Space

March 19,2008 marked the brightest ever cosmic explosion observed from Earth ( see Georg von Hippel's article here and the news article here). The outburst denoted as GRB 080319B was probably the death of a massive star leading to the creation of a black hole.

For the first time the birth of a black hole has been filmed. Cameras of the "Pi of the Sky" project recorded this remarkable event with a 4 minutes sequence of 10-second images. In under 20 seconds the object became so bright that it was visible with the naked eye. Then it began fading and in 4 minutes was 100 times fainter. At that time the observation was taken over by larger telescopes.

GRB 080319B brightnes measured by "Pi of the Sky" collaboration


White dwarfs are good timekeepers, and as such, hold clues about the age of the cosmos.

“Once a white dwarf forms, all it does is sit and cool, so we can measure the temperature of a white dwarf, and, using some theoretical understandings, figure out how long it took the star to cool to that temperature, and hence determine how old it is,” says Judi Provencal, assistant professor of physics and astronomy at the University of Delaware, director of the Delaware Asteroseismic Research Center (DARC), and resident astronomer at Mt. Cuba Astronomical Observatory in Greenville, Del.. “The coolest white dwarf we know of is about 2,500 degrees,” she notes. “This corresponds to an age for the galaxy of about 10 billion years.”


NASA's Cassini spacecraft tasted and sampled a surprising organic brew erupting in geyser-like fashion from Saturn's moon Enceladus during a close flyby on March 12. Scientists are amazed that this tiny moon is so active, "hot" and brimming with water vapor and organic chemicals.

New heat maps of the surface show higher temperatures than previously known in the south polar region, with hot tracks running the length of giant fissures. Additionally, scientists say the organics "taste and smell" like some of those found in a comet. The jets themselves harmlessly peppered Cassini, exerting measurable torque on the spacecraft, and providing an indirect measure of the plume density.


Astronomers using data from NASA’s Chandra X-ray Observatory, the Gemini Observatory and ESA’s XMM-Newton Observatory have made the best determination of the power of a supernova explosion long after it was visible from Earth.

By observing the remnant of a supernova that occurred about 400 years ago and a light echo from the initial explosion, the teams have established the validity of a new method for studying a type of supernova that produces most of the iron in the universe. The researchers studied the supernova remnant and the supernova light echo that are located in the Large Magellanic Cloud (LMC), a small galaxy about 160,000 light years from Earth

This combination of X-ray and optical images shows the aftermath of a powerful supernova explosion in the Large Magellanic Cloud (LMC), a small galaxy about 160,000 light years from Earth. The debris from this explosion (upper inset) shows the lowest energy X-rays are shown in red, the intermediate energies are green and the highest energies are blue. The light echo image (lower inset) shows light from the original supernova explosion that has bounced off dust clouds in the neighboring regions of the LMC (the light echoes are shown in blue and stars in orange). The large optical image shows emission lines of hydrogen (H-alpha) in red, singly-ionized sulfur in green and doubly-ionized oxygen in blue. The image highlights regions of star formation in the LMC, including supernova remnants and giant structures carved out by multiple supernovas. Credits:Chandra: NASA/CXC/Princeton/C.Badenes et al. MCELS: NOAO/AURA/NSF/S.Points, C.Smith & MCELS team. Light echo: NOAO/CTIO/Harvard/A.Rest et al.


As Georg von Hippel wrote about here, a powerful stellar explosion detected March 19 by NASA's Swift satellite has shattered the record for the most distant object that could be seen with the naked eye.

The explosion was a gamma ray burst. The Very Large Telescope in Chile and the Hobby-Eberly Telescope in Texas measured the burst's redshift at 0.94. A redshift is a measure of the distance to an object. A redshift of 0.94 translates into a distance of 7.5 billion light years, meaning the explosion took place 7.5 billion years ago, a time when the universe was less than half its current age and Earth had yet to form. This is more than halfway across the visible universe.

CLICK ABOVE FOR LARGER IMAGE. The extremely luminous afterglow of GRB 080319B was imaged by Swift's X-ray Telescope (left) and Optical/Ultraviolet Telescope (right). This was by far the brightest gamma-ray burst afterglow ever seen - and from 7.5 billion light years away. Credit: NASA/Swift/Stefan Immler, et al.


Located at the University of Utah, the High Resolution Fly's Eye (HiRes) is an experiment to study the highest energy cosmic rays to determine the energy, direction, and chemical composition of the incident particle.

Final results show that the most energetic particles in the universe rarely reach Earth at full strength because they come from great distances, so most of them collide with radiation left over from the birth of the universe.

The findings are based on nine years of observations at the now-shuttered observatory on the U.S. Army’s Dugway Proving Ground. They confirm a 42-year-old prediction – known as the Greisen-Zatsepin-Kuzmin (GZK) “cutoff,” “limit” or “suppression” – about the behavior of ultrahigh-energy cosmic rays, which carry more energy than any other known particle.

Gamma Ray Bursts are colossal cosmic explosions: in their death throes, supermassive stars collapsing into a black hole will send out a pair of powerful rays from their poles that carry away most of the energy of this incredibly violent event in a second-long burst of intense radiation, radiating away more energy in the blink of an eye than the Sun will during its entire lifetime of billions of years.

Life on another planet? No, it's far too hot on HD 189733b for that, but the Hubble Space Telescope's first ever detection of an organic molecule in the atmosphere of a planet orbiting another star is big news. It's an important step in eventually identifying signs of life on a planet outside our Solar System.

Hubble found the tell-tale signature of methane in the atmosphere of the Jupiter-sized extrasolar planet HD 189733b. Under the right circumstances, methane can play a key role in prebiotic chemistry – the chemical reactions considered necessary to form life as we know it. Although methane has been detected on most of the planets in our Solar System, this is the first time any organic molecule has been detected on a world orbiting another star.




Amino acids are organic molecules that are the backbone of the proteins that build many of the structures and drive many of the chemical reactions inside living cells. The production of proteins is believed to constitute one of the first steps in the emergence of life. Amino acids are truly the 'building blocks' of life on Earth but the presence of these compounds in meteorites has led some researchers to look to space as a source.

Scientists at the Carnegie Institution have discovered concentrations of amino acids in two meteorites that are more than ten times higher than levels previously measured in other similar meteorites. This result suggests that the early solar system was far richer in the organic building blocks of life than scientists had thought, and that fallout from space may have spiked Earth’s primordial broth.

In a find that sheds light on how Earth-like planets may form, astronomers this week reported finding the first evidence of small, sandy particles orbiting a newborn solar system at about the same distance as the Earth orbits the sun.

"Precisely how and when planets form is an open question," said study co-author Christopher Johns-Krull, assistant professor of physics and astronomy at Rice University. "We believe the disk-shaped clouds of dust around newly formed stars condense, forming microscopic grains of sand that eventually go on to become pebbles, boulders and whole planets."

In previous studies, astronomers have used infrared heat signals to identify microscopic dust particles around distant stars, but the method isn't precise enough to tell astronomers just how big they become, and whether the particles orbit near the star, like the Earth does the sun, or much further away at a distance more akin to Jupiter or Saturn.