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Virgin Semi-Galactic?

PostPosted: 11 Jun 2007, 09:08
by preiffer
The content in the latest news story has got me thinking.

70 miles, they say - where you can see for "1,000 miles in each direction". Now, look at the background of the image of the "spacecraft". How far do you think you can see in that? (hint: It's a LOT more than a 1,000 mile radius)

So, let's put it into a bit of context:

I jump out of planes at 4.5 miles up. Nice view, but not exactly space ;)
A 747 can cruise at 7.8 miles.
Concorde used to cruise at 11.3 miles. From there, you could see the "curvature of the earth" - but hardly "space".

Now, SATELLITES - well, they "cruise" at around 250 miles up.


Now, the view. New York to San Francisco is roughly 3,000 miles. Remember when you've seen those images of space and spacecraft, with half of the earth in the background? Well, you're not exactly going to see that - you won't even be able to see the across the USA.



My point? Well, this "space travel" thing is all very cool - but I fear a little over-hyped. After all, you don't even get to leave the atmosphere. [n]

PostPosted: 11 Jun 2007, 10:15
by Bean Counter
Originally posted by preiffer
After all, you don't even get to leave the atmosphere. [n]
Debatable. Space Shuttle makes "atmospheric interface" (the hot bit!) at about 70 miles, so long as it is not too close to the equator, and many people use this as a rule of thumb for the 'top' of the atmosphere. So in that sense at 75 miles up, they are in space. Or you could use the mesopause at 50-60 miles above which pressure is negligible. On the other hand, there is still some temperature at 90 miles, albeit it is damn cold!

Either way, I think they can get away with saying 75 miles us just in space, especially as they will experience weightlessness (one of the distinctions of going on a space trip I guess).

Your point about the views is quite right though - no blue marbles for these tourists.

PostPosted: 11 Jun 2007, 10:49
by MarkJ
Heard a review of this book on Simon Mayo last week and it all sounds very interesting - this is from the synopsis:

In 1960, Captain Joseph Kittinger fell to earth from the edge of space and survived. He stepped from the basket of a gigantic helium balloon into an appalling, hostile environment which, without the protection of a pressure suit, would have simultaneously frozen his body and boiled away his blood. And yet, it is the air that Kittinger fell through that makes our lives on earth possible. We not only live in the air, we live because of it. And air is about much more than just breathing

PostPosted: 11 Jun 2007, 11:40
by woggledog
http://en.wikipedia.org/wiki/Project_Excelsior

Apparently (I read elsewhere, there was no feeling of falling for some time due to lack of atmosphere)

PostPosted: 11 Jun 2007, 14:02
by Wolves27
It still looks bloody high to me...

I'm just waiting for the days when we get a space hotel a la 2001.

Cheers!

Dean