37 years to the day after the first ever docking of American and Russian spacecraft


NASA astronaut Suni Williams, Japan Aerospace Exploration Agency astronaut Aki Hoshide and Russian cosmonaut Yuri Malenchenko joined their Expedition 32 crewmates at the International Space Station early Tuesday.

The docking occurs 37 years to the day after the first ever docking of American and Russian spacecraft during the 1975 Apollo-Soyuz mission. Read more HERE.

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By enigma Posted in News

Venus passing the sun… -Great picture!


Venus glided in front of the Sun for over six hours (June 5 – 6, 2012). SDO implemented specially planned operations to view the event in great detail in many wavelengths of light. The results were the best HD views of a transit ever taken. The image and movie shown here were taken in the 171 Angstrom wavelength of extreme UV light.

Credit: http://www.nasa.gov/mission_pages/sunearth/index.html 27.06.2012   20:27

 

Giant Black Hole Kicked Out of Home Galaxy


Astronomers have found strong evidence that a massive black hole is being ejected from its host galaxy at a speed of several million miles per hour. New observations from NASA’s Chandra X-ray Observatory suggest that the black hole collided and merged with another black hole and received a powerful recoil kick from gravitational wave radiation.

“It’s hard to believe that a supermassive black hole weighing millions of times the mass of the sun could be moved at all, let alone kicked out of a galaxy at enormous speed,” said Francesca Civano of the Harvard-Smithsonian Center for Astrophysics (CfA), who led the new study. “But these new data support the idea that gravitational waves — ripples in the fabric of space first predicted by Albert Einstein but never detected directly — can exert an extremely powerful force.” Read more HERE.

 

Black Hole Caught Red-handed in a Stellar Homicide


Astronomers have gathered the most direct evidence yet of a supermassive black hole shredding a star that wandered too close.

Supermassive black holes, weighing millions to billions times more than the Sun, lurk in the centers of most galaxies. These hefty monsters lay quietly until an unsuspecting victim, such as a star, wanders close enough to get ripped apart by their powerful gravitational clutches.

Astronomers have spotted these stellar homicides before, but this is the first time they can identify the victim. Using a slew of ground- and space-based telescopes, a team of astronomers led by Suvi Gezari of The Johns Hopkins University in Baltimore, Md., has identified the victim as a star rich in helium gas. The star resides in a galaxy 2.7 billion light-years away.

Her team’s results will appear May 2 in the online edition of the journal Nature.

Read more HERE.

 

Black Hole Outburst in Spiral Galaxy M83


NASA’s Chandra X-ray Observatory has discovered an extraordinary outburst by a black hole in the spiral galaxy M83, located about 15 million light years from Earth. Using Chandra, astronomers found a new ultraluminous X-ray source (ULX), objects that give off more X-rays than most “normal” binary systems in which a companion star is in orbit around a neutron star or black hole.

On the left is an optical image of M83 from the Very Large Telescope in Chile, operated by the European Southern Observatory. On the right is a composite image showing X-ray data from Chandra in pink and optical data from the Hubble Space Telescope in blue and yellow. The ULX is located near the bottom of the composite image.

In Chandra observations that spanned several years, the ULX in M83 increased in X-ray brightness by at least 3,000 times. This sudden brightening is one of the largest changes in X-rays ever seen for this type of object, which do not usually show dormant periods.

Optical images reveal a bright blue source at the position of the ULX during the X-ray outburst. Before the outburst the blue source is not seen. These results imply that the companion to the black hole in M83 is a red giant star, more than about 500 million years old, with a mass less than about four times the Sun’s. According to theoretical models for the evolution of stars, the black hole should be almost as old as its companion.

Read more HERE.

 

Exciting news for Amateur Astronomers…


I saw this on NASA:s website today! I think it´s really exciting for those who have the possibility to do this.

“A new NASA outreach project will enlist the help of amateur astronomers to discover near-Earth objects (NEOs) and study their characteristics. NEOs are asteroids with orbits that occasionally bring them close to the Earth.” Read more HERE.

 

Sirius in the constellation “Canis Major” tonight (21:th March)


 

Look southward at dusk and nightfall, and you can’t miss Sirius, the brightest star in the nighttime sky. Only the planets Venus and Jupiter are brighter, but they’re in the western sky, due to be near the waxing crescent moon beginning around March 23. Venus and Jupiter are temporary visitors to our sky at this time of year. Sirius is a permanent fixture of March skies, where it always outshines other stars.

 

Sirius, in the constellation Canis Major (the Greater Dog), looks extraordinarily bright in Earth’s sky because it’s only 8.6 light-years away. Many stars on the sky’s dome are intrinsically more luminous than Sirius but appear fainter because they lie farther away.

At least three stars in Canis Major are thought to be thousands of times more luminous than Sirius: Aludra, Wezen, and Omicron 2. Although the distances to these faraway stars are not known with precision, Aludra and Omicron 2 reside an estimated 3,000 light-years distant, and Wezen at about 2,000 light-years.

To get a better idea of a star’s true luminosity, astronomers like to list stars according to “absolute magnitude.” Absolute magnitude measures the brightness of the stars as if they were all an equal 32.6 light-years distant.

At 32.6 light-years away, our sun would barely be visible as a speck of light. In stark contrast, Aludra, Wezen, and Omicron 2 at 32.6 light-years distance would outshine Sirius (at its distance of 8.6 light-years) by some one to two hundred times. At 32.6 light-years, Sirius would be about the same brightness as the Gemini star Castor. So if all these stars were equally distant, these super-luminous stars in Canis Major would shine thousands of times more brilliantly than Sirius.

Once again, absolute visual magnitude measures the star’s brightness as it would appear to the eye at 32.6 light-years away. Apparent visual magnitude refers to a star’s brightness as seen by the eye from Earth.

Bottom line: Sirius is our sky’s brightest star (although not as bright as the planets Venus and Jupiter, now in the west after sunset), but not the most luminous star in the sky. In other words, it’s an ordinary star that only appears bright to us because it is relatively nearby.

The Stellar Magnitude System by Alan M. MacRobert

Big Sunspot Remains Active


On March 13, 2012, the sun erupted with an M7.9-class flare that peaked at 1:41 p.m. EDT. This flare was from the same active region, No. 1429, that has been producing flares and coronal mass ejections all week. That region has been moving across the face of the sun since March 2, and will soon rotate out of Earth view.

NASA’s Solar Dynamics Observatory (SDO) captured this image of an M7.9 class flare on March 13, 2012 at 1:29 p.m. EDT. It is shown here in the 131 Angstrom wavelength, a wavelength particularly good for seeing solar flares and a wavelength that is typically colorized in teal. (Image credit: NASA/SDO)

More Than 1,000 Potential New Planets Found


Discoveries nearly double possible worlds spotted by Kepler mission.

More than a thousand potential new planets have been found outside our solar system—nearly doubling the number of candidates discovered so far by NASA’s Kepler space telescope, according to a new study.

The fresh batch of Kepler Objects of Interest, or KOIs, emerged from an analysis of mission data gathered between May 2009 and September 2010.

The data revealed 1,091 possible new planets, bringing the total count to 2,321—up from 1,235 candidates formally announced last February.

Read more HERE.