| Page 17 of 23 |
[ 334 posts ] |
Deep Space Hardware (MARS)
| Author | Message |
|---|---|
|
Moon Mission Member ![]()
Joined: Fri Jan 09, 2004 11:52 am
Posts: 1267 Location: Exeter, Devon, England |
Richard
have you thought about the N-Prize at all? _________________ > http://www.fullmoonclothing.com > http://www.facebook.com/robsastrophotography > robgoldsmith@hotmail.co.uk |
| Back to top |
|
|
Space Station Member ![]()
Joined: Thu Jan 27, 2005 12:34 am
Posts: 450 |
I have seen references to the “N Prizeâ€
|
| Back to top |
|
|
Space Station Member ![]()
Joined: Thu Jan 27, 2005 12:34 am
Posts: 450 |
MARS Note: I have been estimating the power requirements for Mars Radio Transmission (including news Video for rebroadcast) using ordinary terrestrial assumptions. The very low noise temperature for a good antenna pointed at the sky makes the required power less than 1/10 that for terrestrial service! Adding the benefits from optimum modulation methods and excellent error correction brings the total improvement to over 100! Thus far less power will be needed for Mars transmissions than I originally expected, or transmission can be 100 times faster with the assumed power.
|
| Back to top |
|
|
Rocket Constructor ![]()
Joined: Tue Apr 22, 2008 5:21 pm
Posts: 5 |
Mr Speck,
I think you are corrct on you dismissal of balloon launch of most orbital vehicles, not for the stated reasons however. The advantages of launching a small solid rocket at a 10mBar atmospheric pressure are considerable. Here is one quick example: http://www.redyns.com/Reference/RockoonTrade.pdf The much lower ambiant pressure can gives a much better expansion ratio (isp) The lower pressure can give much lower tank pressures for pressure fed liquids. (mass fraction) The lower pressure/density will give lower aerodynamic loads, which make a large difference in high acceleration (small/solid) rockets with proportionally larger frontal areas. (drag losses) On the other hand..... I've launched a lot of scientific balloons, and for all but the very smallest vehicles, the ground handling and weather impacts make the thought of a slightly larger first stage (or a zeroth stage) look really good. Heck even an aircraft release makes some sense. For small vehicles, the DeltaV required for LEO can exceed escape velocity! see this chart: http://www.redyns.com/Reference/OrbitReq.gif From this paper: http://www.redyns.com/Reference/MinLaunchVehicle.pdf Maybe this paper makes many poor assumptions, but it is still interesting. -Gar |
| Back to top |
|
|
Rocket Constructor ![]()
Joined: Tue Apr 22, 2008 5:21 pm
Posts: 5 |
Seems like when I did the math, the path loss for Earth-Mars one way radio transmission near Conjunction (opposite side of the solar system) is approximately that of a Earth Based Moon bounce link.
Here is a link I just dug up to the old math: http://www.redyns.com/Projects/EMME.pdf So a viable Mars communication system is testable in you own back yard once a day ! interested ? -Gar. |
| Back to top |
|
|
Space Station Member ![]()
Joined: Thu Jan 27, 2005 12:34 am
Posts: 450 |
Yours is an interesting observation, and I will consider it.
The challenge on the Mars expedition was sending broadcast quality Video (preferably HDTV). The power requirements to send enough material to satisfy sponsors looked like a possible problem. The lower actual noise temperatures largely solve this problem. Raw communication: "Still Alive?" ... ... "Yup!" never looked like a problem in the inner solar system. |
| Back to top |
|
|
Rocket Constructor ![]()
Joined: Tue Apr 22, 2008 5:21 pm
Posts: 5 |
Mr Speck,
I guess it comes down to bit-rate or how *Often* you want to see HD quality clips. 'Live' transmissions are going to be delayed just because of C anyway. What frequencies were you thinking of ? What Bit Rate ? What Noise temp ? I use the classic from Kraus: http://www.redyns.com/Reference/SkyTemp.jpg Using some coding like Viterbi or turbo coding on xPSK? Just rather curious, don't wish to be to nosey/noisy. -Gar. |
| Back to top |
|
|
Space Station Member ![]()
Joined: Thu Jan 27, 2005 12:34 am
Posts: 450 |
Micro-Space continues to push development of the communications components needed for our GLXP Lander system AND ITS TEST PROTOTYPES!
Space “Pros†|
| Back to top |
|
|
Space Station Member ![]()
Joined: Thu Jan 27, 2005 12:34 am
Posts: 450 |
The difficulty in finding nearly $10 Million for a Falcon 1 launch (not to mention the unimpressive flight history of that vehicle) has caused Micro-Space and its partners to accelerate our plan to pursue an independent launch capability. To top everything else, the Falcon 1 has TOO LARGE a payload capability for our basic GLXP flight, let alone the reduced mass missions which now seem possible. As other GLXP teams are forced to reduce their systems mass to match the meager funding that can be raised, we expect to become a prime launch supplier for them. Our target price is $2 Million to place 400 pounds in LEO orbit. A small addition will deliver an appropriate fraction of that mass to the Moon, and save a team that complexity. As always, Micro-Space offers to sell priority options for such launch services – taking priority even over flights of our own lander – for customers willing to provide early cash flow and prepared to ramp up funding for the operational vehicle when that step becomes appropriate.
This actually ratchets down the Micro-Space funding challenge, for the launch vehicle development – starting with what we have already invested and accomplished – is much less than the nearly $10 Million Falcon 1! Ours is not, of course, a sophisticated “race car†|
| Back to top |
|
|
Rocket Constructor ![]()
Joined: Tue Apr 22, 2008 5:21 pm
Posts: 5 |
Lt Col Michael L. Wolfert when he was at Air Force Space Command, identified approximately seven hundred (700) unique customers for very small space launch services. There are private labs, government labs, schools, businesses, and even individuals who desire a small launch vehicle, It is probably just a matter of price !
|
| Back to top |
|
|
Space Station Member ![]()
Joined: Thu Jan 27, 2005 12:34 am
Posts: 450 |
Micro-Space recently submitted the following 10 NASA SBIR proposals. None are “naked conceptsâ€
|
| Back to top |
|
|
Space Station Member ![]()
Joined: Thu Jan 27, 2005 12:34 am
Posts: 450 |
The Micro-Space “Centrifugal Evaporatorâ€
|
| Back to top |
|
|
Space Station Member ![]()
Joined: Thu Jan 27, 2005 12:34 am
Posts: 450 |
NSF (the (US) National Science Foundation) has recently entered “Space Researchâ€
|
| Back to top |
|
|
Space Station Member ![]()
Joined: Thu Jan 27, 2005 12:34 am
Posts: 450 |
As promised earlier, I will discuss the Micro-Space SBIR (Small Business Innovative Research) proposals in this forum. I will discuss our C Proposal, “ Automatic Solar and Celestial Navigation on the Moon and Mars (O4.03-9181)â€
|
| Back to top |
|
|
Space Station Commander ![]()
Joined: Mon Oct 06, 2003 9:22 pm
Posts: 858 Location: New York, NY |
take a look at the star tracker technology, it's used mainly for attitude control on satellites now, but a similar sort of thing could probably give you the exact position on the moon when combined with a few other measurands (for dark side navigation).
_________________ Cornell 2010- Applied and Engineering Physics Software Developer Also, check out my fractals |
| Back to top |
|
|
|
Page 17 of 23 |
[ 334 posts ] |
Moderator: rpspeck
Who is online
Users browsing this forum: No registered users and 2 guests |




Gabitasoft Interactive. All Rights Reserved.