Centauri Dreams 17 Jul 2018, 17:16 UTC A cluster of stars sharing a common origin, now gravitationally unbound, is referred to as a stellar association. I’ve written before about how useful some of these groupings can be. In the form of so-called moving groups — a stellar association that is still somewhat coherent — they help us identify stars of similar age, an aid as we discover new objects. Now we have word of an object called 2MASS 0249 c, found in the Beta Pictoris moving group, that has striking similarities to the most famous member of that group, Beta Pictoris b.
The Guardian 17 Jul 2018, 14:01 UTC One of a dozen new moons discovered around Jupiter is circling the planet on a suicide orbit that will inevitably lead to its violent destruction, astronomers say. Researchers in the US stumbled upon the new moons while hunting for a mysterious ninth planet that is postulated to lurk far beyond the orbit of Neptune, the most distant planet in the solar system.
Astro Bob 16 Jul 2018, 20:50 UTC Last night, we had a chance to see one of the finest conjunctions of the year. The moon and Venus looked incredible together. I happened to catch sight of the crescent just before sundown with Venus already bright and obvious 1½° to its left. Nearby, cirrus clouds caught the last solar rays and glowed with intense scarlet and coral hues. 10 minutes later the colors had drained away, leaving the duo entangled in gray wisps.
Centauri Dreams 16 Jul 2018, 16:42 UTC We learned late last week that the near-Earth asteroid 2017 YE5, discovered just last December, is what is described as an ‘equal mass’ binary. This would make it the fourth near-Earth asteroid binary ever detected in which the two objects are nearly identical in size, both about 900 meters. The binary’s closest approach to Earth was on June 21, 2017, when it came to within 6 million kilometers, some 16 times the distance between the Earth and the Moon. It won’t be that close again for at least another 170 years.
Starts With a Bang! 16 Jul 2018, 14:01 UTC With some 400 billion stars burning steadily, the Milky Way is just a typical galaxy in the Universe.
Astronomy Now 16 Jul 2018, 13:00 UTC Researchers using different techniques to measure how fast the universe is expanding have come up with two different answers, a conflict that so far has resisted explanation. Researchers at the Massachusetts Institute of Technology say the conflict may be resolved by analysis of gravitational waves from neutron star-black hole mergers, resulting in a value for the Hubble constant, a measure of the Universe’s expansion, that is more precise than earlier results.
EarthSky Blog 15 Jul 2018, 10:03 UTC The object known as 1I/2017 U1 (and nicknamed ‘Oumuamua) was traveling too fast (196,000 miles per hour, that’s 54 miles per second or 87.3 kilometers per second) to have originated in our solar system. Comets and asteroids from within our solar system move at a slower speed, typically an average of 12 miles per second (19 km per second) . In non-technical terms, ‘Oumuamua is an interstellar vagabond.
io9 Space 13 Jul 2018, 17:00 UTC You’re looking at the center of our galactic home, the Milky Way, as imaged by 64 radio telescopes in the South African wilderness. Scientists released this image today to inaugurate the completed MeerKAT radio telescope. But these scopes form part of an even more ambitious project: the Square Kilometer Array, a joint effort to build the world’s largest telescope, spanning the continents of Africa and Australia.
Starts With a Bang! 13 Jul 2018, 14:01 UTC Perhaps the greatest quest in science today is to find life that originated beyond Earth. While searches for extraterrestrial intelligence have all come up empty, and our astronomical capabilities have not quite advanced to the stage where we can sniff it out in the atmospheres of planets around other stars, there’s a close-to-home possibility to consider. If one of the worlds in our Solar System contains life — past or present — we can discover it with today’s technology. Many possibilities abound for where life might exist today, including beneath the surface of Mars, in the cloud-tops of Venus, and in the sub-surface ocean of a world like Jupiter’s moon, Europa. But one world in the Solar System stands out: Saturn’s moon Enceladus. With a liquid water ocean beneath its ice and geysers that shoot off hundreds of miles above the surface, the possibility of encountering alien life has never been more accessible.