40 Years ago today

[a777pilot]

I take it that you're not aware of the James Webb Space Telescope. As long as funding doesn't get cut, it's supposed to be launched about 6 years from now. It's big enough to get the job done. For what it's worth, (and I've never verified this) but the Hubble isn't large enough to make out detail on the moon at a level where we could make out the stars and stripes on the flag planted there by the first Apollo astronauts to reach the moon. What I've read is that in order to be able to resolve to that scale, a telescope would need to be multiple kilometers across. If we built a Hubble like telescope with ten times the area, I'm not sure that it would really be that much of an improvement to make it worth it.

I did not know this. Thanks.

http://en.wikipedia.org/wiki/James_Webb_Space_Telescope

 

[Darwin333]

I take it that you're not aware of the James Webb Space Telescope. As long as funding doesn't get cut, it's supposed to be launched about 6 years from now. It's big enough to get the job done. For what it's worth, (and I've never verified this) but the Hubble isn't large enough to make out detail on the moon at a level where we could make out the stars and stripes on the flag planted there by the first Apollo astronauts to reach the moon. What I've read is that in order to be able to resolve to that scale, a telescope would need to be multiple kilometers across. If we built a Hubble like telescope with ten times the area, I'm not sure that it would really be that much of an improvement to make it worth it.

Could you help me out with the science here, I am not very well versed in optics. I always assumed that telescopes kind of scaled up so a telescope that was 10 times larger than the hubble could see 10 times farther which would indeed be a great thing. I am not all that interested in using it to look at the moon, its really close and we can send tons of satellites and robots there if we want to look at it. I want to see whats out "there" that we haven't already seen.

 

[ichy]

Could you help me out with the science here, I am not very well versed in optics. I always assumed that telescopes kind of scaled up so a telescope that was 10 times larger than the hubble could see 10 times farther which would indeed be a great thing.

It could collect ten times more light, that doesn't mean it can see ten times farther. I believe that larger telescopes also have higher angular resolution, but nowadays with interferometry you can get high angular resolution using multiple small telescopes rather than one large one.

 

[Brovane]

Some of the proposed Saturn V variants were insane. My favorite one used four liquid strap-on boosters that each had a pair of F-1 engines. That would've made for a total of 13 F-1s firing at launch. Obviously that kind of a booster was a space cadet fantasy but the idea was still cool, albeit absurd.

Re: a space station for telescope repairs, sadly it's just not worth the money or risk. No oribital observatory since Hubble has been designed for in-flight repair.

They did look at a lot of variants on the Saturn V
This page has a fairly good list - http://www.astronautix.com/fam/saturnv.htm

A lot of the designs where dictated by the 410 Maximum foot overhead crane height in the VAB.

The variant with the 13 F-1 engines was the Saturn V-23(L). It could put 262KG into a 185km orbit and lift 99,850 kg into a translunar trajectory. These where the strap on boosters, however they used F-1 engines with the J-2 engines in the 2nd and 3rd stages. The total height was 377 ft so it was doable.

The very Doable variant was the MLV-V-3 which was considered the ultimate for a improved Saturn-V. Had 5xF1A engines in the first stage and the J-2 where replaced with higher performing HG-3 engines. It could put 160,400kg into a 185km orbit and sent 65,800 kg into TLI. The TLI load was over 15 tons heavier than the baseline Saturn-V.
http://www.astronautix.com/lvs/satmlvv3.htm

This could have been a great heavy lift vehicle and basically all the technology as there in the late 60's to put it into production.

A interesting proposed variant was the Saturn V-B. It used a stage-half concept. You had 5 F-1 engines for the first stage. Once 70% of the fuel was burned 4 F-1 dropped away and the center engine would sustain the vehicle and could put 22,600 kg into LEO. The 4 F-1 engines that dropped away could then be recovered for re-use. This is very close to what the space shuttle does with similar re usability. They could have started worked on this in 1968 and probably by the early 70's had it rolling off the assembly line for very minimal cost. But no NASA and the Government wanted the shuttle.

 

[alzan]

You're behind the times. The answer was salt, molten salt to be exact.

http://news.cnet.com/8301-11386_3-57373508-76/solar-tower-will-power-las-vegas-at-night/

My bad. Thanks for the link.