M81 in Three Bands
Atlantis lifted off at 7:38 PM EST on a planned 11-day mission. These are old spacecraft, which makes one concerned for the crew's safety. Like the 1960's families who gathered around the TV set for every launch, we will ignore the media's fixation on suicide bombing heiresses and watch 7 people try to make a difference. I will delay my announcement about spaceflight until after they have returned safely.
A shuttle has many thousands of parts, any one of which could fail. The engines are pressurised via 24 spherical tanks filled with helium or nitrogen. The tanks are made of metal wrapped in kevlar, and must contain pressures up to 4600 psi. Failure of one of the tanks would be catastrophic. In 1988 the tanks were certified for an additional 10 years use. Since then the tanks' manufacturer has gone out of business. Two more flights to go for Atlantis, whose last flight will be the Hubble servicing mission scheduled for September 10, 2008.
One more three-colour picture for the week. Galaxy M81 in Ursa Major seen in infrared by the Spitzer Space Telescope (red), in visible light by Hubble (white) and in ultraviolet by the Galaxy Evolution Explorer. The youngest stars, seen in blue, line the galaxy's edges while older stars cluster near the centre. Interstellar dust appears in red. Hidden even from these eyes is a halo of "dark" mass, detectable only by its gravitational influence.
At the centre of this and every other galaxy is a supermassive Black Hole. Singularities were formed from quantum fluctuations shortly after the Big Bang. Giant Black Holes formed the seeds of clusters, galaxies and even smaller structures. Smaller Black Holes were attracted by the big ones and formed haloes around the galaxies. The matter we see is only a fraction of what is out there.
Check out the new Carnival of Space!
UPDATE: As this is published, a 3.5 inch hole has been found in Atlantis' thermal blanket. The fault has been judged to be non-critical and the mission goes on.