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Venice Update

News of Venice, CA and Marina del Rey CA

Rare High-Resolution of Exploded Star

Courtesy of W.M. Keck Observatory

Courtesy of W.M. Keck Observatory

Note: This is a press release from W.M. Keck Observatory.

Bob Eklund Looking Up

Bob Eklund
Looking Up

Scientists will now be able to measure how fast the universe is truly expanding with the kind of precision not possible before.

This, after an international team of astronomers led by Stockholm University, Sweden, captured four distinct images of a gravitationally lensed Type Ia supernova, named iPTF16geu.

To get a high-resolution view, the discovery team used the W. M. Keck Observatory’s OSIRIS and NIRC2 instruments with laser-guided adaptive optics at near-infrared wavelengths.

This discovery is highly interesting to scientists because Type Ia supernovas can be used as a “standard candle” to calculate galactic distances.

A standard candle is an astrophysical object that emits a certain, known amount of light. In this case, the object is a Type Ia supernova, a class of dying stars that always explode with the same absolute brightness. If astronomers know such an object’s true luminosity, they can infer its distance from Earth. The dimmer the object, the farther away it is.

This rare discovery is made possible through gravitational lensing, a phenomenon that was first predicted by Albert Einstein in 1912. As light of the distant object passes by a massive object such as a galaxy cluster in the foreground, it gets bent by gravity, just as light gets bent passing through a lens. When the foreground object is massive enough, it will magnify the object behind it. In iPTF16geu’s case, its light was magnified by up to 50 times and bent into four separate images by a galaxy in front of it.

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