A new supercomputer has been installed at the Rochester Institute of Technology to simulate the interactions between black holes and the evolution of galaxies. Known as the gravitySimulator, this computer will run simulations that calculate the gravitational interactions between thousands of individual stars. It can achieve a top speed of 4 Teraflops (4 trillion floating point instructions a second), making it one of the top 100 supercomputers in the world.

The Sloan Digital Sky Survey (SDSS) is a comprehensive view of the night sky gathered by a dedicated 2.5 m telescope in New Mexico. Astronomers have used this vast database to make many discoveries about our Universe. And now it's going to have a sequel. SDSS II will be a new survey beginning in 2008, and consisting of three parts: a continued mapping of deep space to image distant galaxies and quasars; a detailed survey of our own Milky Way galaxy; and a study of supernovae, to try and help pin down the mysterious dark energy accelerating our Universe.

NASA's Cassini spacecraft has gotten a good look at Saturn's unusually shaped moon Hyperion. It has many fresh craters, giving it a spongy looking appearance. Scientists estimate that the moon is only 60% as dense as water, which means that much of its interior must be completely empty space. The images were gathered during a recent Hyperion flyby, when Cassini came within 168,000 km (104,000) of the moon.

During the Apollo era of spaceflight, many US spacecraft and vehicles were left on the Moon when the astronauts returned home. For the first time in more than 30 years, we'll get a chance to see them again when NASA's Lunar Reconnaissance Orbiter arrives at the Moon in 2008. It will be equipped with a camera capable of resolving the surface of the Moon down to half a metre (1.6 feet). Some of the larger structures on the Moon are 9 metres (30 feet) across, so they should be easy to spot by the orbiter.

When Deep Impact's impactor slammed into Comet Tempel 1 on July 4, 2005, it released a tremendous cloud of fine powdery material from the comet's nucleus. Scientists are still studying the volumes of data acquired by Deep Impact, but it appears this plume was much brighter than anyone had expected; its surface was more like talcum powder than sand. The crater was probably on the large side of what was being predicted: 50 - 250 metres (165 - 820 feet).

Greetings, fellow SkyWatchers! It will be busy skies this week as the Moon goes through a series of occultations for viewers around the world - be it a star, Jupiter or even a comet! We'll begin by exploring the "Butterfly Cluster" and work our way through some new lunar features as the week progresses. The dance of Venus and Mercury continues, so open your eyes to the skies, because...

Here's what's up!

Hacking sounds crass. It manifests images of short cuts, jobs poorly done and people most interested in just finishing, no matter what. In the computer industry, sometimes this perfectly portrays hackers. However, for an expert, a hack is the complete opposite. It's a beautiful, well thought resolution that uses minimal effort. Often only those in the know truly appreciate it. Robert and Barbara Thompson in their book, Astronomy Hacks compile tips and techniques for observing the night sky. Their methods seem simple, yet they include detail to show they are experts who are presenting hacks derived from years worth of knowledge.

The Japanese space agency JAXA announced the successful launch of the ASTRO-E2 X-ray satellite on Sunday. A Japanese-built M-5 rocket blasted off from the Uchinoura Space Center carrying the Astro-E2 into orbit. This satellite, renamed Suzuka, is a replacement for the Astro-E satellite, which was destroyed because of a launch failure in 2000. Once it's operational, Suzuka will help astronomers understand the evolution of galaxies and the supermassive black holes at their centres.

One of the instruments tuned into Deep Impact is NASA's Swift satellite, normally designed to detect and analyze gamma ray bursts. Swift has been watching the expanding debris cloud, and detected increasing numbers of X-rays every day. This has enabled scientists to accurately measure the total amount of material released. So far, it appears that several tens of thousands of tonnes of debris were blasted off the comet into space; enough to bury a football field under 9 metres (30 feet) of dust.

Of the 130 extrasolar planets discovered to date, most have been found using the radial velocity method, where a planet causes tiny changes to a star's velocity compared to the Earth. This back and forth motion changes the wavelength of the light from our perspective. Another method, the transit method, has turned up 6 planets so far, and should find many more in the coming years. It works by watching for a star to dim slightly on a regular basis as a planet passes in between us and the star.

There's a new rumour going around the Internet. Maybe an excited friend has sent an email about a once in a lifetime chance to see Mars. Mars is going to make its closest approach on October 30th, 2005, and look bigger and brighter than it has in two years. Unfortunately, the closest approach actually happened two years ago, in August 2003, when the Earth and Mars were closer than they had been for 50,000 years.

A new study by NASA and the Naval Research Institute has found that exhaust from the space shuttle can create high altitude clouds over Antarctica, just a few days after launch. Exhaust released at an altitude of 110 km (69 miles) can form Antarctic polar clouds in the mesosphere (the second highest layer of the atmosphere). Scientists originally discovered the connection when they noticed iron particles in clouds above Antarctica, and couldn't imagine a natural process that could put them into the high atmosphere.

An international team of astronomers have discovered a strange source of high energy gamma rays. The object is called LS5039, and it's known as a microquasar because of the kinds of radiation it generates. Microquasars are binary systems, where a regular star orbits a dead star, like a neutron star or black hole. Material streams from the regular star to the neutron star in such quantity that it starts to back up, like too much water going down a drain. What's unusual about LS5039 is that it's producing more high energy gamma rays than should be possible.

NASA has taken detailed measurements of global sea levels, and confirmed that they're rising. Not only that, the rate is increasing. During the last 50 years sea levels have risen .18 cm (.07 inches) a year, but during the last 12 years, that rate is .3 cm (.12 inches) a year. Part of this rise is due to the expansion of water as it warms up, and part of it is from increased ice cap and glacier melt. It's estimated that 100 million people around the world will be affected by a one-metre (3.3 foot) rise in sea levels.

With the safety concerns resolved, NASA has announced that they will begin the official countdown for STS-114; the space shuttle return to flight. The countdown begins on July 10 at 2200 UTC (6:00 pm EDT), which is 43 hours before liftoff. If all goes well, Discovery and its seven-member crew of astronauts will lift off at approximately 1951 UTC (3:51 pm EDT) on July 13. They will visit the International Space Station to deliver some supplies, and then test out a series of new procedures designed to improve the safety of the shuttle.

Bigger is better. When you're making a telescope, you want to construct the biggest mirror you can. The European consortium building the Extremely Large Telescope (ELT) - a monster observatory with a main mirror that will be between 50-100 metres - moved a step closer to building their telescope today by releasing the scientific case. If development moves forward, the ELT could begin construction within a few years, and be complete by 2015. Where Hubble can resolve objects 95 m (311 feet) apart on the Moon, the ELT could resolve objects 2 m (6.5 feet) apart.

As Deep Impact's impactor probe smashed into Comet Tempel 1 this week, every available observatory, on land and in space was watching to help gather as much science as possible from this $333 million mission. The Gemini North telescope, located on Hawaii's Mauna Kea successfully captured images, before and after the collision that clearly show the debris cloud moving off the comet. They also found evidence that rocky materials were exposed on the comet's surface.

From space and even on the surface, Mars just looks dry, reddish and rocky as far as the camera can see. But there's actually a pretty complex world of minerals under that surface layer of basalt. By studying the surface of Mars with Mars Global Surveyor and Mars Odyssey, NASA scientists have turned up very interesting surface features which hint at the hidden minerals underneath. This research is published in the latest edition of the Journal Nature.