Atlantis Links Up To Hubble For Repairs 132
An anonymous reader writes "Space Shuttle Atlantis has finally caught up with the Hubble Space Telescope after following it for several hours. The 'link up' between the Space Shuttle and Hubble was a very delicate one as the two were flying through space at 17,200 MPH, 300 miles above the Earth's surface. The robotic arm of the shuttle grappled the telescope at 1:14 PM EDT today. The telescope will be latched to a high-tech Lazy Susan device known as the Flight Support System for the duration of the servicing work."
How about Relative Speed? (Score:5, Insightful)
Why do these articles always tell us how difficult it was to do something in space because they are going so ridiculously fast? When taken relatively, they were practically sitting still while docking.
I know there are all kinds of other factors and I know it takes a lot of math to even get to the right orbit at the right time and speed to even see the Hubble, but after that, it ought to be relatively simple considering the lack of any unwanted or unexpected force on the crafts. I'm pretty sure it's much more difficult to land a jet on an air craft carrier, but I wouldn't know for sure.
17,000 mph (Score:3, Insightful)
Do people just look for big numbers to sound impressive??
The important number is the relative speed between Hubble and the shuttle. From my very precise calculation it was zero.
Re:Relative speeds (Score:4, Insightful)
I think you have it backwards. He understood that there is no actual fixed reference. He just meant that choosing the earth as a reference point didn't help one determine whether the linkage was difficult or not. Short answer: cut him some slack.
Delta-V, FTW!
-l
Re:Relative speeds (Score:3, Insightful)
No.. but one can "arbitrarily" select a fixed point as a reference.. as the parent poster stated.
"I arbitrarily choose the earth as the fixed point in the universe for all my velocity calculations."
See?
Re:Speed figures are meaningless (Score:4, Insightful)
You make it sound as if it was simple.
Of course, relative speed from the Shuttle to Hubbles is tiny.
But to match their relative speed from the ground is still pretty hard. Getting the shuttle from zero MPH to 17,000+MPH within inches of the Hubble so that their own relative speed nears zero for a dock is by all means, pretty neat stuff.
And for that, I go Oooh.
Re:17,000 mph (Score:5, Insightful)
Re:Speed figures are meaningless (Score:3, Insightful)
Well, the historical evidence confirms they're right, and you're wrong. Yes, you really do have to sit on top of enough propellent to push that massive shuttle straight up into the air and accelerate it to 17000 mph, with pinpoint precision. And sometimes, it blows up and everybody dies.
Re:impressive/not impressive (Score:3, Insightful)
"flying through space at 17,200 MPH, 300 miles above the Earth's surface. " Not impressive.
Then let's see you do it.
Give him 45 years, a multi-billion dollar budget, proven launch and flight platforms with 20+ years of successful flights, a number of catastrophic failures to learn from and a 50 odd professional test pilots and I'm sure he could do better than dock with a satellite in orbit.
NASA does more impressive stuff than this every day, and could be doing even more stuff if they were better managed and funded.
Re:impressive/not impressive (Score:5, Insightful)
Relative speed only meaningless in vacuum (Score:3, Insightful)
Under terrestrial conditions, there are all manner of random perturbations and ways that energy can couple into systems (i.e. make them smash) that flying high speed formation is tricky. It is even more serious at supersonic speed and that is why rocket staging is non-trivial and all the problems Space-X was having with rocket tests.
But in the vacuum of Earth orbital space, there is not much in the way of perturbations apart from the errant meteoroid, and flying formation is not big deal. Now getting the point of flying formation is a big deal as discovered by the Gemini crews on account of the Alice-in-Wonderland logic of orbital mechanics where thrusting forward (into a higher orbit) slows you down and retro thrusting (into a lower orbit) speed you up.
Re:Relative speeds (Score:2, Insightful)
No, your arbitrary choice does not make the point "fixed", even within the context of your calculation. It merely makes it a reference.
Re:Relative speeds (Score:3, Insightful)
Re:Obsolete Already? (Score:3, Insightful)
Because Hubble can do a number of important things that ground based scopes can't possibly do - like looking deep into the parts of the IR and UV bands that the atmosphere absorbs.
Well, no the new telescope doesn't have '100x the power' of Hubble. A telescopes power can't be measured on a single simple scale like a piece of gear in an RPG. The new telescope has 100x the light gathering area, but it still can't see the astronomical sources too faint for their light to penetrate the atmosphere. It'll have about 10x the resolving power of Hubble, but it's limited by atmospheric effects and the performance of it's adaptive optics.
Except if you actually follow the links and read the comments - you find that at best the Keck merely equals the performance of Hubble, it doesn't even remotely outclass it.