Researchers measure distance to nearest galaxy
Researchers have managed to accurately measure the distance to Earth's nearest neighboring galaxy, the Large Magellanic Cloud (LMC), which was one of the biggest mysteries of the universe. Consequently, at the same time researchers have recalibrated the astronomical calculation that helps measure the expansion of the universe.
Astronomers typically use a fundamental quality, the Hubble constant, which measures the current rate at which our universe is expanding. The measurement component is named after 20th Century astronomer Edwin Hubble. Hubble is touted for concluding that the Universe has been growing constantly since its inception.
However, one of the largest uncertainties from the Hubble constant was using this fundamental quality to measure the distance between us and the LMC. Surprisingly, the LMC actually orbits our own Milky Way.
"Because the LMC is close and contains a significant number of different stellar distance indicators, hundreds of distance measurements using it have been recorded over the years," said Carnegie's Ian Thompson in a statement "Unfortunately; nearly all the determinations have systemic errors, with each method carrying its own uncertainties."
The astronomers found the distance to the LMC by observing rare pairs of stars, known as eclipsing binaries. These stars are gravitationally bound to each other, and once per orbit, each star eclipses its partner.
Researchers tracked these changes, and found that by measuring the orbital speeds of the stars, they could work out how big they are, as well as find out other information about their orbits. They were also able to calculate accurate distances based on the brightness of the stars.