A new planetarium to be proud of

The world's newest planetarium opens to the public in London tomorrow. Skymania News got a special preview yesterday, one day after it was officially opened by the Queen. We can report that London once again has a star theatre it can be proud of, filling the void left by the closure by Madame Tussaud's of its own planetarium last year. The new planetarium is at Greenwich, the home of astronomy in London, and the centre of timekeeping in the world. It is part of a £15 million redevelopment of the historic Royal Observatory and is named the Peter Harrison Planetarium after one of Britain's richest men who donated £3million to the project. Sitting on the world's prime meridian - zero degrees longitude - it resembles a cone tilted at 51.5 degrees, the latitude of London, pointing towards the North Star. The bronze-clad cone is sliced at right angles to align with the celestial equator. Its shiny surface is designed to mirror the sky, day and night. Yesterday, on an unusually warm and sunny day in London, you could feel the heat as the slice created a powerful second sun. Inside we reclined in large and comfortable aircraft-style seats for a showing of the first 25-minute program that paying visitors will see (the Queen got just a seven-minute, cut down version). The Digistar 3 projector gave us a view of the Royal Observatory on its hilltop at sunset as the sky darkened and stars appeared. But within moments we were launched on a journey into space to look back on the Earth and journey to the Sun. A brief skim across the surface of our nearest star, watching flares and prominences leap into space and we were away again on a voyage deep into the universe. Digistar 3's computer-produced stars may lack the sharpness of the classic Zeiss dumb-bell-style projectors. But they allow a three-dimensional trip that sends stars speeding past you like an episode of Star Trek. Highlights included flights into the Orion Nebula and the Pillars of Creation in the Eagle Nebula, before we mingled with the countless stars of the globular cluster M13 in Hercules. Before long we were back in the solar system and touching down once more in Greenwich Park, just in time to catch the dawn chorus. It is an entertaining and educational show that is bound to appeal to kids and adults alike. Don't miss it if you're in London! You can find out more at the observatory's website. ©PAUL SUTHERLAND, Skymania.com • Skymania welcomes your comments on our stories! For more space reading, check out the Skymania stores in the USA and in the UK. They are powered by Amazon so you can buy with confidence.

Colliding stars spark new cosmic blast

Astronomers have had their first ever grandstand view of a dramatic collision between two stars. The 'cosmic car crash' created a new type of explosion that had not previously been recognised in the universe. Amazingly it happened 49 million years ago in a distant galaxy and light from the flare-up has only just reached the Earth. Californian astronomers detected the blast while using a telescope at Lick Observatory to search for suicide stars blowing themselves to pieces as supernovae. When they turned their telescope on a galaxy called Messier 85, in the constellation of Coma Berenices, they recorded an explosion that was not powerful enough for a supernova. However, it was also too bright to be an ordinary nova - a star that occasionally throws of a shell of hot gas in a thermo-nuclear eruption. It beame clear that the blast was probably caused by two ordinary stars smashing into each other. The event has been labelled M85OT2006-1. Team leader Professor Shrinivas Kulkarni, of the California Institute of Technology, had been speculating on possible new classes of cosmic explosion other than novae, supernovae and gamma-ray blasts. Astronomers mounted a major follow-up program of observations with giant telescopes in California, Hawaii and Chile. Colleague Dr Arne Rau said: "I was simply floored. In a short time we went from speculation to a real discovery. It was an exciting moment for me." The galaxy Messier 85 is mainly made up of old stars and the astronomers believe that the stellar victims were probably of similar mass to the sun. They also believe that a similar event was detected in the nearby Andromeda galaxy, Messier 31, more than a decade ago, but was poorly studied. Last year, we reported how astronomers had witnessed the start of a supernova explosion for the first time. Photo: This image of Messier 85 was taken by the 0.9-meter telescope at Kitt Peak. Credit: National Optical Astronomy Observatory/Association of Universities for Research in Astronomy/National Science Foundation. ©PAUL SUTHERLAND, Skymania.com • Skymania welcomes your comments on our stories! For more space reading, check out the Skymania stores in the USA and in the UK. They are powered by Amazon so you can buy with confidence.

Spirit digs up clue to life on Mars

A wonky wheel on a robot rover has uncovered exciting new evidence that life could once have existed on Mars. The broken wheel on Nasa's Spirit rover gouged out a deep trench in the martian dirt as it was dragged along. Scientists back at mission control were astonished to see a bright patch of soil uncovered. Analysis shows it is a concentrated deposit of silica that could only have formed in the presence of water. It provides overwhelming new evidence that ancient Mars was once a blue planet - a much wetter place where life may have formed. Professor Steve Squyres, who is chief investigator for Nasa's Mars rovers, said: "You could hear people gasp in astonishment. This is a remarkable discovery." Spirit and its sister probe Opportunity landed on opposite sides of Mars in January 2004 on what were planned to be 90-day missions. They are still trundling about the Red Planet after more than three years of operation. Spirit is being carried along by five wheels that are still working. Professor Squyres added: "The fact that we found something this new and different after nearly 1,200 days on Mars makes it even more remarkable. It makes you wonder what else is still out there." Spirit made the find while exploring a range of hills inside the 100-mile wide Gusev Crater. Spirit had previously found other indicators of water at the site long ago, such as patches of water-bearing, sulphur-rich soil, alteration of minerals and evidence of explosive volcanism. Albert Yen of Nasa's Jet Propulsion Laboratory, in California, said: "This is some of the best evidence Spirit has found for water at Gusev." Scientists say the silica could have formed from the interaction of martian soil with acid vapours produced by volcanic activity in the presence of water. It could also have come from water in a hot spring environment. But they say the latest discovery adds compelling new evidence for ancient conditions that might have been favourable for life. Earlier this month, Nasa revealed that an orbiting probe had found evidence that water ice is still widespread on Mars. And in March, Europe's Mars Express probe showed there is enough ice at the planet's south pole to cover it with an ocean 36ft deep. In December, Nasa said they had found signs that water still flows on the red planet. ©PAUL SUTHERLAND, Skymania.com • Skymania welcomes your comments on our stories! For more space reading, check out the Skymania stores in the USA and in the UK. They are powered by Amazon so you can buy with confidence.

Exploding comet wiped out tribes

An exploding comet wiped out Stone-Age tribes, mammoths and other creatures in North America, scientists believe. The huge blast happened when a three-mile-wide space rock entered the Earth's atmosphere over Canada nearly 13,000 years ago. Researchers have found debris from the blast spread across the Earth from California to as far away as Belgium. The buried clues include nanodiamonds, the rare element iridium and tiny balls of glass-like carbon formed in explosive conditions. At one site in Arizona, the layers of comet debris were found to be covering mammoths that were being carved up by Stone Age butchers. The scientists told the American Geophysical Union in Mexico that the exploding comet would have set off bush fires right across North America. They believe it could explain the disappearance of ancient tribe the Clovis people, plus giant beasts including mammoths and mastodons from the continent. It also explains why elephants - descendants of the mammoth - are today found in Africa and Asia but not America. In 1908 another, much smaller comet exploded over a remote part of Siberia. It flattened trees across 800 square miles around. An asteroid impact is believed to have wiped out the dinosaurs 65 million years ago. And last year, scientists reported the discovery of a crater beneath the Antarctic ice from an impact that wiped out nearly all life 250 million years ago. An asteroid zipped past the Earth in March, proving that Earth is still in danger from cosmic collisions. The photo is from an expedition to Tunguska in 1927, and shows trees flattened by the explosion 19 years earlier. ©PAUL SUTHERLAND, Skymania.com • Skymania welcomes your comments on our stories! For more space reading, check out the Skymania stores in the USA and in the UK. They are powered by Amazon so you can buy with confidence.

New waterworld is made of hot ice

European astronomers have discovered a real life waterworld - a planet made of hot ice, orbiting another star. The distant planet, which is four times as wide as Earth, is almost entirely made up of water. But that water is in a very different state to any known on Earth. Extremely high pressures mean the water must be solid. However this "frozen" water must also be hot because the planet lies just 2.5 million miles from its parent star. Scientists say the suituation is like that of carbon which can exist in solid form as both coal and diamonds. The discovery team, led by Michael Gillon, from Liege, Belgium, discovered the new planet from François-Xavier Bagnoud observatory at St-Luc in Switzerland. They watched it pass in front of a red dwarf star 30 light-years away from Earth called GJ 436. This transit allowed them to measure its size as similar to Neptune and to tell what it is made of. The new planet's surface temperature is expected to be at least 300C (600F) so that it has an atmosphere of steam. But inside, the water is crushed under intense pressure to a state unknown on Earth outside the laboratory. Dr Gillon said: "This discovery is an important step towards the detection and study of Earth-like planets." News of the discovery comes a month after reports that water had been detected in the atmosphere of another alien planet. That was followed by news of the first extrasolar planet that could be a rocky world like the Earth. Incidentally, the St-Luc observatory website shows this picture of Dr Gillon performing a rather unorthodox analysis of the transit using a bottle opener and with some famous Belgian beer at his side. The above photo of François-Xavier Bagnoud observatory is courtesy the University of Liege. ©PAUL SUTHERLAND, Skymania.com • Skymania welcomes your comments on our stories! For more space reading, check out the Skymania stores in the USA and in the UK. They are powered by Amazon so you can buy with confidence.

Revealed! Dark side of the universe

Space scientists have got their first decent glimpse of the dark side of the universe in a major scientific breakthrough revealed today. The Hubble space telescope photographed a ghostly ring revealing the presence of the elusive and invisible dark matter that astronomers have been hunting for decades. It was produced during an enormous head-on collison between two vast clusters of galaxies five billion light years away from Earth in the constellation of Pisces. An international team of astronomers pointed Hubble at the celestial crash site, labelled ZwCl0024+1652. The orbiting observatory took a stunning image of the colliding galaxies, using Hubble's Advanced Camera for Surveys which unfortunately stopped working in January. Since then, astronomers analysing the image traced out the ghostly blue ring, which is 2.6 million light-years wide. They say it is like the ripple from a stone thrown into a pond - but at first they thought it was a blemish in Hubble's photo. James Jee, of Johns Hopkins University, Baltimore, said: "I was annoyed when I saw the ring because I thought it was an artifact. I couldn't believe my result. But the more I tried to remove the ring, the more it showed up. It took more than a year to convince myself that the ring was real." He added: "This is the first time we have detected dark matter as having a unique structure that is different from the gas and galaxies in the cluster." Dark matter is usually completely invisible because it does not emit light or reflect it. But the ring revealed itself by distorting around it the light from clusters of galaxies lying much further away. This is another form of gravitational lensing that Hubble has recorded in previous images of galactic clusters. Astronomers reported indirect evidence of the existence of dark matter last year by studying another cluster of galaxies using Hubble and other telescopes and also by observing dwarf galaxies from the European Southern Observatory in Chile. And Hubble has even mapped out how it may be spread in the universe. Previously astronomers knew dark matter must exist because galaxies could be seen to be much "heavier" and have a more powerful gravitational pull than was possible for the total contents of stars and other visible objects inside them. It is a vital component of the cosmos. Astronomers estimate that 22 per cent of the universe is made up of dark matter and that stars and other visible material forms only four per cent! They are still searching for another constituent, the invisible, so-called dark energy that astonishingly is predicted to make up around three-quarters of the universe. The Hubble discovery will be reported next month in the Astrophysical Journal. Photo: Nasa, ESA, M.J. Jee and H. Ford (Johns Hopkins University) ©PAUL SUTHERLAND, Skymania.com • Skymania welcomes your comments on our stories! For more space reading, check out the Skymania stores in the USA and in the UK. They are powered by Amazon so you can buy with confidence.

Now Spitzer maps a windy world

More hot news, quite literally, from beyond the solar system as astronomers create the first map of a planet around another star. The planet is a gas giant so the map is really charting features in its cloudtops including one prominent hotspot. Don't hold your breath for anything resembling Google Mars or Google Moon. However, scientists believe the technique will one day allow them to map rocky worlds that resemble the Earth. The newly-mapped planet, a windy world labelled HD 189733b, lies 62 light-years away in the constellation of Vulpecula. Its study is another triumph for the Spitzer space telescope, which observes the sky with infrared eyes. Heather Knutson, of Harvard University, is lead author of a paper about the research which appears in Nature this week. She said: "We are getting our first good look at a completely alien world. We felt a little like Galileo must have felt when he first glimpsed Jupiter through the eyepiece of his telescope." Knutson's team were unable to see the planet's disk itself as it is too far away. However, they measured changes in its brightness as it rotated and this allowed them to plot a simple brightness map. Knutson said: "We can see the changes in brightness as features in the planet's atmosphere rotate into and out of view." The completed map is compiled from more than 250,000 separate measurements. It reveals a hot spot that is about twice the size of Jupiter's Great Red Spot but considerably hotter at a scorching 1,700 F. The planet is an incredibly windy place too. Co-author David Charbonneau, of the Harvard-Smithsonian Center for Astrophysics, said: "This planet has powerful jet streams. While Earth's jet stream blows at around 200 miles per hour, the jet stream on HD 189733b may blow as fast as 6,000 miles per hour." Like many so-called "hot Jupiters", the giant planet lies very close to its parent star, at a distance of only three million miles, and zips around it in a year lasting just 2.2 days. Spitzer can only map such large, hot worlds but astronomers believe a future observatory, the James Webb Space Telescope, will catch detail on Earth-like planets after it is launched in 2013. The top image is an artist's impression of the windy world in orbit around its star. The other shows a projection of the created map onto a sphere. Credit: Nasa/JPL-Caltech/Heather Knutson (CfA). ©PAUL SUTHERLAND, Skymania.com • For more space reading, check out the Skymania stores in the USA and in the UK. They are powered by Amazon so you can buy with confidence.

Glowing planet is really hot news

Space scientists have discovered the hottest planet ever identified in the galaxy. The world, which is slightly smaller than Saturn, is glowing red like a cigarette butt. Labelled HD 149026b, the planet radiates heat at an astonishing 3,700 Fahrenheit according to the Florida team who found it. They were unable to see it separately from its parent star in the constellation of Corona Borealis, the Northern Crown. However they were able to measure the dimming of the starlight when the planet disappeared behind it, using a heat-seeking infrared space telescope called Spitzer. From this information they could work out how much light the planet itself emits. As I recently reported, it is astonishing how much we are learning from these tiny pinpricks of light. Discovery team leader Professor Joseph Harrington, of the University of Central Florida, said: "HD 149026b is simply the most exotic, bizarre planet. It's pretty small, really dense, and now we find that it's extremely hot." Astronomers have so far found more than 230 planets around other stars, including Gliese 581, announced last month, the first that could resemble Earth with a rocky surface and oceans. Water vapour was detected in the atmosphere of another world and scientists say it is only a matter of time before they can analyse plant life on an alien planet! HD 149026b is only the fourth so-called exoplanet to have its temperature taken. Experts say that to be so hot, it must absorb virtually all the heat of its own sun that reaches it, making its surface blacker than charcoal. Professor Harrington said: "The high heat would make the planet glow slightly, so it would look like an ember in space, absorbing all incoming light but glowing a dull red." Nasa's Drake Deming, of the Goddard Space Flight Center, Maryland, who co-authored a paper on the discovery for the journal Nature, said: "This planet is off the temperature scale that we expect for planets, so we don't really understand what's going on. There may be more big surprises in the future." ©PAUL SUTHERLAND, Skymania.com • For more space reading, check out the Skymania stores in the USA and in the UK. They are powered by Amazon so you can buy with confidence.

Star's suicide is brightest ever seen

A space telescope has spotted the brightest exploding star ever seen in the universe. The supernova occurred in a distant galaxy but astronomers say a star in our own Milky Way could be lining itself up for a similar stellar suicide. When a star destroys itself in a monumental explosion, it briefly becomes as bright as all the thousands of millions of stars in one galaxy combined. The blast recorded by Nasa's Chandra X-ray Observatory and other telescopes was a hundred times more brilliant than normal. That leads scientists to believe that they may have detected a new type of supernova that they had long been seeking. Astronomer Alex Filippenko, who led ground-based observations from Lick Observatory, California, and the Keck Observatory on Hawaii, said: "Of all exploding stars ever observed, this was the king. We were astonished to see how bright it got, and how long it lasted." The wrecked star was probably as massive as it could be, at around 150 times the "size" of our own Sun. Astronomers say such violent explosions may have been fairly common in the early universe when a first generation of extremely massive stars existed. The suicide victim has been labelled SN 2006gy and lies 240 million light-years away in the galaxy NGC 1260 in the constellation of Perseus. Astronomers say the star gave an early warning of its demise by expelling a large cloud of material before the explosion itself was spotted on September 18 last year. This loss of mass is similar to matter seen ejected from Eta Carinae, a massive star lying just 7,500 light-years away in our own galaxy. Mario Livio of the Space Telescope Science Institute in Baltimore, commented: "We don't know for sure if Eta Carinae will explode soon, but we had better keep a close eye on it just in case. Eta Carinae's explosion could be the best star-show in the history of modern civilization." Eta's distance means, of course, that it could have gone bang already and we just don't know about it yet! An explosion would turn night into day in the southern hemisphere but go unseen from much of the northern hemisphere, such as London or New York, from where the star never rises. The supernova that appeared the brightest in recent history was SN 1987A, seen in 1987, which was only bright because it erupted in a satellite galaxy of our own Milky Way. Ten years later, it had left a stunning ring of pearls. A report on supernova SN 2006gy is to appear in the Astrophysical Journal. Photo: Astronomers from the University of California, Berkeley, took this infrared image showing SN 2006gy (right) and the nucleus of its host galaxy, NGC 1260. (Lick/UC Berkeley/J. Bloom & C. Hansen). ©PAUL SUTHERLAND, Skymania.com • For more space reading, check out the Skymania stores in the USA and in the UK. They are powered by Amazon so you can buy with confidence.

No yolk! Mercury has liquid core

Astronomers have used a classic technique for checking how well an egg is cooked to discover that Mercury has a molten core. Chefs will tell you that watching how a boiled egg spins will reveal whether its contents are solid or not. Planetary scientists managed to apply the test across millions of miles of space by bouncing radar signals from three radio telescopes. These revealed minute changes in the spin of the closest planet to the Sun. The subtle twists, called longitudinal librations, were twice as strong as would be expected from a solid "hard-boiled" world. But they matched one with a liquid centre. The three telescopes used for the discovery were Nasa's 70-meter antenna at Goldstone, Californis, the Arecibo Observatory in Puerto Rico and the Green Bank Telescope in West Virginia. The research was led by Jean-Luc Margot, assistant professor of astronomy at Cornell University, New York, and was published on the journal Science's website. Mercury is a rocky, terrestrial world like Earth. In size and appearance, however, it more closely resembles the Moon. It has a heavily cratered, mountainous surface that has been untouched by weathering because the planet has only a very tenuous atmosphere. Mercury, which has an average distance of 58 million km from the Sun, is believed to have had a particularly violent birth. The planet is known to contain unexpectedly high levels of iron. The theory is that this is because it was formed from an impact between a giant asteroid and a much larger world that was orbiting the Sun more than four billion years ago. A Nasa mission, called Messenger, has been en route there since 2004 but will not go into orbit around the planet until 2011. Another mission, BepiColombo, will carry two orbiters to Mercury, one European and one Japanese. The craft is not due for launch until 2013 and the probes will not arrive until six years later. Photo: Jean-Luc Margot with soft-boiled and hard-boiled spinning eggs. Credit: Lindsay France, Cornell University. ©PAUL SUTHERLAND, Skymania.com • For more space reading, check out the Skymania stores in the USA and in the UK. They are powered by Amazon so you can buy with confidence.

Search for new Earths gets a boost

The latest discovery of a planet orbiting another star has delighted astronomers because it suggests they might in future spot worlds as small as the Earth. The new find is another giant planet, nearly twice as wide as Jupiter, and is the first discovery by the Corot satellite launched by Europe on December 27 last year to seek out new worlds. It comes just days after another team of astronomers reported finding the first Earth-like planet beyond the solar system. As well as spotting the new planet, Corot was able to measure the first starquakes - ripples of seismic activity within a star. What has the scientists excited is the unexpected accuracy of Corot's measurements. It leads them to believe that they will not only be able to detect small rocky planets but also tell what sort of rocks are made of - i.e. their chemical composition. The new planet, labelled Corot-Exo-1b, zips around a Sun-like star in just a day and a half, making it another of the now familiar "hot Jupiters" that appear to be abundant in other solar systems. It was detected during a so-called transit when it passed in front of the star, causing a slight dimming of its light. The planet lies around 1,500 light-years from Earth in the constellation of Monoceros, the Unicorn. The margin of error in the data is so tiny that it means planets as small as Earth could be spotted by Corot - that is three times smaller than initially thought possible. If the satellite is able to detect subtle variations in the star's light reflected by the planet, it will indicate its chemical make-up. The starquake data was recorded by observing a star continuously for 50 days and is so accurate that the margin of error of is less than one part per million. The star showed large, unexpected luminosity variations on time scales of a few days, which may be related to the star's magnetic activity. Malcolm Fridlund, Corot Project Scientist for the European Space Agency, said: "The data we are presenting is still raw but exceptional. It shows that the on-board systems are working better than expected in some cases - up to ten times the expectation before launch. This will have an enormous impact on the results of the mission. Having seen its quality, we can expect great discoveries in the future." ©PAUL SUTHERLAND, Skymania.com • For more space reading, check out the Skymania stores in the USA and in the UK. They are powered by Amazon so you can buy with confidence.

Water ice is widespread on Mars

Water ice is spread widely across the surface of Mars in small patches, a new study reveals. Heat-sensing equipment on an orbiting probe has detected frozen deposits at various depths by penetrating several inches into the ground. Previous research has located vast deposits of ice at the martian south pole and signs that liquid water still bursts through crater walls. The latest findings are the most detailed ever for the presence of ice across Mars as a whole. They are said to support the idea of a cycle of activity where ice turns to running water and then evaporates into the atmosphere. Joshua Bandfield, of Arizona State University's School of Earth and Space Exploration, examined data sent back to Earth by the Thermal Emission Imaging System, THEMIS, on Nasa's Mars Odyssey spacecraft. This camera is so sensitive that it can image detail down to 330 ft in size (around 100 meters). The results build on those from another expriment on Odyssey, the Gamma Ray Spectrometer, which mapped ice at shallow depths but could only spot those 300 miles or more wide (about 500km). Dr Bandfield says: "We find the top layer of soil has a huge effect on the water ice in the ground." THEMIS is a sophisticated camera that takes images in 5 visual bands and 10 heat-sensing ones. At infrared wavelengths, the smallest details THEMIS can see on the surface are 330 feet (100 meters) wide. The new results were made using infrared images of several Martian sites, each at latitudes between 60 and 70 degrees, north and south. University colleague Professor Philip Christensen, who designed THEMIS, said: "Scientists have known for more than a decade that water is on Mars, mostly in the form of ice. What's exciting is finding out where the ice is in detail and how it got there. We've reached the next level of sophistication in our questions." Dr Bandfield, whose paper appears this week in the journal Nature, says that dusty areas of Mars tend to insulate the ice, allowing it to survive closer to the surface. Rocky areas pump heat into the ground and so the ice lies at greater depths. He says: "These two surface materials - rock and dust - vary widely across the ground, giving underground ice a patchy distribution." Dr Bandfield says his results fit long-term climatic models for Mars which show that the planet has been both warmer and colder in the past, similar to glacial cycles on Earth. He says: "The fact that ice is present near the depth of stability in the current Martian climate shows that the ground ice is responding to climate cycles." He adds: "The THEMIS measurements support an active water cycle on Mars such as other research has predicted." In August, Nasa is due to launch Phoenix, a mission designed to land at a high latitude on Mars and dig for a sample of ice to analyse. Photo: A THEMIS scan shows ice at different depths along a strip of Mars. Red marks the deepest ice, at least 19cms, or 7.5in, below the surface. (Nasa/JPL/Arizona State University). ©PAUL SUTHERLAND, Skymania.com • For more space reading, check out the Skymania stores in the USA and in the UK. They are powered by Amazon so you can buy with confidence.