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A supermassive black hole in action

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Copyright NASA, ESA, S. Baum & C. O’Dea (RIT), R. Perley & W. Cotton (NRAO/AUI/NSF), and the Hubble Heritage Team (STScI/AURA)

Copyright NASA, ESA, S. Baum & C. O’Dea (RIT), R. Perley & W. Cotton (NRAO/AUI/NSF), and the Hubble Heritage Team (STScI/AURA)

Scientists often use the combined power of multiple telescopes to reveal the secrets of the Universe – and this image is a prime example of when this technique is strikingly effective.

The yellow-hued object at the centre of the frame is an elliptical galaxy known as Hercules A, seen by the Earth-orbiting NASA/ESA Hubble Space Telescope. In normal light, an observer would only see this object floating in the inky blackness of space.

However, view Hercules A with a radio telescope, and the entire region is completely transformed. Stunning red–pink jets of material can be seen billowing outwards from the galaxy – jets that are completely invisible in visible light. They are shown here as seen by the Karl G. Jansky Very Large Array radio observatory in New Mexico, USA. These radio observations were combined with the Hubble visible-light data obtained with the Wide Field Camera 3 to create this striking composite.

The two jets are composed of hot, high-energy plasma that has been flung from the centre of Hercules A, a process that is driven by a supermassive black hole lurking at the galaxy’s heart. This black hole is some 2.5 billion times the mass of the Sun, and around a thousand times more massive than the black hole at the centre of our Milky Way galaxy.

Hercules A’s black hole heats material and accelerates it to nearly the speed of light, sending it flying out into space at phenomenally high speeds. These highly focused jets lose energy as they travel, eventually slowing down and spreading out to form the cloud-like lobes seen here.

The multiple bright rings and knots seen within these lobes suggest that the black hole has sent out numerous successive bursts of material over the course of its history. The jets stretch for around 1.5 million light-years – roughly 15 times the size of the Milky Way.

Hercules A, also known as 3C 348, lies around two billion light-years away. It is one of the brightest sources of radio emission outside our Galaxy.

This image was originally published in November 2012.

Read more at www.esa.int

Written by physicsgg

November 18, 2015 at 1:46 pm

Posted in ASTRONOMY, ASTROPHYSICS

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Oxymoronic Black Hole Provides Clues to Growth

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A Sloan Digital Sky Survey image of RGG 118, a galaxy containing the smallest supermassive black hole ever detected. The inset is a Chandra image showing hot gas around the black hole. Credits: NASA/CXC/Univ of Michigan/V.F.Baldassare, et al; Optical: SDSS

A Sloan Digital Sky Survey image of RGG 118, a galaxy containing the smallest supermassive black hole ever detected. The inset is a Chandra image showing hot gas around the black hole.
Credits: NASA/CXC/Univ of Michigan/V.F.Baldassare, et al; Optical: SDSS

Astronomers using NASA’s Chandra X-ray Observatory and the 6.5-meter Clay Telescope in Chile have identified the smallest supermassive black hole ever detected in the center of a galaxy. This oxymoronic object could provide clues to how larger black holes formed along with their host galaxies 13 billion years or more in the past.

Astronomers estimate this supermassive black hole is about 50,000 times the mass of the sun. This is less than half the mass of the previous smallest black hole at the center of a galaxy. Read the rest of this entry »

Written by physicsgg

August 11, 2015 at 6:46 pm

Posted in ASTRONOMY, ASTROPHYSICS

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Gravitational Constant Appears Universally Constant, Pulsar Study Suggests

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The NSF's Robert C. Byrd Green Bank Telescope, part of the National Radio Astronomy Observatory. Credit: NRAO/AUI/NSF

The NSF’s Robert C. Byrd Green Bank Telescope, part of the National Radio Astronomy Observatory. Credit: NRAO/AUI/NSF

Gravity, one of the four fundamental forces of nature, appears reassuringly constant across the Universe, according to a decades-long study of a distant pulsar. This research helps to answer a long-standing question in cosmology: Is the force of gravity the same everywhere and at all times? The answer, so far, appears to be yes.

Astronomers using the National Science Foundation’s (NSF) Green Bank Telescope (GBT) in West Virginia and its Arecibo Observatory in Puerto Rico conducted a 21-year study to precisely measure the steady “tick-tick-tick” of a pulsar known as PSR J1713+0747. This painstaking research produced the best constraint ever of the gravitational constant measured outside of our Solar System. Read the rest of this entry »

Written by physicsgg

August 8, 2015 at 12:26 pm

Posted in ASTRONOMY, ASTROPHYSICS

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Tidal Stripping Simulation

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Animation showing the formation of an ultra-dense galaxy: the giant host galaxy disrupts the smaller galaxy, removing its fluffy outer parts, and the dense center is left behind. The animation then zooms in to a possible embedded planet and supermassive black hole.

Written by physicsgg

August 4, 2015 at 10:43 am

Posted in ASTRONOMY, ASTROPHYSICS

Stellar Music

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The Multiperiodic Pulsating Star Y Cam A as a Musical Instrument

Burak Ulas
In this study we generate musical chords from the oscillation frequencies of the primary component of oscillating eclipsing Algol system Y Cam. The parameters and the procedure of the musical chord generation process from the stellar oscillations are described in detail. A musical piece is also composed in appropriate scale for Y Cam A by using the generated chords from the results of the asteroseismic analysis of the stellar data. The music scores and the digital sound files are provided for both the generated chords and the musical composition. Our study shows that the further orchestral compositions can be made from the frequency analysis results of several pulsating stars by using the procedure stated in present study.
Read more at http://arxiv.org/pdf/1507.07307v1.pdf

Written by physicsgg

August 2, 2015 at 2:03 pm

At What Distance Can the Human Eye Detect a Candle Flame?

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Kevin Krisciunas, Don Carona
Using CCD observations of a candle flame situated at a distance of 338 m and calibrated with observations of Vega, we show that a candle flame situated at ~2.6 km (1.6 miles) is comparable in brightness to a 6th magnitude star with the spectral energy distribution of Vega. The human eye cannot detect a candle flame at 10 miles or further, as some statements on the web suggest…
Read more at http://arxiv.org/ftp/arxiv/papers/1507/1507.06270.pdf

Written by physicsgg

July 26, 2015 at 11:52 pm

Posted in ASTRONOMY

Pluto’s Moons are Tumbling into Chaos

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Written by physicsgg

July 8, 2015 at 10:36 pm

Posted in ASTRONOMY, SPACE

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Kepler’s Second Law of Motion

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Written by physicsgg

June 11, 2015 at 5:12 am

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