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publiusr
2012-Jun-18, 05:52 PM
Fun Papers from arXiv - From 12 June 2012

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TELESCOPES

http://arxiv.org/abs/1206.1886 - Breakthrough capability for the NASA Astrophysics Explorer Program: Reaching the darkest sky

This space telescope proposal uses electric propulsion and a Mars flyby to reach a 15 degree inclined orbit. The idea is to get sufficiently off the ecliptic to avoid zodiacal glow.

I wonder how much it would take to convert one of those legacy NRO spysats into something similar. I seem to remember Delta III's and -IVs first satellites were mere test dummies. Perhaps Musk could be convinced to uses this as a test launch for Falcon 9 heavy. It might be able to do this all chemical.

antoniseb
2012-Jun-18, 07:03 PM
I moved this into its own thread from the Fun Papers thread.

antoniseb
2012-Jun-18, 07:07 PM
The overall idea is interesting... here's a few (surmountable?) obstacles

- You'd need a sponsor, NASA has no loose cash.
- You'd need to use a technology we haven't tried yet to handle the required data rate from that far away.

syzygy42
2012-Jun-18, 09:19 PM
- You'd need a sponsor, NASA has no loose cash.


Astronomy has had a history of private funding. Sometimes the funds came from the astronomer's own pocket (e.g., Lowell). But, I immediately thought of all of the effort that Hale went through to get funding to build telescopes. He got money from local business moguls, Yerkes & Hooker; from Carnegie, personally and through his institution; and the Rockefeller foundation.

With publiusr's mention of Musk, who else has $$ that they really can't spend and would like their name remembered more from a telescope than their business practices?

publiusr
2012-Jun-18, 10:39 PM
That's what I was thinking of. If Musk, Branson, etc has any cash--or could be persuaded by Universities with some help, then maybe the NRO gift is doable.

If there is anything that needs a dark sky, its this: http://wfirst.gsfc.nasa.gov/

Now according to Mr. Ellison here: http://www.bautforum.com/showthread.php/135140-I-Heard-A-Rumor-That-The-US-Military-Is-Gifting-NASA.../page2


NRO has not given NASA spacecraft. It's given it optical hardware. The top 'half' of a Hubble, if you will. The bottom half is the expensive half, the difficult half, the half that costs money and time to design build and test...The cost of turning a piece of optical hardware into an entire spacecraft is hugely expensive. Hundreds of millions of dollars. Moreover - it's HUGE. It's not mass that's the problem - it's volume - I doubt there's room as a secondary payload on a Falcon Heavy for it.


- You'd need to use a technology we haven't tried yet to handle the required data rate from that far away.

I didn't want to say it on that other thread so as to not provoke Mr. Ellison--but big volumes are what SLS LVs will have in spades--all the better for a nice big dish, similar to what was proposed here: http://www.nasa.gov/mission_pages/constellation/ares/space_telescopes_prt.htm
"One concept was for a 150-meter-wide (492 ft) radio telescope dish to detect whispers from deep space."
Now it doesn't need to be quite that large, but just having a big dish is helpful.

But the NRO gifts and SLS are two things that Mr. Ellison absolutely despises so I'll leave that alone.

Falcon Heavy might allow this to be its only payload, and since it is the optics alone, this presents Musk an opportunity to build the rest if some funding can be school-sourced instead of crowd sourced like this project that only needs 150 K
http://current.com/community/92837990_buythissatellite-150k-crowdfunding-project-to-provide-net-access-to-poor-countries-with-a-bankrupt-hi-cap-comsat.htm

This will be more expensive, true, but things change. The key is to be flexible, be open, and be calm. That only the optics are available may allow for longer term storage for other missions.

So the problem is distance, inclination, high volume--need for a big dish and the rather large optics which limits the choices of LVs to the larger end of the scale--thus the hostility:
http://www.parabolicarc.com/wp-content/uploads/2011/12/us_lvs_atoz.png

Huge optics are a burden only to those who want small LVs, but a boon to folks who know that large optics are exactly the big light buckets astronomers need.

Now there is something else to think about:

If person A is working at, say, JPL (and are used to getting a Discovery class mission every so often) let person B propose something a bit more challenging--that might threaten the funding of projects that person A is used to--watch as the fangs come out. We saw a bit of this with the hostility towards Curiosity on the part of MRO fans--so D.J wound up being on the other end of that one for a change, also unfairly.

What we really need is for more NASA funding to quelch the sniping.