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Gravitational Lensing Provides Rare Glimpse Into Interiors of Black Holes Article written: 17 Aug , 2017 by Matt Williams The observable Universe is an extremely big place, measuring an estimated 91 billion light-years in diameter. As a result, astronomers are forced to rely on powerful instruments to see faraway objects. But even these are sometimes limited, and must be paired with a technique known as gravitational lensing. This involves relying on a large distribution of matter (a galaxy or star) to magnify the light coming from a distant object.Using this technique, an international team led by researchers from the California...

Astronomers want to harness [the Sun's] spacetime-warping gravity as a lens to image the surface of exoplanets in astonishing detail The bluish ring is a distant galaxy whose image has been magnified and warped by the gravity of a reddish galaxy in the foreground Credit: ESA/Hubble & NASA Wikimedia Within just a few years, astronomers may at last find a planet that shows signs of life as we know it, in the form of atmospheric gases that betray signs of biological activity. This would be a transformational event for our civilization. But, what would we do next? How could we...

Gravitational Lensing in Proxima Planet Hunt by Paul Gilster on June 4, 2013 I normally think about gravitational lensing as a way of finding planets that are a long way from home. That’s just the nature of the beast: Lensing as an exoplanet detection tool depends upon a star with planets moving in front of a background object, its mass ‘bending’ space enough to cause slight changes to the image of the farther star. Monitor those changes closely enough and you may see the signature of a second disruption, flagging the presence of a planet around the closer star. Occultations...

A Deep-Sky Look at Lensing by Paul Gilster on January 13, 2011 As we continue to investigate the parameters of the proposed FOCAL mission to the SunÂ’s gravitational lens, itÂ’s worth recalling how the idea of lensing has taken hold in recent decades. Einstein noted the possibilities of such lensing as far back as 1936, but it wasnÂ’t until 1964 that Sydney Liebes (Stanford University) worked out the mathematical theory, explaining how a galaxy between the Earth and an extremely distant object like a quasar could focus the latterÂ’s light in ways that should be detectable by astronomers. And...

A FOCAL Mission into the Oort Cloud by Paul Gilster on November 15, 2010 After all this time, IÂ’m still trying to wrap my head around the idea of massive objects in space as lenses, their distortion of spacetime offering the ability to see distant objects at huge magnification. On Friday we saw how the lensing effect caused by galactic clusters can be used to study dark energy. And consider the early results from the Herschel-ATLAS project, conducted by ESAÂ’s Herschel Space Observatory. Herschel is scanning large areas of the sky in far-infrared and sub-millimeter light. Many of its...

Astronomy Picture of the Day Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. 2003 January 8 Abell 1689 Warps Space Credit: N. Benitez (JHU), T. Broadhurst (Hebrew Univ.), H. Ford (JHU), M. Clampin(STScI), G. Hartig (STScI), G. Illingworth (UCO/Lick), ACS Science Team, ESA, NASA Explanation: Two billion light-years away, galaxy cluster Abell 1689 is one of the most massive objects in the Universe. In this view from the Hubble Space Telescope's Advanced Camera for Surveys, Abell 1689 is seen to warp...

Astronomy Picture of the Day Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. 2002 September 8 Too Close to a Black Hole Credit & Copyright: Robert Nemiroff (MTU) Explanation: What would you see if you went right up to a black hole? Above are two computer generated images highlighting how strange things would look. On the left is a normal star field containing the constellation Orion. Notice the three stars of nearly equal brightness that make up Orion's Belt. On the...