Two NASA space telescopes have teamed up to identify, for the first time, the detailed chemical "fingerprint" of a planet between the sizes of Earth and Neptune. No planets like this can be found in our own solar system, but they are common around other stars.
Alpha Centauri is the closest star system to us, at 4.37 light-years (about 25 trillion miles) away. In 2016, astronomers discovered an exoplanet orbiting one of the three stars in the Alpha Centauri system. Spurred on by that discovery, the European Southern Observatory (ESO) has developed a new instrument to find any other planets that might be in the Alpha Centauri system, and it’s busy looking right now.
On May 25th, 2019, a strange, double-asteroid (1999 KW4) flew past Earth at a distance and speed that is likely to make a lot of people nervous. As always, there was no danger, since the asteroid passed Earth at a minimum distance of 5.2 million km (3.23 million mi), over 15 times greater than the distance between Earth of the Moon, and its orbit is well-understood by scientists.
There’s a lot going on at the center of our galaxy. A supermassive black hole named Sagittarius A-Star resides there, drawing material in with its inexorable gravitational attraction. In that mind-bending neighborhood, where the laws of physics are stretched beyond comprehension, astronomers have detected a ring of cool gas.
In June of 2017, NASA’s Neutron Star Interior Composition Explorer (NICER) was installed aboard the International Space Station (ISS). The purpose of this instrument is to provide high-precision measurements of neutron stars and other super-dense objects that are on the verge of collapsing into black holes. NICER is also be the first instrument designed to test technology that will use pulsars as navigation beacons.
Like most planets in our solar system, the Earth has its own magnetic field. Thanks to its largely molten iron core, our planet is in fact a bit like a bar magnet. It has a north and south magnetic pole, separate from the geographic poles, with a field connecting the two. This field protects our planet from radiation and is responsible for creating the northern and southern lights – spectacular events that are only visible near the magnetic poles.
In 1960, famed theoretical physicist Freeman Dyson made a radical proposal. In a paper titled “Search for Artificial Stellar Sources of Infrared Radiation” he suggested that advanced extra-terrestrial intelligences (ETIs) could be found by looking for signs of artificial structures so large, they encompassed entire star systems (aka. megastructures). Since then, many scientists have come up with their own ideas for possible megastructures.
The constellation of Orion (The Hunter) is one of the most recognisable collections of stars in the night sky. We have noted Orion’s prominent stars for tens of thousands of years at least, and likely far longer. Chinese astronomers called it 参宿 or Shēn, literally “three stars”, for its three bright dots (which form the Hunter’s belt). The ancient Egyptians regarded it as the gods Sah and Sopdet, manifestations of Osiris and Isis, respectively, whereas Greek astronomers saw a brave hunter — the eponymous Orion — with his sword above his head, ready to strike.
NASA's Spitzer Space Telescope has revealed that some of the universe's earliest galaxies were brighter than expected. The excess light is a byproduct of the galaxies releasing incredibly high amounts of ionizing radiation. The finding offers clues to the cause of the Epoch of Reionization, a major cosmic event that transformed the universe from being mostly opaque to the brilliant starscape seen today.