Hubble spots a planet-eating star
Page last updated at 9:16 GMT, Monday, 24 May 2010 10:16 UK
Scientists used Hubble data to create an image of the planet being swallowed The Hubble Space Telescope has captured evidence of a Sun-like star "eating" a nearby planet.
Astronomers knew that stars were capable of swallowing planets in orbit around them, but this is the first time the event has been "seen" so clearly.
Although the planet was too far away for Hubble to photograph, scientists have created an image of it, based on analysis of the telescope's data.
The discovery was published in the The Astrophysical Journal Letters.
Carole Haswell Open UniversityWe have identified chemical elements never before seen on planets outside our own Solar System
The researchers say the planet, which is called Wasp-12b, may only have another 10 million years left before it is completely devoured.
It is so close to its star that it completes an orbit in 1.1 Earth days and is superheated to more than 1,500C.
Because of this proximity, the planet's atmosphere has ballooned to nearly three times the radius of Jupiter and is spilling material on to the star.
Carole Haswell from the UK's Open University led the research team. She explained: "We see a huge cloud of material around the planet which is escaping and will be captured by the star."
Hubble's detection of the cloud enabled scientists to draw conclusions about how it was generated.
Dr Haswell said: "We have identified chemical elements never before seen on planets outside our own Solar System."
Wasp-12 is a dwarf star located approximately 600 light-years away in the constellation Auriga.
The exoplanet was first discovered by the UK's Wide Area Search for Planets (Wasp) in 2008.
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Persistent cold, wet weather delays crop harvests, worries farmers
Keep your sweater – and umbrella – within reach.
The chilly weekend temperatures were among the coldest in more than a half-century from Redding to Stockton, the National Weather Service reported Sunday.
More cold is expected today – a low of 45 and a high of 69 in downtown Sacramento – with rain forecast through much of this week.
The dogged pattern of rain and cold has prompted worries of another sort: Melon crops are less likely to be ready for market in time for July 4 celebrations, and tomato harvests likely will be delayed.
Cold "slows everything down," Yolo County Agriculture Commissioner John Young said Sunday. "We're not getting the temperatures we need for germination of seed. It slows the melons down, it slows the rice down, it slows any of the warm-weather crops."
Of course, the cooler temperatures have an upside, delaying Sierra snowmelt. On Friday the state Department of Water Resources boosted the delivery forecast for its customers to 45 percent of contract amounts, reflecting a snowpack that's at 167 percent of normal.
In the Valley, however, the regular cycle of spring rains threatens to narrow the timetable for tomato harvests, said Gene Miyao, farm adviser for the University of California Cooperative Extension.
Growers try to plant while soils are dry.
"Under wet conditions, (planting) causes soil compactions. That affects root growth. Irrigation doesn't infiltrate as well," Miyao said. "I think it certainly is a concern."
Waiting for soil to dry means risking that rain will fall again before planting. In that case, greenhouse growers can't move young-plant inventory to fields on schedule. And at harvest time, some growers must waiting for processor capacity. Tomatoes may rot in the field or face exposure to insects while waiting, Miyao said.
The late rains are no better for hay baling.
"If you get anywhere up to a half-inch or more (rain), you're going to start getting problems with mold," said Casey Stone, a partner in the 7,500-acre Yolo Land & Cattle Co. The company has about 600 Yolo County acres in hay.
Wind can help dry the hay. Winds from the northwest were forecast at 15 to 25 mph Sunday night in the Sacramento area.
And the forecast for rain? Figure on 0.2 to 0.5 of an inch of rain or showers starting by nightfall Tuesday, said Drew Peterson, National Weather Service meteorologist. Rain and showers will continue through Friday as a series of fronts arrive from the Gulf of Alaska.
Rainfall in downtown Sacramento, at 18.99 inches, is 97 percent of normal since July 1.
Not so normal is the late-season cold, which set records over the weekend.
"We're actually watching a record set in 1971," Peterson said. "We're looking to see if we make it through June 6 without a 90-degree day."
The warmest days downtown this year were 86 on May 3 and May 15. That triggered a premature chorus among weather-watchers.
"Everybody was saying, 'Summer is finally here,' " Peterson said.
For the record-setting, consider the weekend just ended.
Sunday's low of 45 degrees in downtown Sacramento matched the low established on that day in 1960. In Red Bluff, the low of 45 matched the low set in 1953. In Redding, the low was 42 on Sunday and on the same date in 1946.
On Saturday, the thermometer in Redding fell to 34 degrees, toppling the 39-degree record on that date in 1960. Red Bluff's low fell to 37 degrees, 3 degrees below the dates in 1960.
At the other end of the how-cold-it-got scale, Stockton Metropolitan Airport on Saturday never exceeded 67 degrees, two degrees lower than the coldest high for that day, set in 1943.
http://www.sacbee.com/2010/05/24/2771679/persistent-cold-wet-weather-stunts.html
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