Monday, March 23, 2009

The “Ultimate Jurassic Predator” Could Crush a Hummer in Its Jaws

On a Norwegian island within the Arctic Circle, researchers have unearthed the fossilized remains of a marine monster they call “Predator X.” The 50-foot beast is a new species of pliosaur, and researchers say the enormous reptile ruled the Jurassic seas some 147 million years ago…. “Its anatomy, physiology and hunting strategy all point to it being the ultimate predator – the most dangerous creature to patrol the Earth’s oceans” [New Scientist], the Natural History Museum at the University of Oslo said in a breathless press release.

Predator X swept through the seas some 147 million years ago during the Jurassic Period, when dinosaurs walked the land. The creature swam with its four flippers, and relied on its crushing jaw power to bring down its prey–lead researcher Joern Hurum estimates that its had 33,000 pounds per square inch bite force. Says Hurum: “With a skull that’s more than 10 feet long you’d expect the bite to be powerful but this is off the scale…. It’s much more powerful than T-Rex” [Reuters]. Hurum has said that a previously discovered fossil pliosaur was big enough to chomp on a small car. He said the bite estimates for the latest fossil forced a rethink. “This one is more like it could crush a Hummer,” he said [Reuters]. Hurum theorizes that the 45-ton predator feasted on fish and marine reptiles, including ichthyosaurs and long-necked plesiosaurs.

Paleontologists dug up the partial skull and the fragmented skeleton of a giant pliosaur last summer on the island of Spitsbergen. Fossil hunters get used to working in the heat and cold, the dry and wet, but even without counting the polar bears nosing around their dig, Spitsbergen posed unusual challenges. It has only a three-week window for excavating, from the end of July through much of August. That is after the warmth of a brief summer has thawed upper layers of the ground and before the onset of the round-the-clock darkness of Arctic winter [The New York Times]. A documentary about the expedition will be shown on the History Channel later this month.

The researchers haven’t yet given the new species a scientific name, and although they’ve described their findings at scientific conferences, they have yet to publish their work in a peer-reviewed journal–they say that will happen later this year.

Wednesday, March 11, 2009

Trio of Galaxies Mix It Up

Release No. STScI-2009-10
Image Credit: NASA, ESA, and R. Sharples (University of Durham)

Though they are the largest and most widely scattered objects in the universe, galaxies do go bump in the night. The Hubble Space Telescope has photographed many pairs of galaxies colliding. Like snowflakes, no two examples look exactly alike. This is one of the most arresting galaxy smash-up images to date.

At first glance, it looks as if a smaller galaxy has been caught in a tug-of-war between a Sumo-wrestler pair of elliptical galaxies. The hapless, mangled galaxy may have once looked more like our Milky Way, a pinwheel-shaped galaxy. But now that it's caught in a cosmic Cuisinart, its dust lanes are being stretched and warped by the tug of gravity. Unlike the elliptical galaxies, the spiral is rich in dust and gas for the formation of new stars. It is the fate of the spiral galaxy to be pulled like taffy and then swallowed by the pair of elliptical galaxies. This will trigger a firestorm of new stellar creation.

If there are astronomers on any planets in this galaxy group, they will have a ringside seat to seeing a flurry of starbirth unfolding over many millions of years to come. Eventually the ellipticals should merge too, creating one single super-galaxy many times larger than our Milky Way. This trio is part of a tight cluster of 16 galaxies, many of them being dwarf galaxies. The galaxy cluster is called the Hickson Compact Group 90 and lies about 100 million light-years away in the direction of the constellation Piscis Austrinus, the Southern Fish.

Hubble imaged these galaxies with the Advanced Camera for Surveys in May 2006.

The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency (ESA) and is managed by NASA's Goddard Space Flight Center (GSFC) in Greenbelt, Md. The Space Telescope Science Institute (STScI) conducts Hubble science operations. The institute is operated for NASA by the Association of Universities for Research in Astronomy, Inc., Washington, D.C.

STScI is an International Year of Astronomy 2009 (IYA 2009) program partner.