NASA Will Repair Hubble
31 Oct 2006 16:26:41 UTC
Topic 192006
(moderation:
When I learned of this a few minutes ago I couldn't resist bringing the news to the discussion board here. What wonderful news for "The People's Telescope."
CAPE CANAVERAL, Florida (AP) -- NASA Administrator Michael Griffin on Tuesday approved sending a space shuttle to repair the 16-year-old Hubble Space Telescope, reversing his predecessor's contentious decision to nix the mission.
"We are going to add a shuttle servicing mission to the Hubble Space Telescope to the shuttle's manifest to be flown before it retires," Griffin told workers at Goddard Space Flight Center in Maryland on Tuesday.
Griffin's announcement was greeted eagerly by astronomers who feared Hubble would deteriorate before the end of the decade without a mission to add new camera instruments, sensors and replace aging batteries.
The shuttle mission will likely be in early 2008.
Here's a link to the CNN story:
http://www.cnn.com/2006/TECH/space/10/31/hubble.ap/index.html
NASA Will Repair Hubble
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Adelante las naves!
Columbus
What's its odometer reading?
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What's its odometer reading?
I think Columbus used dead
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I think Columbus used dead reckoning as his navigatione method. See e.g:
Columbus
Tullio
RE: I think Columbus used
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I say there Magellan old chap, I was speaking of Edwin Hubble's outer space memorial telescope!
RE: RE: I think Columbus
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OK, sorry. But does it have an odometer?
RE: RE: RE: I think
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Tullio:
You've gotten me thinking. If one regards the solar system as a static device one simply adds up the mileage implied by its orbit by number of orbits plus a small amount accounting for launch. But, since its orbiting the earth as the earth orbits the sun the picture becomes more complex as you suggest. Moreover, are we talking about distance from where earth was in a cosmic co-ordinate system or where earth is now in that same co-ordinate system. Worse yet even is that the solar system itself has complex motion as a system within the milkyway which has its own degrees of motion amongst galaxies. Yes, does it have an odometer and how many?
RE: What's its odometer
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Good question, because it's much easier to imagine Hubble "circling overhead" rather than the intricate movements it makes throughout the solar system, miky way and so on, let’s see what the odometer reads relative to the Earth...
Deployed on April 25, 1990
Orbit is 575 km above the surface of the Earth
Orbits the Earth every 97 min.
Days in orbit - 6035 (four leap days)
Distance traveled in one orbit - 151 669 850 km
Total times orbited the Earth - 5 375 505
Obviously this is just an approximation, but it should be close..
The HST has traveled 315,302,037,024,250 km and counting.
Not to bad for something that looked like it was 'blind' once it was in orbit.
There are 10^11 stars in the galaxy. That used to be a huge number. But it's only a hundred billion. It's less than the national deficit! We used to call them astronomical numbers. Now we should call them economical numbers. - Richard Feynman
RE: RE: What's its
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I compared the numbers with that of Voyager 2, which is the most distant satellite with 12 *10^9 km. Your numbers just did not seem to fit...
Let's redo your math:
radius orbit: 575 km+6371 km=6946 km.
distance traveled per orbit: 2*pi*6946 km=43641.7 km
speed: 43641.7km /(97*60)s=7.5 km/s
6035 days=6035*24*60*60 s=521*10^6 s
distance traveled: 7.5 km/s * 521*10^6s=4*10^9 km
But still impressive!
Regards,
Bert
Somnio ergo sum
Our Sun, together with the
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Our Sun, together with the whole solar system, is orbiting the Galactic Center at a distance of ~26,000 light-years, on a nearly circular orbit. While the HST has been spiraling around the Earth, and the Earth around the Sun, the Sun's been moving at about 250 km/sec around the center of the galaxy. (It takes ~220 million years for the solar system to make one orbit, and it's done that 20-21 times in the last ~4.6 billion years, so the solar system is ~20 to 21 galaxy-years old... not sure what that is in dog-years...:)
So another 250 km/sec times 6,035 days is .... a bunch more kilometers to add to the odometer...
d = rt = (250 km/sec)(60 sec/min)(60 min/hr)(24 hr/day)(6035 days) = 130,356,000,000 kilometers, so...
adding the distance traveled in the solar system to the distance traveled through the galaxy, we have...
3,910,680,000 km + 130,356,000,000 km = 134,266,680,000 km which is ~1.34 x 10^11 kilometers...
Of course, the Milky Way is heading towards Andromeda, so some distance has been accumulated there as well...
Awesome news indeed, about a repair mission to the Hubble!
RE: Let's redo your
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This is another example of dead reckoning, as in Columbus days.
Tullio