A normally dull star in Ursa Major, the Great Bear constellation, give off an incredible flare while scientists watched, increasing its brightness 15-fold in just three minutes, before returning to normal.
Dubbed WX UMa, the stellar body belongs to a rare class of variable stars known as flare stars, which suddenly and unpredictably boost their brightness in a matter of moments. But the flares are fleeting; these stars revert to their dimmer state in tens of minutes, researchers say.
WX UMa lies in a binary system in Ursa Major roughly 15.6 light years from Earth. It’s outshined by a companion star that’s 100 times brighter, except during the few times a year when WX UMa gives off luminous flares.
Researchers say they have seen WX UMa get fired up before, but never as dramatically as during their observations at the Byurakan Observatory in Armenia between May and June 2012.
“We recorded a strong flare of the star WX UMa, which became almost 15 times brighter in a matter of 160 seconds,” astrophysicist Vakhtang Tamazian, a professor at the University of Santiago de Compostela in Spain, told Spanish science news agency SINC. “Furthermore, during this period of less than three minutes the star underwent an abrupt change from spectral type M to B; in other words, it went from a temperature of 2,800 Kelvin (K) to six or seven times more than that.”
Such flares likely arise when instability within the plasma of the star causes turbulence in its magnetic field, Tamazian explained.
“A magnetic reconnection then occurs, a conversion of energy from the magnetic field into kinetic energy, in order to recover the stability of the flow, much like what happens in an electric discharge,” the researcher told SINC.
Tamazian said this kinetic energy transforms into thermal energy in the upper layers of the atmosphere and the star’s corona, driving up its temperature and brightness.
Because flare stars are weak, scientists can observe only the ones that are relatively nearby, up to a distance of a few tens of light years.
Researchers are particularly interested in flare stars in binary systems, Tamazian said, “because we can investigate whether there is any relation between the frequency of flares and the position of the pair of stars on their orbit, a question which remains open.”
The research was detailed in the journal Astrophysics.
KABOOM! Another day, another bomb explodes in a Muslim country and another rag-head blows himself to pieces thanks to his indoctrinated brain, indoctrinated by Islam – the religion of piss. TGO
Refer to brief story below. Source: Associated Press
BAGHDAD (AP) — Iraqi authorities say a suicide bomber has blown himself up amid worshippers in a Shiite mosque in Baghdad, killing eleven people and wounding 25.
Police officials said that the Tuesday occurred during midday prayers.
A medic in a nearby hospital confirmed the casualties. All officials spoke on condition of anonymity because they are not authorized to speak to media.
Violence has risen recently in Iraq, along with sectarian and political tensions. Insurgents frequently attack Shiites deemed by Sunni extremists as infidels and non-Muslims.
ANCHORAGE, Alaska (AP) — A black bear mauled a man at a campground in Alaska, but the animal won’t likely threaten other people, the state Department of Fish and Game said.
Spokesman Ken Marsh said the bear was “pretty much goaded” into the attack Saturday near Eklutna Lake Campground north of Anchorage because the man fed it meat from a church barbecue, the Anchorage Daily News (http://bit.ly/11sQbZW ) reported.
The man could be charged with illegally feeding wildlife, according to Alaska State Troopers spokeswoman Beth Ipsen. He had been drinking and went for a bike ride, taking some of the food along, she said. The man came across the bear and threw it a piece of meat. He then offered the bear another piece.
“That’s when it kind of went ballistic,” Ipsen said.
Park rangers later found the bloodied man washing himself off at the campground, Marsh said.
“He wasn’t terribly coherent,” he said. “He was unsure of where the attack actually happened.”
The man was treated for punctures wounds and scratches at an Anchorage hospital. His name was not immediately released.
Authorities are still trying to sort out what happened, Ipsen said. There were no witnesses to the attack and the man struggled to convey what had happened when a trooper spoke with him at the hospital, she said.
A state biologist sent to the scene couldn’t find the bear, Marsh said. There’s no indication the animal will attack others.
“The bear was pretty much goaded into this,” Marsh said.
Biologists advise people never to feed wild animals anything.
BAGHDAD (AP) — Three bomb attacks in Iraq including a blast in a roadside restaurant killed 15 people on Monday, officials said, the latest in a surge of violence that has left nearly 2,000 dead since the beginning of April.
The bomb left inside the restaurant in Taji, which serves travelers on the highway linking Baghdad to several northern Sunni-majority cities, killed eight people including two women and a 12-year-old child, two police officers said. Twenty-four others were wounded.
Also in Taji, a bomb placed inside a minibus killed two commuters and wounding 11 others, the police added. Taji is a former insurgent stronghold, located about 20 kilometers (12 miles) north of the Iraqi capital.
In the western town of Fallujah, a suicide bomber set off his explosives-laden belt among a group of policemen, killing five and wounding 24, another police said. The policemen were for waiting buses to be transferred them to a polling station to cast their ballots for Iraq’s provincial elections.
Fallujah, part of Anbar, is located 65 kilometers (40 miles) west of Baghdad. Iraq delayed April provincial elections there and in another Sunni-majority province, Ninevah, because of security instability. Residents of these provinces will cast their ballots on Thursday.
Three medical officials confirmed the casualty figures. All officials spoke on condition of anonymity as they were not authorized to release information.
The attack followed a day when at least 51 people were killed in a wave of bombs and shootings across Iraq. Violence has spiked sharply in Iraq in recent months, with the death toll rising to levels not seen since 2008. More than 190 have died this month alone.