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Progress 44 Fails to Reach Orbit

August 25, 2011 Leave a comment

Bound for the International Space Station, Progress 44 was launched from Baikonur Cosmodrome at 15:00 CEST yesterday but failed to reach its target orbit and crashed in Siberia, Russia. Five minutes and 50 seconds after launch, an “off-nominal situation” was reported, with a loss of telemetry.

Full Story: http://www.esa.int/esaCP/SEMGNQRTJRG_index_0.html

A Planet Made of Diamond

August 25, 2011 Leave a comment

An artist's visualisation of the pulsar and its orbiting planet. Image credit – Swinburne Astronomy Productions

An artist's visualisation of the pulsar and its orbiting planet. Image credit – Swinburne Astronomy Productions

A once-massive star that’s been transformed into a small planet made of diamond: that’s what astronomers think they’ve found in our Milky Way.

The discovery has been made by an international research team, led by Professor Matthew Bailes of Swinburne University of Technology in Melbourne, Australia, and is reported in today’s [Thursday August 25, 2011] issue of the journal Science.

Although bizarre, the “diamond planet” is in accord with our current picture of how certain binary star systems form.

The researchers, from Australia, Germany, Italy, the UK and the USA first detected an unusual star called a pulsar using the 64-m Parkes radio telescope of the Australian Commonwealth Scientific and Industrial Research Organisation (CSIRO) and followed up their discovery with the Lovell radio telescope in the UK and one of the Keck telescopes in Hawaii.

Pulsars are small spinning stars about 20 km in diameter — the size of a small city — that emit a beam of radio waves. As the star spins and the radio beam sweeps repeatedly over Earth, radio telescopes detect a regular pattern of radio pulses.

For the newly discovered pulsar, known as PSR J1719-1438, the astronomers noticed that the arrival times of the pulses were systematically modulated. They concluded that this was due to the gravitational pull of a small companion planet, orbiting the pulsar in a binary system.

The pulsar and its planet are part of the Milky Way’s plane of stars and lie 4,000 light-years away in the constellation of Serpens (the Snake). The system is about an eighth of the way towards the galactic center from the Earth.

The modulations in the radio pulses tell astronomers several things about the planet.

First, it orbits the pulsar in just two hours and ten minutes, and the distance between the two objects is 600,000 km — a little less than the radius of our Sun.

Second, the companion must be small, less than 60,000 km (that’s about five times the Earth’s diameter). The planet is so close to the pulsar that, if it were any bigger, it would be ripped apart by the pulsar’s gravity.

But despite its small size, the planet has slightly more mass than Jupiter.

“This high density of the planet provides a clue to its origin”, said Professor Bailes.

A Star Is Torn

The team thinks that the “diamond planet” is all that remains of aonce-massive star, most of whose matter was siphoned off towards the pulsar.

Pulsar J1719-1438 is a very fast-spinning pulsar — what’s called a millisecond pulsar. Amazingly, it rotates more than 10,000 times per minute, and has a mass of about 1.4 times that of our Sun, but is only 20 km in diameter. About 70 per cent of millisecond pulsars have companions of some kind. Astronomers think it is the companion that, in its star form, transforms an old, dead pulsar into a millisecond pulsar by transferring matter and spinning it up to a very high speed. The result is a fast-spinning millisecond pulsar with a shrunken companion — most often a so-called white dwarf.

“We know of a few other systems, called ultra-compact low-mass X-ray binaries, that are likely to be evolving according to the scenario above and may likely represent the progenitors of a pulsar like J1719-1438,” said team member Dr. Andrea Possenti, Director at INAF-Osservatorio Astronomico di Cagliari.

But pulsar J1719-1438 and its companion are so close together that the companion can only be a very stripped-down white dwarf, one that has lost its outer layers and over 99.9 per cent of its original mass.

“This remnant is likely to be largely carbon and oxygen, because a star made of lighter elements like hydrogen and helium would be too big to fit the measured orbit,” said Dr. Michael Keith (CSIRO), one of the research team members.

The density means that this material is certain to be crystalline: that is, a large part of the star may be similar to a diamond.

“The ultimate fate of the binary is determined by the mass and orbital period of the donor star at the time of mass transfer. The rarity of millisecond pulsars with planet-mass companions means that producing such exotic planets is the exception rather than the rule, and requires special circumstances,” said Dr. Benjamin Stappers from the University of Manchester.

The team found pulsar J1719-1438 among almost 200,000 gigabytes of data using special codes on supercomputers at Swinburne University of Technology in Australia, The University of Manchester in the UK, and the INAF-Osservatorio Astronomico di Cagliari, Italy.

The discovery was made during a systematic search for pulsars over the whole sky that also involves the 100 meter Effelsberg radio telescope of the Max-Planck-Institute for Radio Astronomy (MPIfR) in Germany. “This is the largest and most sensitive survey of this type ever conducted. We expected to find exciting things, and it is great to see it happening. There is more to come!,” said Professor Michael Kramer, Director at the MPIfR.

Professor Matthew Bailes leads the “Dynamic Universe” theme in a new wide-field astronomy initiative in Australia, the Centre of Excellence for All-sky Astrophysics (CAASTRO).

The discovery of the new binary system is of special significance for him and fellow team member Professor Andrew Lyne, who jointly ignited the whole pulsar-planet field in 1991 with what proved to an erroneous claim of the first extra-solar planet. The next year though the first extra-solar planetary system was discovered around the pulsar PSR B1257+12.

More info: http://www.scienceimage.csiro.au/mediarelease/mr11-diamond.html

Exotic Galaxy Reveals Tantalizing Tale

August 25, 2011 Leave a comment

CREDIT: Hota et al., SDSS, NCRA-TIFR, NRAO/AUI/NSF.

CREDIT: Hota et al., SDSS, NCRA-TIFR, NRAO/AUI/NSF.

A galaxy with a combination of characteristics never seen before is giving astronomers a tantalizing peek at processes they believe played key roles in the growth of galaxies and clusters of galaxies early in the history of the Universe.

The galaxy, dubbed Speca by the researchers, is only the second spiral, as opposed to elliptical, galaxy known to produce large, powerful jets of subatomic particles moving at nearly the speed of light. It also is one of only two galaxies to show that such activity occurred in three separate episodes.

 

 

 

Full Story: http://www.nrao.edu/pr/2011/spiralradio/

Seattle Students Chat With Space Station Astronauts On Monday

August 25, 2011 Leave a comment

Students gathered at the Museum of Flight in Seattle will make a long distance call to astronauts aboard the International Space Station at approximately 1:35 p.m. EDT on Monday, Aug. 29.

Students from Aviation High School, Puyallup High School, Civil Air Patrol and Liberty High School will ask Expedition 28 Flight Engineers Ron Garan, Mike Fossum and Satoshi Furukawa questions about life, work and research in space. The event will include a video link with the three astronauts and will be broadcast live on NASA Television.

Full Story: http://www.nasa.gov/home/hqnews/2011/aug/HQ_M11-179_Downlink.html

Cygnus Space Station Cargo Carrier Arrives At NASA Wallops

August 25, 2011 Leave a comment

NASA’s work to help develop the next generation of commercial space transportation systems reached another significant achievement yesterday with the arrival at Wallops Flight Facility in Virginia of the Cygnus Pressurized Cargo Module, Orbital Science Corp.’s spacecraft to carry supplies to the International Space Station.

Full Story: http://www.nasa.gov/home/hqnews/2011/aug/HQ_11-276_Cygnus.html

NASA Moon Mission In Final Preparations For September Launch

August 25, 2011 Leave a comment

NASA’s Gravity Recovery And Interior Laboratory (GRAIL), mission to study the moon is in final launch preparations for a scheduled Sept. 8 launch onboard a Delta II rocket from Cape Canaveral Air Force Station in Florida.

Full Story: http://www.nasa.gov/home/hqnews/2011/aug/HQ_11-275_GRAIL_Update.html

NASA’S Swift Satellite Spots Black Hole Devouring A Star

August 25, 2011 Leave a comment

Two studies appearing in the Aug. 25 issue of the journal Nature provide new insights into a cosmic accident that has been streaming X-rays toward Earth since late March. NASA’s Swift satellite first alerted astronomers to intense and unusual high-energy flares from the new source in the constellation Draco.

Full Story: http://www.nasa.gov/home/hqnews/2011/aug/HQ_11-271_Swift_Black_Hole.html

NASA And ATK Full-Scale Solid Rocket Motor Test Set For Sept. 8

August 25, 2011 Leave a comment

NASA and Alliant Techsystems Inc. (ATK) will conduct a full-scale test of a five-segment, solid rocket motor at the ATK Aerospace Systems test facility in Promontory, Utah, at 4:05 p.m. EDT, Thursday, Sept. 8.

Full Story: http://www.nasa.gov/home/hqnews/2011/aug/HQ_M11-177_Rocket_Test.html