Humble Hubble

Atlantis on it's way to meet Hubble

Last week the final Hubble servicing mission was launched, which should keep the eye in the sky operating until 2014. The Hubble Space Telescope has been probing the murky depths of the universe for nearly 20 years, so a break is well deserved. In that time the orbital observer has made some pretty incredible discoveries that would never have been possible from Earth, what with all the pollution from the billions of street lights that interfere with ground-based telescopes. The service mission (STS-125), conducted by space shuttle Atlantis, should complete this Friday 22 May if everything goes to plan. On Saturday the amazing image above was captured of the shuttle flying in front of the sun. Meanwhile, here's some of the things Hubble has done for us (and some of the gorgeous images it's captured).

Ultra Deep Field

Ultra Deep Field

The Ultra Deep Field (above) is the deepest high resolution image ever taken in visible light and parts of the image are 13 billion light years away (i.e., galaxies as they were 400 to 800 million years after the Big Bang). The total exposure time for the image was just under one million seconds, taken over 400 orbits of the earth. Gathering an image of the entire sky at similar depth would take Hubble around a million years. Download the whole 6200 x 6200 pixel image here.

Eagle Nebula (Messier 16)

Hubble's Law

This one's pretty crucial - it theorises the age of the universe. In brief, it states that the speed at which galaxies are travelling away from us is related to their distance. From these rates of acceleration we are able to estimate both the age of the universe and thus the date of the Big Bang. Edwin Hubble first formulated this in 1929, but observations by the telescope that took his name have allowed the velocities involved to be measured in much greater detail. Also, it was previously predicted that the universe was decelerating under gravity, which we now know not to be the case.

Sombrero Nebula (Messier 104)

Dark Energy

This hypothetical form of energy potentially makes up nearly three quarters of the total mass-energy of the universe. Yet we know next to nothing about it, or even whether it really exists. Recent results from Hubble seem to show that dark energy has been around for at least nine billion years.

Messier 87 (thought to contain a supermassive black hole)

Black Holes

The theoretical concept of black holes has been around for around two hundred years - regions of space with gravity so powerful that nothing can escape them. Actually seeing them is pretty tricky since they don't emit any light or energy. It was Hubble that first saw direct evidence of them in 2001 by observing how UV light faded and disappeared as it swirled around the massive galaxy Cygnus XR-1.

Cat's Eye Nebula (NGC 6543)

Fun Fact: One of the crew members of the current service mission is part of an all-astronaut band back on Earth, called Max Q. Check them out. There was another band fronted by Michael Hutchence with the same name. Don't check them out.

All images courtesy of NASA