Showing posts with label Light. Show all posts
Showing posts with label Light. Show all posts

Sunday, July 31, 2011

Peace In The Light… An Orion Sunset

NGC 2023 - Credit: ESA/Hubble & NASA

Here the stellar winds are carving out a cavity in a vast reflection nebula. It’s an area of Orion that many of us have seen before – but not like the Hubble Space Telescope reveals it. Located right next door to the famous Horsehead Nebula, NGC 2023 can be glimpsed in a telescope as a tiny patch of light that closely resembles its more famous cousin – the Orion Nebula. Spanning approximately four light years across and located some 1500 light-years from Earth, this awesome visage conjures up a peaceful picture of the setting Sun.

However, there’s no sun slipping beyond a horizon in NGC 2023. Hidden inside is a hot, newborn star illuminating the dusty cloud of gas which is its womb. Radiation pressure runs rampant from this massive young B-type star hidden just outside the edge of this image – its winds blowing the material away from it and forming the fanciful shapes we see. Caught in the act are young proto-stars awaiting their turn to be born.

Unlike our Earthly clouds, the clouds we see here are 5000 times denser than the interstellar medium. It is here where weird green clumps could be Herbig-Haro objects – the product of high-speed gases impacting the diaphanous material and creating shockwaves. Their lives are short – lasting only a few thousand years – but what an image they create! If only they could sing…

“I can’t light no more of your darkness… All my pictures seem to fade to black and white…I’m growing tired and time stands still before me… Frozen here on the ladder of my life.”

Original Story Source: Hubble News Photo Release.


View the original article here

Saturday, June 18, 2011

Black Hole Devours Star and Hurls Energy Across 3.8 Billion Light Years

What University of Warwick researchers think the star may have looked like at the start of its disruption by a black hole at the center of a galaxy 3.8 billion light years distant resulting in the outburst known as Sw 1644+57. Credit: University of Warwick / Mark A. Garlick

Engaging the Hubble Space Telescope, Swift satellite and the Chandra X-ray Observatory, astronomers at the University of Warwick were quick to pick up a signal from Swift’s Burst Alert Telescope on March 28, 2011. In a classic line from Easy Rider, Jack Nicholson says: “It’s a UFO beaming back at you.” But this time it isn’t a UFO… it’s the death scream of a star being consumed by a black hole. The alert was just the beginning of a series of x-ray blasts that turned out to be the largest and most luminous event so far recorded in a distant galaxy.

Originating 3.8 billion light years from Earth in the direction of the constellation of Draco, the beam consisting of high energy X-rays and gamma-rays remained brilliant for a period of weeks after the initial event. As more and more material from the doomed star crossed over the event horizon, bright flares erupted signaling its demise. Says Dr. Andrew Levan, lead researcher on the paper from the University of Warwick; “Despite the power of this the cataclysmic event we still only happen to see this event because our solar system happened to be looking right down the barrel of this jet of energy”.

Dr Andrew Levan is a researcher at the University of Warwick.

Dr. Levan’s findings were published today in the Journal Science in a paper entitled “An Extremely Luminous Panchromatic Outburst from the Nucleus of a Distant Galaxy”. His findings leave no doubt as to the origin of the event and it has been cataloged as Sw 1644+57.

“The only explanation that so far fits the size, intensity, time scale, and level of fluctuation of the observed event, is that a massive black at the very centre of that galaxy has pulled in a large star and ripped it apart by tidal disruption.” says Levan. “The spinning black hole then created the two jets one of which pointed straight to Earth.”

And straight into our eager eyes…

Original Story Source: Eurekalert.


View the original article here