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OT: Spaceship One claims the $10 Million X-Prize!
Message #1 Posted by Gene on 4 Oct 2004, 11:18 a.m.

http://www.cnn.com/2004/TECH/space/10/04/spaceshipone.attempt.cnn/index.html

Congrat's! Now, on to Mars! :-)

      
Re: OT: Spaceship One claims the $10 Million X-Prize!
Message #2 Posted by Monte Dalrymple on 4 Oct 2004, 12:57 p.m.,
in response to message #1 by Gene

I was watching a documentary about this last night on the Discovery channel... and the aerodynamics guy was using an HP-48GX while sitting at his station monitoring one of the flights...

      
Re: OT: Spaceship One claims the $10 Million X-Prize!
Message #3 Posted by Thomas Cox on 5 Oct 2004, 7:24 p.m.,
in response to message #1 by Gene

Note that NASA has just announced that the "EDGE" of space is at 150 miles, so that as far as NASA is concerned Spaceship One reached only approximately half-way.

Sour-Grapes I think.

            
A new limit for space?
Message #4 Posted by Andrés C. Rodríguez (Argentina) on 5 Oct 2004, 8:36 p.m.,
in response to message #3 by Thomas Cox

Alan Shepard was the first american in space (Mercury was a NASA project, wasn't it?) reaching 115 miles in 1961. A 150 miles limit makes the Space Shuttle a not-so-spacial vehicle...

            
Re: OT: Spaceship One claims the $10 Million X-Prize!
Message #5 Posted by bill platt on 6 Oct 2004, 9:39 a.m.,
in response to message #3 by Thomas Cox

To me, the interesting thing to realize is that this business of "getting to space" (meaning merely going high up) is really not so terribly difficult today, relatively speaking. The fact is, there has simply not been a commercially viable reason to try before now--and that is the only real reason nobody tried to do this before the X-prize was introduced.

The real challenge is getting into orbit---and especially back again--and so by that measure, only the Soviet space programme and NASA can claim to be truly space-capable.

How fast did Spaceshipeone go relative to earth? 2800 MPH? (Maybe not even that fast, as they are powering during a significant portion of the climb, so the velocity to achieve altitude is less than that due merely to the gravitational acceleration vis-a-vis "exit velocity"). I'm not sure exactly, but that seems about right.

By contrast, to achieve orbit,, one needs to get up to approximately 18000 mph (depending on altitude). In terms of kinetic energy, that is 18000^2 / 2800^2 = 41 times more energy.

This is not to belittle Mr. Rutan's accomplishment--I am elated by the success.

"Scaled Composites" not only won the Ansari X-prize--they did it with real style, élan, poise.

The "ships" they built are beautiful. The approach so well thought out and thorough---I love the identical cockpits of the White Knight and the spaceship---even the names are good--White Knight looks like a knight with his jousting lance.

It will be interesting to see if Mr. Rutan and his team have a simple solution to the de-orbit problem capable of trumping the government-sponsored programs of the past.

Regards,

Bill

Edited: 6 Oct 2004, 9:49 a.m.

                  
Re: OT: Spaceship One claims the $10 Million X-Prize!
Message #6 Posted by Andrés C. Rodríguez (Argentina) on 6 Oct 2004, 12:49 p.m.,
in response to message #5 by bill platt

Bill:

I agree, "orbit" (and, BTW, de-orbit & reentry) is the name of the game. But, just as a minor conversation remark, Alan Shepard and Gus Grissom missions (Mercury capsule, Redstone rocket) were considered spacial enough by NASA in 1961, even when they were suborbital trajectories with a maximum of some 115 miles. After them, John Glenn (Mercury-Atlas) was the first US astronaut in orbit, not just in space.

                        
Re: OT: Spaceship One claims the $10 Million X-Prize!
Message #7 Posted by bill platt on 6 Oct 2004, 1:53 p.m.,
in response to message #6 by Andrés C. Rodríguez (Argentina)

Hi Andrés,

Yes, absolutely.

The trick is that the word "space' is very potent.

To really get a sense of perspective, a picture is just so much more powerful:

Draw a circle with a diameter of 6875 Nautical miles (approximately the diameter of the earth)

And then, draw a little parabola, sticking off of that big circle. Height of the parabola: 60 miles.

When you look at that picture, two things come to mind:

1. That is not a long trip 2. If that is space, then there isn't much "air" .

In fact, it really is not space, if you think of "space' as being outside the atmosphere---the most important layer of the so-called "Ionosphere"--the layer responsible for long-distance radio signals in the "shortwave" bands, is right at and above the 100 mile mark. (The "f" and "f2" layers). The "E" layer, which is responsible for extraordinary VHF propagation, is centered at about 60 miles--right where SpaceShipOne topped-out.

So, technically speaking, the trip to 60 miles high is a trip to the Ionosphere--not to space.

The space shuttle, when returning from orbit, is covered in plasma at this altitude, yes?

Best regards,

Bill


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