Finnish researchers discover new type of black hole

Researchers at the University of Turku, in cooperation with international colleagues, have identified a new type of low-mass black hole. The type now discovered is a bright celestial object that emits x-rays.


NOTE : It is not possible to directly observe a black hole, but it is possible to detect events in its vicinity. An artist's concept of x-ray emissions from a black hole, published by NASA, August 2014

This new type of black hole has less mass than other known types and is associated with x-ray emitting quasars.

Up until now, it has been assumed that the collapse of a massive star generally forms a massive black hole or a small neutron star. The mass gap between neutron stars and stellar mass black holes is a question that has been a matter of inquiry for numerous research teams.

The object now discovered and designed SWIFT J1753.5-0127 has a mass somewhere between that of a conventionally-recognized black hole and a neutron star. Previously, observed neutron stars have been found to have less than two solar masses, while black holes have over five.

Observations related to this new type of low-mass black hole were published in a paper by a group of reseachers at the University of Turku, the Osservatorio Astronomico di Padova, the Max-Planck-Institut für Astronomie, and the INAF-IASF Milan branch, and published by the Monthly Notices of the Royal Astronomical Society.

Source : yle

Evidence Builds for Dark Matter Explosions at the Milky Way’s Core

This Fermi map of the Milky Way center shows an overabundance of gamma-rays (red indicates the greatest number) that cannot be explained by conventional sources.

So far, dark matter has evaded scientists’ best attempts to find it. Astronomers know the invisible stuff dominates our universe and tugs gravitationally on regular matter, but they do not know what it is made of. Since 2009, however, suspicious gamma--ray light radiating from the Milky Way’s core—where dark matter is thought to be especially dense—has intrigued researchers. Some wonder if the rays might have been emitted in explosions caused by colliding particles of dark matter. Now a new gamma-ray signal, in combination with those already detected, offers further evidence that this might be the case.

One possible explanation for dark matter is that it is made of theorized “weakly interacting massive particles,” or WIMPs. Every WIMP is thought to be both matter and antimatter, so when two of them meet they should annihilate on contact, as matter and antimatter do. These blasts would create gamma-ray light, which is what astronomers see in abundance at the center of our galaxy in data from the Fermi Gamma-Ray Space Telescope. The explosions could also create cosmic-ray particles—high-energy electrons and positrons (the antimatter counterparts of electrons)—which would then speed out from the heart of the Milky Way and sometimes collide with particles of starlight, giving them a boost of energy that would bump them up into the gamma-ray range. For the first time scientists have now detected light that matches predictions for this second process, called inverse Compton scattering, which should produce gamma rays that are more spread out over space and come in a different range of energies than those released directly by dark matter annihilation.

“It looks pretty clear from their work that an additional inverse Compton component of gamma rays is present,” says Dan Hooper, an astrophysicist at the Fermi National Accelerator Laboratory who was not involved in the study, but who originally pointed out that a dark matter signal might be present in the Fermi telescope data. “Such a component could come from the same dark matter that makes the primary gamma-ray signal we've been talking about all of these years.” University of California, Irvine scientists Anna Kwa and Kevork Abazajian presented the new study October 23 at the Fifth International Fermi Symposium in Nagoya, Japan and submitted their paper to Physical Review Letters.

None of the intriguing gamma-ray light is a smoking gun for dark matter. Other astrophysical processes, such as spinning stars called pulsars, can create both types of signal. “You can make models that replicate all this with astrophysics,” Abazajian says. “But the case for dark matter is the easiest, and there’s more and more evidence that keeps piling up.”

The official Fermi telescope team has long been cautious about drawing conclusions on dark matter from their data. But at last week’s symposium, the group presented its own analysis of the unexplained gamma-ray light and concluded that although multiple hypotheses fit the data, dark matter fits best. “That’s huge news because it’s the first time they’ve acknowledged that,” Abazajian says. Simona Murgia, an astrophysicist at the University of California, Irvine and a member of the Fermi collaboration’s galactic-center analysis team, presented the team’s findings. She says the complexity of the galactic center makes it difficult to know for sure how the excess of gamma rays arose and whether or not the light could come from mundane “background” sources. “It is a very interesting claim,” she says of Abazajian’s analysis. “However, detection of extended excesses in this region of the sky is complicated by our incomplete understanding of the background.”

The dark matter interpretation would look more likely if astronomers could find similar evidence of WIMP annihilation in other galaxies, such as the two dozen or so dwarf galaxies that orbit the Milky Way. “Extraordinary claims require extraordinary evidence, and I think a convincing claim of discovery would probably require a corresponding signal in another location—or by a non-astrophysical experiment—as well as the galactic center,” says Massachusetts Institute of Technology astrophysicist Tracy Slatyer, who has also studied the Fermi data from the Milky Way’s center.

Non-astrophysical experiments include the handful of so-called direct-detection experiments on Earth, which aim to catch WIMPs on the extremely rare occasions when they bump into atoms of normal matter. So far, however, none of these has found any evidence for dark matter. Instead they have steadily whittled away at the tally of possible types of WIMPs that could exist.

Other orbiting experiments, such as the Alpha Magnetic Spectrometer (AMS) on the International Space Station, which detects cosmic rays, have also failed to find convincing proof of dark matter. In fact, the AMS results seem to conflict with the most basic explanations linking dark matter to the Fermi observations. “Most people would agree that there is something rather unexpected happening at the galactic center, and it would be tremendously exciting if it turns out to be a dark matter annihilation signal,” says Christoph Weniger of the University of Amsterdam, another astrophysicist who has studied the Milky Way’s core. “But we have to confirm this interpretation by finding corroborating evidence in other independent observations first. Much more work needs to be done.”

Source : scientificamerican

Russian Cargo Ship Lifts Off For Space Station

An unmanned Russian cargo ship successfully lifted off for the International Space Station (ISS) on October 29.

The Progress 57 craft was launched atop a Soyuz rocket at 8:09 a.m. Prague time from the Russian-leased Baikonur facility in Kazakhstan.

"Everything looks good on the Soyuz booster and the Progress resupply ship," an announcer on the U.S. space agency's NASA TV said.

The launch came nine hours after a privately operated rocket exploded seconds after liftoff in the United States, causing the loss of cargo ship that was also bound for the ISS.

The explosion of the Antares was the first such accident since NASA turned to private operators to deliver cargo to the station, breaking a Russian monopoly that followed the retirement of the U.S. space shuttle fleet in 2011.

The Progress is delivering nearly three metric tons of propellant, oxygen, water, and other supplies to the station.

EXPLOSION OF NASA'S UNMANNED ROCKET ANTARES

An unmanned Antares rocket exploded seconds after liftoff from a commercial launch pad in Virginia on Tuesday, marking the first accident since NASA turned to private operators to deliver cargo to the International Space Station, but officials said no one was hurt.

The 14-story rocket, built and launched by Orbital Sciences Corp, blasted off its seaside launch pad at the Wallops Flight Facility at 6:22 p.m. EDT carrying a Cygnus cargo ship for the space station. It exploded in a huge fireball moments later.

Orbital Sciences stock was down 12.74 percent after hours, or down $3.87 at $26.50.

The cause of the accident was not immediately known, said NASA mission commentator Dan Huot.

Huot said there were no reports of any personnel in the vicinity of the explosion. An Accomack County Sheriff's spokeswoman added, "As far as we know, all personnel are accounted for and everyone's OK."

Orbital Sciences said in a statement: "We've confirmed that all personnel have been accounted for. We have no injuries in the operation today."

NASA launch control said damage appeared to be limited to the launch facility and rocket. The Antares rocket has been launched successfully on four previous missions.

"This has been a lot of hard work to get to this point," Orbital Sciences Executive Vice President Frank Culbertson told the launch team just before liftoff.

http://www.youtube.com/watch?v=hSJ2kcDirEo

Launch had been delayed one day after a boat sailed into a restricted safety zone beneath the rocket's intended flight path.

Virginia-based Orbital Sciences is one of two companies hired by NASA to fly cargo to the station after the space shuttles were retired. Tuesday's planned flight was to be the third of eight under the company's $1.9 billion contract with NASA.

The second U.S. supply line to the station is run by privately owned Space Exploration Technologies, or SpaceX, which is preparing for its fourth flight under a separate $1.6 billion NASA contract.

Outfitted with a new, more powerful upper-stage engine, the Antares rocket launched on Tuesday carried a Cygnus spacecraft packed with 5,055 pounds (2,293 kg) of supplies, science experiments and equipment, a 15 percent increase over previous missions.

Cygnus was to loiter in orbit until Nov. 2, then fly itself to the station so astronauts can use a robotic crane to snare the capsule and attach it to a berthing port. The station, a $100 billion research laboratory owned and operated by 15 nations, flies about 260 miles (418 km) above Earth.

In addition to food, supplies and equipment, the Cygnus spacecraft was loaded with more than 1,600 pounds (725 kg) of science experiments, including an investigation to chemically analyze meteors as they burn up in Earth’s atmosphere.

The Cygnus also carried a prototype satellite owned by Redmond, Washington-based startup Planetary Resources Inc., which is developing technology to mine asteroids. The satellite, designated A3, was to be released into space by a commercially owned small spacecraft launcher aboard the station.

Source : Reuters

High-Altitude Methane Ice Cloud Discovered Floating Above Titan's Pole

NASA scientists have uncovered a starting new find on Saturn's moon, Titan. They've found an unexpected high-altitude methane ice cloud, similar to exotic clouds formed high above Earth's own poles. This cloud in the stratosphere over Titan’s north pole (left) is similar to Earth’s polar stratospheric clouds (right). NASA scientists found that Titan’s cloud contains methane ice, which was not previously thought to form in that part of the atmosphere. Cassini first spotted the cloud in 2006. (Photo : L. NASA/JPL/U. of Ariz./LPGNantes; R. NASA/GSFC/M. Schoeberl)

NASA scientists have uncovered a starting new find on Saturn's moon, Titan. They've found an unexpected high-altitude methane ice cloud, similar to exotic clouds formed high above Earth's own poles.

The researchers first spotted the cloud with the help of NASA's Cassini spacecraft. It was part of the winter cap of condensation over Titan's north pole. Now, scientists have teased apart the data and found that the cloud contained methane ice, which produces a much denser cloud than the previously identified ethane ice.

"The idea that methane clouds could form this high on Titan is completely new," said Carrie Anderson, lead author of the new study, in a news release. "Nobody considered that possible before."

The temperatures in Titan's lower stratosphere are not the same at all latitudes. In fact, the high-altitude temperature near the north pole is far colder than just south of the equator. This temperature difference-as much as 11 degrees Fahrenheit-is enough to yield methane ice.

So how do these clouds form? The mechanisms for forming these high-altitude clouds are different from what happens in the troposphere. Titan has a global circulation pattern; warm air in the summer hemisphere wells up from the surface and enters the stratosphere, slowly making its way to the winter pole. There, the air sinks back down and cools as it descends. This forms the methane clouds.

Currently, the scientists are gathering more information about Saturn's moon in order to better understand the natural processes that occur on the alien world. This could shed light on the processes that occur on exoplanets and allow scientists to apply their findings to processes that also occur on Earth.

"Titan continues to amaze with natural processes similar to those on Earth, yet involving materials different from our familiar water," said Scott Edgington, Cassini deputy project scientist. "As we approach southern winter solstice on Titan, we will further explore how these cloud formation processes might vary with season."

Amazing picture of Supernova 1987A

Real image SN 1987A located at 1,68,000 light years from earth in Large Magellanic Cloud (Another Galaxy)

you can imagine the power of this supernova by understanding that even it was located at another galaxy it was visible to the naked eye. It was the first supernova that modern astronomers had to observe a SN and to use modern technology in that observation allowing them to gather much more data.

Supernovae are extremwely rare events. About 1 every 200 years is visible and they only last for a month or two.



image of SN 1987A

No sign of life detected on martian surface

The Curiosity rover used a laser to sample freshly drilled rock dust on Mars. It has not found methane.

NASA's Curiosity rover has failed to find significant signs of methane in the Martian atmosphere, mission scientists reported on Thursday. The new rover information suggests that earlier reports of Martian methane—once seen as a possible sign of microbial life on the planet—may have been off target.
If the Curiosity finding holds up, it would raise questions about one of the most intriguing discoveries made about Mars in recent years: that periodic and large-scale plumes of organic methane are released from beneath the planet's surface.
"We consider this to be a quite definitive conclusion, and we're very confident with it," Chris Webster, manager of the Planetary Science Instrument Office at NASA's Jet Propulsion Laboratory in Pasadena, California, said of the new rover readings reported in the journal Science.
"It puts an upper limit on the background methane on Mars that is very constraining of any scenarios for its production on the planet."
The special interest in the gas comes from the fact that some 90 percent of the methane on Earth is the product of living microbes. Signs of methane plumes in the Martian atmosphere seen by Earth-based telescopes had earlier raised hopes of detecting similar microbial life hidden under the Martian surface.
Original Discovery Defended
The lead author of that 2009 methane plume discovery report, Michael Mumma of NASA's Goddard Space Flight Center in Greenbelt, Maryland, said that he stood by his finding that substantial and localized plumes of methane were released on Mars in 2003.
He suggests that the Martian atmosphere destroys methane much more quickly than Earth's does, and that within three years of the original measurements new observations showed that half of the methane was gone.
"These findings are actually consistent with our results," Mumma said of the findings from Curiosity. "We reported that the methane releases are likely to be sporadic and that the methane is quickly eliminated in the atmosphere.
"The good news here is that the rover instrument designed to detect methane is working, and we look forward to ongoing monitoring in the future."
Other American and European researchers have also detected elevated levels of methane in the atmosphere of Mars—for example, the European Space Agency's Mars Express orbiting spacecraft found methane in 2004—but none with the specificity reported by Mumma's team.
Curiosity Counters Methane Reports
Webster said that he took the previous reports of methane on Mars "at face value," since they too were published in peer-reviewed journals. But he said the Curiosity observations were clearly different.
While methane can be produced through geological processes, on Earth it is overwhelmingly a byproduct of microbes called methanogens. Best known as denizens of the guts of creatures ranging from humans to cattle to termites, these organisms produce the marsh gas found in wetlands and landfills. But they can also live deep underground.
Because of the harsh environment on Mars—high levels of surface radiation; low temperatures; and dry, acidic conditions—scientists have generally agreed that any microbes now alive on the planet would likely inhabit the deep underground.
Mumma's team did not point to biology as the source of the methane plumes they identified, but they did raise it as a possibility along with geological processes.
Surface Measurements Will Continue
The new paper makes the case that the methane levels Curiosity detected on the ground are so low that the likelihood of a biological source is vanishingly small.
"Methane is a very well understood gas that is quite stable," Webster said. "We know how long it lasts and how it is destroyed over decades."
While it is conceivable that something exists in the Martian atmosphere that destroys methane at a much faster pace than on Earth, "we have no evidence, no observations of what it might be," he said.
Webster said the rover's instruments have not detected any methane so far, but the possibility of error put the upper limit of methane at 1.7 parts per billion. That means that the Martian atmosphere could hold at most about 10,000 tons (nine million kilograms) of methane, notes the University of Michigan's Sushil Atreya, a co-author on the new study. On Earth, the atmosphere holds about six billion tons (5.44 trillion kilograms) of methane.
The methane-detecting device is on the rover's Sample Analysis at Mars (SAM) instrument panel and is called the tunable laser spectrometer. Webster said that efforts to detect methane will continue, but will likely be reduced if results continue to come back negative.
A European satellite is scheduled to arrive at Mars in 2016 with the specific goal of searching for gases such as methane. The ExoMars Trace Gas Orbiter was initially going to be a joint venture with NASA, but the agency pulled out for budgetary reasons.