Gravitational waves were predicted by Einstein's theory of general relativity in 1916, and now, almost exactly 100 years later, the faint ripples across space-time have been found. The advanced Laser Interferometric Gravitational-wave Observatory (aLIGO) has achieved the first direct measurement.
Astronomers discovered stars may not accumulate their final mass steadily, as was previously thought, but in a series of violent events manifesting themselves as sharp stellar brightening. The young FU Orionis star in the constellation of Orion is the prototype example, which showed an increase in brightness by a factor of 250 over a time period of just one year, staying in this high-luminosity state now for almost a century.
Bursts of gamma rays from the center of our galaxy are not likely to be signals of dark matter but rather other astrophysical phenomena such as fast-rotating stars called millisecond pulsars, according to two new studies.
The moon was formed by a violent, head-on collision between the early Earth and a 'planetary embryo' called Theia approximately 100 million years after the Earth formed, geochemists and colleagues report.
Hubble Space Telescope astronomers are finding that the old adage 'what goes up must come down' even applies to an immense cloud of hydrogen gas outside our Milky Way galaxy. The invisible cloud is plummeting toward our galaxy at nearly 700,000 miles per hour.
An international team of researchers has found for the first time that the connection between a galaxy cluster and surrounding dark matter is not characterized solely by the mass of clusters, but also by their formation history.
The beginning of the cosmos is cloaked and hidden from the view of our most powerful telescopes. Yet observations we make today can give clues to the universe's origin. New research suggests a novel way of probing the beginning of space and time to determine which of the competing theories is correct.
Researchers have found evidence of a giant planet tracing a bizarre, highly elongated orbit in the outer solar system. The object, which the researchers have nicknamed Planet Nine, has a mass about 10 times that of Earth and orbits about 20 times farther from the sun on average than does Neptune.
Right now, astronomers are viewing a ball of hot gas billions of light years away that is radiating the energy of hundreds of billions of suns. At its heart is an object a little larger than 10 miles across. And astronomers are not entirely sure what it is.