Gravity, one of the four fundamental forces of nature, appears reassuringly constant across the universe, according to a decades-long study of a distant pulsar. This research helps to answer a long-standing question in cosmology: Is the force of gravity the same everywhere and at all times? The answer, so far, appears to be yes.
This extraordinary bubble, glowing like the ghost of a star in the haunting darkness of space, may appear supernatural and mysterious, but it is a familiar astronomical object: a planetary nebula, the remnants of a dying star. This is the best view of the little-known object ESO 378-1 yet obtained and was captured by ESO’s Very Large Telescope in northern Chile.
A dying star’s final moments are captured in this image of planetary nebula NGC 6565 in Sagittarius from the NASA/ESA Hubble Space Telescope. The death throes of this star may only last mere moments on a cosmological timescale, but this star’s demise is still quite lengthy by our standards, lasting tens of thousands of years.
Observations with the Atacama Large Millimetre/submillimetre Array (ALMA) have revealed what seems to be a gigantic flare on the surface of Mira, one of the closest and most famous red giant stars in the sky. Activity like this in red giants — similar to what we see in the Sun — comes as a surprise to astronomers.
Type Ia supernovae are violent stellar explosions that shine as some of the brightest objects in the universe, but there are still many mysteries surrounding their origin. Now a team of astronomers have witnessed a supernova smashing into a nearby star, shocking it, and creating an ultraviolet glow that reveals the size of the companion.