April 20, 2009 -- The coolest star-like object ever found outside the solar system has been spotted around 40 light-years away from Earth. Christopher Tinney of the University of New South Wales and colleagues will report their discovery of a new brown dwarf in Monthly Notices of the Royal Astronomical Society. "It's certainly one of the coolest objects ever found," said Tinney. Unlike sun-like stars, brown dwarfs are too low in mass to burn nuclear fuel. So in the world of stars, they are very cold, dim and hard to study. Tinney and colleagues struck it lucky while on a wider search for the coolest and dimmest bodies in the local galactic neighborhood. Using a small telescope in Hawaii, they noticed the brown dwarf tracking across the sky along with a well-known red dwarf by the name of Wolf 940. Red dwarfs are brighter than brown dwarfs, being big enough to burn nuclear fuel, albeit much more slowly than fully-fledged stars. Tinney and colleagues dubbed the brown dwarf Wolf 940B, after the red dwarf it orbits. Related Content:
They believe the Jupiter-sized Wolf 940B formed like a star with an infrared spectrum strikingly similar to our solar system's biggest planet. But the brown dwarf is much denser being 20 to 30 times heavier, with a higher temperature of 300 degrees Celsius. Tinney said it is normally quite hard to measure the distances of brown dwarfs because they are so dim. But in this case, the researchers were able to immediately work out the distance of Wolf 940B because they knew the distance of the red dwarf it was orbiting. Finding low mass objects like Wolf 940B is interesting to scientists because it sheds light on other cool-temperature low-mass objects like extrasolar planets. "At the Anglo-Australian Observatory we have found 30 planets orbiting other stars, but we don't actually see the planet itself. We don't see what its atmosphere looks like," said Tinney. "Looking at systems like this gives us hints as to what the atmospheres of extrasolar planets might look like." The researchers now hope to point a much bigger telescope at Wolf 940B to get more details on its atmosphere, which can be used to help build more reliable models. The team used the United Kingdom Infrared Telescope and Gemini-North Telescope on Mauna Kea, Hawaii. Telescopes in Chile, the Canary Islands, Hawaii and the NASA's Spitzer Space Telescope have confirmed the findings. Related Links: HowStuffWorks.com: Brown Dwarfs Explained Get More NewsSpiders, Scorpions Among World's Oldest CreaturesMany creepy crawlies have been on Earth much longer than previously believed.Blood-Sucking Vampire Bats Sing DuetsWhite-winged vampire bats "harmonize" with separated roost mates.Oldest Hebrew Writing Possibly FoundAncient inscriptions on a 3,000-year-old pottery shard could make history.Rare, Prehistoric-Age Reptile Found in N.Z.A tuatara has been spotted on the New Zealand mainland for the first time in 200 years.Iceman Has No Living RelativesOetzi, the 5,300 year-old frozen mummy, left no living genetic legacy.SLIDE SHOW: Landscapes of TerrorWhat makes a place feel scary? There are scientific explanations.It's Official: People Are Warming the PolesHumans are conclusively to blame for polar warming, say scientists.Eight-Armed Animal Preceded DinosaursWhat may be one of Earth's first animals was no bigger than a coaster and had eight arms.Phoenicians Live on in People's GenesOne in 17 Mediterranean men may be descended from ancient Phoenicians.Pesticides, Fertilizers Linked to Frog DeclineA pesticide is found to promote parasites among amphibians.Hubble Telescope Taking Photos AgainThe Hubble Space Telescope is once again snapping stunning photos of the universe.Andean Mummy Hairs Show Hallucinogen UseScientists find direct evidence of hallucinogenic drug use among ancient Andeans.Opals on Mars Reveal Planet's Long Wet PastOpals found on Mars suggest the planet has been wet for much longer. |
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