Pleiades-the star cluster in the Taurus constellation

The Pleiades star cluster, also known as the Seven Sisters and Messier 45, is a conspicuous object in the night sky with a prominent place in ancient mythology. The cluster contains hundreds of stars, of which only a handful are commonly visible to the unaided eye. The stars in the Pleiades are thought to have formed together around 100 million years ago, making them 1/50th the age of our sun, and they lie some 130 parsecs (425 light years) away. From our perspective they appear in the constellation of Taurus, with approximate celestial coordinates of 3 hours 47 minutes right ascension and +24 degrees declination. For northern hemisphere viewers, the cluster is above and to the right of Orion the Hunter as one faces south, and it transits -- reaches its highest point in the sky, midway between rising and setting -- around 4am in September, midnight in November, and 8pm in January.

The image at the top of the page shows the central part of the cluster, where the brightest stars are found. This color photograph was taken in three filters, each exposed for about a half-hour, by David Malin with the UK Schmidt Telescope. The image is roughly 1.5 degrees wide, or three times the angular diameter of the moon. North is up and east is to the left. The cluster distance of 130 parsecs makes the physical width of the picture about 3.4 parsecs (11 light years); the cluster itself has a width perhaps 10 times greater, but most of the bright stars are found within one or two degrees of the core.

New Light On Galactic Pair – M81 and M82

A WISE Look At Messier 81 and Messier 82

 Almost every amateur astronomer has viewed the ghostly glow of galactic pair, Messier 81 and Messier 82. They’re easily visible in small binoculars from a dark sky site and reveal wonderful details in a telescope as aperture increases. We’ve marveled over M81′s smooth, star-rich structure and the disturbed spindle-shaped structure of M82. We know the pair have interacted and the huge spiral has ingested stars from its companion – but today we know a whole lot more…

According to today’s press release from the American Astronomical Society, when the pair swept by each other, gravitational interactions triggered new bursts of star formation. In the case of Messier 82, also known as the Cigar Galaxy, the encounter has likely triggered a tremendous wave of new star birth at its core. Intense radiation from newborn massive stars is blowing copious amounts of gas and smoky dust out of the galaxy, as seen in the WISE image in yellow hues. The Cigar Galaxy is pictured above Messier 81. “What’s unique about the WISE view of this duo is that we can see both galaxies in one shot, and we can really see their differences,” said Ned Wright of UCLA, the principal investigator of WISE. “Because the Cigar Galaxy is bursting with star formation, it’s really bright in the infrared, and looks dramatically different from its less active companion.”

The WISE mission completed its main goal of mapping the sky in infrared light in October 2010, covering it one-and-one-half times before its frozen coolant ran out, as planned. During that time, it snapped pictures of hundreds of millions of objects, the first batch of which will be released to the astronomy community in April 2011. WISE is continuing its scan of the skies without coolant using two of its four infrared channels — the two shorter-wavelength channels not affected by the warmer temperatures. The mission’s ongoing survey is now focused primarily on asteroids and comets. Because WISE has imaged the entire sky, it excels at producing large mosaics like this new picture of Messier 81 and Messier 82, which covers a patch of sky equivalent to three-by-three full Moons, or 1.5 by 1.5 degrees.

It is likely these partner galaxies will continue to dance around each other, and eventually merge into a single entity. They are both spiral galaxies, but Messier 82 is seen from an edge-on perspective, and thus appears in visible light as a thin, cigar-like bar. (To me it has always looked like a child’s dirty kite string wrapped around a stick, eh?) When viewed in infrared light, Messier 82 is the brightest galaxy in the sky. It is what scientists refer to as a starburst galaxy because it is churning out large numbers of new stars. “The WISE picture really shows how spectacular Messier 82 shines in the infrared even though it is relatively puny in both size and mass compared to its big brother, Messier 81,” said Tom Jarrett, a member of the WISE team at the California Institute of Technology in Pasadena.

In this WISE view, infrared light has been color coded so that we can see it with our eyes. The shortest wavelengths (3.4 and 3.6 microns) are shown in blue and blue-green, or cyan, and the longer wavelengths (12 and 22 microns) are green and red. Messier 82 appears in yellow hues because its cocoon of dust gives off longer wavelengths of light (the yellow is a result of combining green and red). This dust is made primarily of polycyclic aromatic hydrocarbons, which are found on Earth as soot.

Messier 81, also known as Bode’s Galaxy, appears blue in the infrared image because it is not as dusty. The blue light is from stars in the galaxy. Knots of yellow seen dotting the spiral arms are dusty areas of recent star formation, most likely triggered by the galaxy’s encounter with its rowdy partner. “It’s striking how the same event stimulated a classic spiral galaxy in Messier 81, and a raging starburst in Messier 82,” said WISE Project Scientist Peter Eisenhardt of NASA’s Jet Propulsion Laboratory in Pasadena, Calif. “WISE is finding the most extreme starbursts across the whole sky, out to distances over a thousand times greater than Messier 82.”

Next time you view M81 and M82, perhaps you’ll see them in a new light?

How To Photograph Space Yourself - Stargazing Live, Preview - BBC Two

New planets are a gas!

The final frontier: Gas worker Peter Jalowiczor is credited with discovering four planets

Published Date: 27 December 2010

By Colin Drury

PETER Jalowiczor is not sure if he believes in extra-terrestrial life.

Which is strange because Peter Jalowiczor has just helped discover a planet around which it may exist.

Quite a claim for a Rotherham gas worker who has never owned a telescope in his life - but a claim which has been confirmed by a team of astronomical experts from the University of California.

For Peter, of Masbrough, has been named by the centre's Lick-Carnegie Planet Search Team as a co-discoverer of four planets known as HD 31253b, HD 218566b, HD177830c and HD 99492c.

It was the hours he spent analysing thousands of figures of space data - all in his spare time, all on his two home PCs - which provided the clues for scientists to establish the existence of the huge gaseous orbs.

"It overwhelms me when I think about it," he says. "I've always been interested in astronomy and I have two science degrees but to be one of the officially recognised finders of these planets is just...I get lost for words."

Here's the science bit: in 2005, astronomers at the university released millions of space measurements collected over several decades and asked enthusiasts to make of them what they would.

Quirks in the data could signify the existence of exoplanets - that is, planets in other solar systems which cannot be seen with even the most powerful telescope because they are so far away.

From March 2007 Peter, 45, spent entire nights reading the data, working the figures, creating graphs.

THE PLANETS IN NUMBERS

HD 31253b - 466 days in its year - 172 light years away

HD 218566b - 225.7 days in its year - 98 light years away

HD177830c - 110.6 days in its year - 190 light years away

HD 99492c - 4,697 days in its year - 58 light years away

"Essentially you're looking for measurements which show a star, which is millions of miles across and light years away, to be oscillating by about 50 metres or less," the father of one explains.

"The measurements are so tiny, it puts many people off looking - even professional astronomers - but I find it fascinating."

He then sent discrepancies he discovered back to the scientists in California where they were further analysed to see if the quirks were caused by the existence of an exoplanet.

NASA's Kepler Mission Discovers Its First Rocky Planet

WASHINGTON -- NASA's Kepler mission confirmed the discovery of its first rocky planet, named Kepler-10b. Measuring 1.4 times the size of Earth, it is the smallest planet ever discovered outside our solar system.

The discovery of this so-called exoplanet is based on more than eight months of data collected by the spacecraft from May 2009 to early January 2010.

"All of Kepler's best capabilities have converged to yield the first solid evidence of a rocky planet orbiting a star other than our sun," said Natalie Batalha, Kepler's deputy science team lead at NASA's Ames Research Center in Moffett Field, Calif., and primary author of a paper on the discovery accepted by the Astrophysical Journal. "The Kepler team made a commitment in 2010 about finding the telltale signatures of small planets in the data, and it's beginning to pay off."

Kepler's ultra-precise photometer measures the tiny decrease in a star's brightness that occurs when a planet crosses in front of it. The size of the planet can be derived from these periodic dips in brightness. The distance between the planet and the star is calculated by measuring the time between successive dips as the planet orbits the star.

Kepler is the first NASA mission capable of finding Earth-size planets in or near the habitable zone, the region in a planetary system where liquid water can exist on the planet's surface. However, since it orbits once every 0.84 days, Kepler-10b is more than 20 times closer to its star than Mercury is to our sun and not in the habitable zone.

Kepler-10 was the first star identified that could potentially harbor a small transiting planet, placing it at the top of the list for ground-based observations with the W.M. Keck Observatory 10-meter telescope in Hawaii.

Scientists waiting for a signal to confirm Kepler-10b as a planet were not disappointed. Keck was able to measure tiny changes in the star's spectrum, called Doppler shifts, caused by the telltale tug exerted by the orbiting planet on the star.

"The discovery of Kepler 10-b is a significant milestone in the search for planets similar to our own," said Douglas Hudgins, Kepler program scientist at NASA Headquarters in Washington. "Although this planet is not in the habitable zone, the exciting find showcases the kinds of discoveries made possible by the mission and the promise of many more to come," he said.

Knowledge of the planet is only as good as the knowledge of the star it orbits. Because Kepler-10 is one of the brighter stars being targeted by Kepler, scientists were able to detect high frequency variations in the star's brightness generated by stellar oscillations, or starquakes. This analysis allowed scientists to pin down Kepler-10b's properties.

There is a clear signal in the data arising from light waves that travel within the interior of the star. Kepler Asteroseismic Science Consortium scientists use the information to better understand the star, just as earthquakes are used to learn about Earth's interior structure. As a result of this analysis, Kepler-10 is one of the most well characterized planet-hosting stars in the universe.

That's good news for the team studying Kepler-10b. Accurate stellar properties yield accurate planet properties. In the case of Kepler-10b, the picture that emerges is of a rocky planet with a mass 4.6 times that of Earth and with an average density of 8.8 grams per cubic centimeter -- similar to that of an iron dumbbell.

Ames manages Kepler's ground system development, mission operations and science data analysis. NASA's Jet Propulsion Laboratory in Pasadena, Calif., managed Kepler mission development.

Ball Aerospace and Technologies Corp. in Boulder, Colo., developed the Kepler flight system and supports mission operations with the Laboratory for Atmospheric and Space Physics at the University of Colorado in Boulder. The Space Telescope Science Institute in Baltimore archives, hosts and distributes the Kepler science data.

Venus and Mercury gleam in the morning sky - Astronomy Magazine

Venus and Mercury gleam in the morning sky - Astronomy Magazine

Orion the Hunter Astronomy Magazine

Orion the Hunter - Free downloadable preview - Astronomy Magazine