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Posts Tagged ‘galaxy’

NASA’s NuSTAR Spots Flare from Milky Way’s Black Hole

October 24, 2012 Leave a comment

ScienceDaily (Oct. 23, 2012) — NASA’s newest set of X-ray eyes in the sky, the Nuclear Spectroscopic Telescope Array (NuSTAR), has caught its first look at the giant black hole parked at the center of our galaxy. The observations show the typically mild-mannered black hole during the middle of a flare-up.

NASA’s Nuclear Spectroscopic Telescope Array, or NuSTAR, has captured these first, focused views of the supermassive black hole at the heart of our galaxy in high-energy X-ray light. (Credit: NASA/JPL-Caltech)
 

“We got lucky to have captured an outburst from the black hole during our observing campaign,” said Fiona Harrison, the mission’s principal investigator at the California Institute of Technology (Caltech) in Pasadena. “These data will help us better understand the gentle giant at the heart of our galaxy and why it sometimes flares up for a few hours and then returns to slumber.”

The new images can be seen by visiting: http://www.nasa.gov/nustar .

Read more: http://www.sciencedaily.com/releases/2012/10/121023145224.htm

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Earth-sized planet found just outside solar system

October 17, 2012 Leave a comment

October 16, 2012 by Seth Borenstein

Earth-sized planet found just outside solar systemEnlargeThis artist’s impression shows the planet orbiting the star Alpha Centauri B, a member of the triple star system that is the closest to Earth. Alpha Centauri B is the most brilliant object in the sky and the other dazzling object is Alpha Centauri A. Our own Sun is visible to the upper right. The tiny signal of the planet was found with the HARPS spectrograph on the 3.6-metre telescope at ESO’s La Silla Observatory in Chile. Credit: ESO/L. Calçada

(Phys.org)—European astronomers have discovered a planet with about the mass of the Earth orbiting a star in the Alpha Centauri system—the nearest to Earth. It is also the lightest exoplanet ever discovered around a star like the Sun. The planet was detected using the HARPS instrument on the 3.6-metre telescope at ESO’s La Silla Observatory in Chile. The results will appear online in the journal Nature on 17 October 2012.

Alpha Centauri is one of the brightest in the southern skies and is the nearest stellar system to our Solar System—only 4.3 light-years away. It is actually a triple star—a system consisting of two stars similar to the Sun orbiting close to each other, designated Alpha Centauri A and B, and a more distant and faint red component known as Proxima Centauri. Since the nineteenth century astronomers have speculated about orbiting these bodies, the closest possible abodes for life beyond the Solar System, but searches of increasing precision had revealed nothing. Until now.

Read more: http://phys.org/news/2012-10-earth-sized-planet-solar.html

Large water reservoirs at the dawn of stellar birth

October 15, 2012 Leave a comment

Large water reservoirs at the dawn of stellar birth

Herschel’s infrared view of part of the Taurus Molecular Cloud, within which the bright, cold pre-stellar cloud L1544 can be seen at the lower left. It is surrounded by many other clouds of gas and dust of varying density. The Taurus Molecular Cloud is about 450 light-years from Earth and is the nearest large region of star formation. The image covers a field of view of approximately 1 x 2 arcminutes. Credit: ESA/Herschel/SPIRE

ESA’s Herschel space observatory has discovered enough water vapour to fill Earth’s oceans more than 2000 times over, in a gas and dust cloud that is on the verge of collapsing into a new Sun-like star.

Stars form within cold, dark clouds of gas and dust – ‘pre-stellar cores’ – that contain all the ingredients to make solar systems like our own.

Water, essential to life on Earth, has previously been detected outside of our Solar System as gas and ice coated onto tiny dust grains near sites of active star formation, and in proto-planetary discs capable of forming alien planetary systems.

The new Herschel observations of a cold pre- in the constellation of Taurus known as Lynds 1544 are the first detection of water vapour in a molecular cloud on the verge of star formation.

More than 2000 Earth oceans-worth of water vapour were detected, liberated from icy dust grains by high-energy cosmic rays passing through the cloud.

Large water reservoirs at the dawn of stellar birth

Read more: http://phys.org/news/2012-10-large-reservoirs-dawn-stellar-birth.html

Awesome death spiral of a bizarre star

October 11, 2012 Leave a comment

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The name of this thing is AFGL 3068. It’s been known as a bright infrared source for some time, but images just showed it as a dot. This Hubble image using the Advanced Camera for Surveys reveals an intricate, delicate and exceedingly faint spiral pattern. It’s so faint no one has ever detected it before!

So what’s going on here? First off, this is not a spiral galaxy! It’s a binary star*, two stars that orbit each other, located about 3000 light years away from us. One of the stars is what’s called a carbon star, similar to the Sun but much older. The Sun is still happily fusing hydrogen into helium in its core, but older stars run out of available hydrogen. Eventually, they fuse helium into carbon. When this happens the star swells up and becomes a red giant (note: that’s the brief version; the actual events are a tad more complicated).

Read more:
http://blogs.discovermagazine.com/badastronomy/2010/09/06/awesome-death-spiral-of-a-bizarre-star/

WISE survey uncovers millions of black holes


 

WISE survey uncovers millions of black holes

 
 

 

 

 

 

 

 

 

 

With its all-sky infrared survey, NASA’s Wide-field Infrared Survey Explorer, or WISE, has identified millions of quasar candidates. Image credit: NASA/JPL-Caltech/UCLA

(Phys.org)—NASA’s Wide-field Infrared Survey Explorer (WISE) mission has led to a bonanza of newfound supermassive black holes and extreme galaxies called hot DOGs, or dust-obscured galaxies.

Images from the telescope have revealed millions of dusty black hole candidates across the universe and about 1,000 even dustier objects thought to be among the brightest ever found. These powerful galaxies, which burn brightly with infrared light, are nicknamed .

“WISE has exposed a menagerie of hidden objects,” said Hashima Hasan, WISE program scientist at NASA Headquarters in Washington. “We’ve found an asteroid dancing ahead of Earth in its orbit, the coldest star-like orbs known and now, supermassive black holes and galaxies hiding behind cloaks of dust.”

WISE scanned the whole sky twice in infrared light, completing its survey in early 2011. Like night-vision goggles probing the dark, the telescope captured millions of images of the sky. All the data from the mission have been released publicly, allowing astronomers to dig in and make .

Read more: http://phys.org/news/2012-08-wise-survey-uncovers-millions-black.html

 

Milky Way Now Has a Twin (or Two): Astronomers Find First Group of Galaxies Just Like Ours


ScienceDaily (Aug. 22, 2012) — Research presented Aug. 23, 2012 at the International Astronomical Union General Assembly in Beijing has found the first group of galaxies that is just like ours, a rare sight in the local Universe.

This image shows one of the two ‘exact matches’ to the Milky Way system found in the survey. The larger galaxy, denoted GAMA202627, which is similar to the Milky Way clearly has two large companions off to the bottom left of the image. In this image bluer colours indicate hotter, younger, stars like many of those that are found in our galaxy. (Credit: Dr. Aaron Robotham, ICRAR/St Andrews using GAMA data)
 

The Milky Way is a fairly typical galaxy on its own, but when paired with its close neighbours — the Magellanic Clouds — it is very rare, and could have been one of a kind, until a survey of our local Universe found another two examples just like us.

Astronomer Dr Aaron Robotham, jointly from the University of Western Australia node of the International Centre for Radio Astronomy Research (ICRAR) and the University of St Andrews in Scotland, searched for groups of galaxies similar to ours in the most detailed map of the local Universe yet, the Galaxy and Mass Assembly survey (GAMA).

“We’ve never found another galaxy system like the Milky Way before, which is not surprising considering how hard they are to spot! It’s only recently become possible to do the type of analysis that lets us find similar groups,” says Dr Robotham.

Read more: http://www.sciencedaily.com/releases/2012/08/120822221342.htm

Hubble sees the needle galaxy, edge-on and up close


July 16, 2012

Hubble sees the needle galaxy, edge-on and up close

 

 

 

 

 

 

 

 

 

Image credit: ESA/NASA

This image snapped by the NASA/ESA Hubble Space Telescope reveals an exquisitely detailed view of part of the disc of the spiral galaxy NGC 4565. This bright galaxy is one of the most famous examples of an edge-on spiral galaxy, oriented perpendicularly to our line of sight so that we see right into its luminous disc. NGC 4565 has been nicknamed the Needle Galaxy because, when seen in full, it appears as a very narrow streak of light on the sky.

The edgewise view into the Needle Galaxy shown here looks very similar to the view we have from our into the core of the Milky Way. In both cases ribbons of dust block some of the light coming from the galactic disc. To the lower right, the dust stands in even starker contrast against the copious yellow light from the star-filled central regions. NGC 4565’s core is off camera to the lower right.

Read more : http://phys.org/news/2012-07-hubble-needle-galaxy-edge-on.html