Galactic ‘Natural Laboratory’ Helps Work Out Space Distance Measuring Techniques
Image of spiral galaxy UGC 9391 taken by Hubble Space Telescope’s Wide Field Camera 3
The galaxy in question features two distinct types of light sources – Cepheid variable stars and a supernova – thus providing scientists with means to “improve their distance estimates.”Researchers operating the Hubble Space Telescope have unveiled a photo of a distant spiral galaxy that may help astronomers measure distances to the more remote celestial bodies out there.Designated UGC 9391, the galaxy in question resides in the Draco constellation, some 130 million light years away.The image of the galaxy was released late last month and is part of a set of observations performed by the space telescope, which astronomers used in the creation of the so-called “Cosmic Distance Ladder” – a “set of connected measurements” expected to help gauge how far some of the more distant objects in space actually are.As European Space Agency explained in a statement accompanying the galaxy’s image, distance in space can only be directly measured for objects located roughly 3,000 light years away. For the celestial bodies that lie even farther away, astronomers have to “rely on a set of measured correlations calibrated against nearby objects.”
Science & TechNew 3D Model of Cat’s Eye Nebula Hints at Its ‘Binary Star’ Past8 October, 10:01 GMTWhat makes UGC 9391 so handy is the fact that this galaxy light sources such as Cepheid variable stars and a supernova, thus providing researchers with “a natural laboratory in which to compare two measuring techniques” and helping them “improve their distance estimates.”“Improving the precision of distance measurements helps astronomers quantify how quickly the universe is expanding – one of Hubble’s key science goals,” the space agency noted.
