Eta Carinae is one of the most massive and unusual stars in the Milky Way, and now NASA's Far Ultraviolet Spectroscopic Explorer satellite has detected a hot companion. This mysterious star, which scientists think is in the final stages of life, is located 7,500 light-years from Earth in the constellation Carina. Its companion star completes an orbit every 5.5 years, and FUSE was able to detect when it passed behind Eta Carinae, briefly dimming the amount of high-end ultraviolet radiation coming from the pair.

Scientists at the Lawrence Livermore National Laboratory have developed a detailed model of the Earth's climate over the next few centuries to answer the question... what if we burned all the fossil fuels by the year 2300. The answer, of course, isn't a pretty picture. In their model, global temperatures will rise 8-degrees Celsius (14.5 F), and melting polar caps will raise the oceans 7 metres (23 feet). The damage would be even worse in the polar regions, which could grow by 20-degrees C (68 F).

This photograph of Saturn's moon Dione was taken by Cassini on Sept. 20, 2005 from a distance of 2.1 million kilometers (1.3 million miles). The image shows the many canyons that crisscross the surface of the 1,126-kilometer (700-mile) moon, as well as its bright southern pole.

Time to revise your idea of Pluto. New images gathered by the Hubble Space Telescope have revealed that this distant planet could two additional moons. If this is true, Pluto will be the first Kuiper Belt Object found to have multiple moons. The candidate moons have been provisionally named S/2005 P1 and S/2005 P2, and are approximately 44,000 km (27,000 miles) away from Pluto.

Is science fiction an arena where fantasies run wild or an experimental lab where new technologies, cultures and even physics can be assessed? Afficionados of this genre more likely think the latter. But not long ago, science fiction stories and even rocketry were considered little more than a fool's occupation. One person bucked this trend. He is Jack Parsons and he is also the central figure in George Pendle's biography entitled Strange Angel. From this we read how Parsons made believers of many people who ridiculed science and space travel.

Greetings, fellow SkyWatchers! We begin the week on the eve of All Hallows as we learn the significance the Pleiades. Come... Join in the fun as we as the night steals our souls and gives us X-ray eyes. We'll search for glowing bones, watch fireballs, look into the eyes of a "Demon", brave a supernovae and stare down the "God of War". Go outside under the stars, if you dare. Because...

Here's what's up!

Things haven't gone well for the student-built SSETI Express, launched last week from the Plesetsk Cosmodrome on board a Russian Kosmos 3M launcher. Ground controllers haven't been able to make contact with the satellite since Friday, and a preliminary analysis points towards a failure of the satellite's electrical system. Controllers have a plan that might be able to restore power to the satellite, but it will take a few more days to know if it's going to work.

When you're exploring new territories, all kinds of things can go wrong. When you're exploring millions of kilometres away from Earth in an environment totally hostile to human life, these risks get deadly. NASA's Mars Exploration Program Analysis Group has put together a list of top risks for human Mars explorers, including the dust and potential biohazards. But one of the biggest risks is the lack of water - it's absolutely essential for a long-duration visit to the Red Planet.

NASA's Spitzer Space Telescope took this chilling image of the Black Widow Nebula for Halloween. In this image, there are two gigantic bubbles of gas being formed in opposite directions by the powerful outflows of newborn massive stars. These baby stars can be seen as yellow specs where the bubbles overlap.

Workers at the University of Arizona Steward Observatory Mirror Lab have cast the first mirror for the Giant Magellan Telescope. By the time they're complete, the lab will cast a total of 7 of these enormous 8.4-metre (27-foot) mirrors, giving the enormous observatory the equivalent of a 22-metre aperture. The Giant Magellan Telescope will be constructed in Northern Chile by 2016.

Look east this weekend and you'll see a bright red star blazing in the night sky. That's not a star, it's Mars, and on the night of October 29, it'll reach its closest approach. And you don't need dark skies, a telescope, or any special knowledge. Just look East... you can't miss it. Don't worry if you're too busy this weekend, Mars will stay bold and bright for the next few weeks.

One of the hazards of human spaceflight is the radiation damage of solar storms and cosmic rays. But it turns out the different parts of the human body are more susceptible to radiation than others. Although the best protection would be to get under cover, like in a spacecraft, future spacesuits could have extra radiation protection for specific areas of the body, like the hips (to prevent bone marrow damage).

A preliminary investigation by the Russian Failure Investigation State Commission has determined that a flight control system in the Rockot's Breeze upper stage caused the loss of the ESA's Cryosat satellite. The failure occurred when the Breeze didn't generate the command to shut down the second stage's engines. The Commission will present its detailed findings on November 3, 2005 to Eurorockot and the European Space Agency.

Geologists have come up with two measurements of radioactive decay to calculate when the Earth's core separated from its crust, but the problem is, these two numbers don't match. Researchers from the University of Bristol think that the giant collision that occurred early on in Earth's history - which went on to form the Moon - might have reset one of these "countdown clocks" and created the discrepancy.

A Russian Kosmos 3M launcher blasted off from the Plesetsk Cosmodrome this morning carrying a satellite designed and built by European university students. The Student Space Exploration and Technology Initiative (SSETI Express) satellite is about the size of a washing machine, and contains several detectors and experiments. Students working in 23 different university groups came together through the Internet to design and build the satellite.

This image is a mosaic of 15 photographs of Saturn's rings taken by Cassini. The strange ripples are caused by gravity from Saturn's moon Prometheus interacting with the ring particles. The ring particles closer to Prometheus move slower than the other particles, which gives the ring this ripple effect.

The massive Large Binocular Telescope, mounted atop Mount Graham in Arizona achieved a major milestone on October 12 with its first images - known as first light. The telescope is so powerful because it combines the light from its twin 8.4 metre mirrors to act as a single 11.8 metre observatory. And its adaptive optics system, which compensates for atmospheric disturbance, makes it even more powerful.

Eleven teams competed in two competitions over the weekend to test technologies for space elevators: beam-powered climbers and new ribbon materials. The climbers needed to scale a 61-metre (200 foot) ribbon within a time limit. Although one climber reached 12 metres (40 feet), it wasn't enough to win the $50,000 prize. In the ribbon competition, competitors needed to create a material that was 50% stronger than the house tether. One team came close, but it wasn't enough. Tougher challenges will be back next year with bigger prizes.

Venus Express was all set to launch, but ESA engineers discovered that small particles were contaminating the spacecraft, so the liftoff was pushed back. Engineers removed the spacecraft from its upper stage booster, opened up the fairing, and discovered that insulation material from the fairing had fallen onto the spacecraft. Fortunately, the pieces of material are large enough to see and remove with tweezers and vacuum cleaners. Once removal is complete, the spacecraft and booster will be reassembled and prepped for launch - before its launch window closes on November 24.

Greetings, fellow SkyWatchers... I'd once again like to express my thanks to the hundreds who took the time to write. This week we'll begin south as we have a look at the NGC 253. Mars isn't the only planet out there, but it's at its best! We'll have a look at planetary nebulae and discuss single stars - as well as try for a challenging comet and asteroid. So, head out under the stars...

Because here's what's up!