mission based at Earth-Sun L2 is a better option.
Solar orbit baseline inferometry would be great, but you'd need to design the telescopes from scratch.

If I understand it you need to know the separation of the telescopes to within less than a wavelength - so might be feasible with infra-red telescopes.

I've often wondered (OT here) what you could do with two 1km diameter radio telescopes in a 10AU solar orbit.
Title: Re: Telescope at Mars
Post by: happyflower on 02/21/2013 05:20 pm
In this week's issue of the New Scientist it mentioned that one of the proposals put forward for the use of one of the two NRO telescopes gifted to NASA would be for it to put into orbit around Mars, either to survey Mars's surface or to look out at the universe from there.

How good an idea is this and how feasible would it be to launch such a no doubt large telescope out to Martian orbit?

Will it be out of the realm of possibility to have one of these telescopes attached to some kind of propulsion (like a VASIMR or solar sails). It can then slow travel from one location to another and get some really detailed surface images of planets, moons, and asteroids?
Title: Re: Telescope at Mars
Post by: IRobot on 02/22/2013 12:40 am
Will it be out of the realm of possibility to have one of these telescopes attached to some kind of propulsion (like a VASIMR or solar sails). It can then slow travel from one location to another and get some really detailed surface images of planets, moons, and asteroids?
Why would you need sub-meter resolution of planets? That makes no sense! Telescopes don't need to be moved close, microscopes do.
Title: Re: Telescope at Mars
Post by: Lee Jay on 02/22/2013 12:58 am
Will it be out of the realm of possibility to have one of these telescopes attached to some kind of propulsion (like a VASIMR or solar sails). It can then slow travel from one location to another and get some really detailed surface images of planets, moons, and asteroids?
Why would you need sub-meter resolution of planets? That makes no sense! Telescopes don't need to be moved close, microscopes do.

We have telescopes and microscopes on Mars right now, capable of sub mm resolution, but only of a very small area.
Title: Re: Telescope at Mars
Post by: Dalhousie on 02/22/2013 01:00 am
Sub metre orbital imagery of planetary surfaces have revolutionised our understanding of the planets.  HiRISE, LROC and MOC for example. 
Title: Re: Telescope at Mars
Post by: happyflower on 02/22/2013 05:28 pm
Will it be out of the realm of possibility to have one of these telescopes attached to some kind of propulsion (like a VASIMR or solar sails). It can then slow travel from one location to another and get some really detailed surface images of planets, moons, and asteroids?
Why would you need sub-meter resolution of planets? That makes no sense! Telescopes don't need to be moved close, microscopes do.

For selfish reasons! There I said it.  :P

I can spend hours looking at the HiRISE images of Mars. Wouldn't it be cool if we had same kind of images from say Europa, Titan, Enceladus, Io, Ceres, or I dont know a few other places I cant remember? I'm not a scientist so not sure if useful, but I can imagine some beautiful images though.