I agree completely. The technological benefits of returning to space are boundless. There is one intangible difficult to quantify—national pride in being THE country capable of providing much needed advances in technology and bringing forth the possibility of better living standards for the entire world. In my opinion, advances in medicine would be worth the effort. If we could eliminate 10 % of the waste and fraud in the Medicare and Medicade system we could finance NASA in a much more generous fashion.
I don't think any of NASA'a sensible and ultimately useful objectives in space require human presence. unless it's to provide material for press releases and "Discovery channel" documentaries. All of NASA's most impressive work - Hubble, Mars rovers, navigation satellites, apcae borne experiements - are carried out by unmanned craft via telemetry. Cheaper, safer, more productive. In terms of unmanned missions, NASA doesn't need to "return" to space. They are still up there.
@Battar: I agree with you that NASA doesn't need to "return" to space when they are already there. However, I disagree that a human presence in space is unnecessary. There is a lot of exploration that can be carried out by robotic probes, but human spaceflight is an important end in itself.
That being said, William Anders, the astronaut who took the iconic "Earthrise" photo, has said that we shouldn't travel to Mars until we're ready to do so as humans, rather than nationalistic Americans or Russians or Chinese or Indians.
I agree with that sentiment, although I'm not so sure about the possibly centuries-long wait it might impose.
you say that "Human spaceflight is an important end in itself".
What problems does it solve, what scientific or engineering objectives does it meet?
If it's an emotional ideal, it's just not worth the multi-billion dollar investment. Just to put things in perspective, NASA could sent 3 robotic probes to Mars for the price of a single shuttle mission.
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