In the remaining days of October and early into November, a fascinating series of planetary peregrinations plays out low in the East before dawn twilight gets too bright. Venus, like a sprinter on the inside lane of a running track, overtakes both Jupiter in Mars in two readily observable conjunctions set against the stellar backdrop of constellations Leo and Virgo.
When a star comes too close to the intense gravity of black hole, the resulting tidal forces can rip the star apart. In these so-called tidal disruptions, some of the stellar debris is flung outward at high speeds, while the rest falls toward the black hole, causing a distinct X-ray flare that can last for years. A team of astronomers has observed a tidal disruption event in galaxy PGC 043234 that lies about 290 million light-years from Earth.
Astronomers have compiled the largest astronomical image to date. The picture of the Milky Way contains 46 billion pixels and was compiled from 268 individual images over a period of five years. More than 50,000 new variable objects have been discovered by the researchers so far and an online tool is available to navigate the image, or search for specific objects.
The Death Star of the movie Star Wars may be fictional, but planetary destruction is real. Astronomers announced today that they have spotted a large, rocky object disintegrating in its death spiral around a distant white dwarf star. The discovery also confirms a long-standing theory behind the source of white dwarf “pollution” by metals.
Using ESO’s Very Large Telescope, an international team of astronomers have found the hottest and most massive double star with components so close that they touch each other. The two stars in the extreme system VFTS 352 could be heading for a dramatic end, during which the two stars either coalesce to create a single giant star, or form a binary black hole.
For more than 30 years, scientists have argued about a controversial hypothesis relating to periodic mass extinctions and impact craters on Earth caused by comet and asteroid showers. Now scientists conclude that these events show a cyclical pattern over the studied period, with both impacts and extinction events taking place every 26 million years.
The highlight of October for meteor observers is the Orionid meteor shower, which occurs when the Earth encounters the debris stream of Halley’s Comet. With a broad maximum 21-23 October, peak rates are typically about a quarter of those seen for the Perseids of August. A good percentage of Orionids are bright and leave persistent trains.
Earth came early to the party in the evolving universe. According to a new theoretical study, when our solar system was born 4.6 billion years ago only eight percent of the potentially habitable planets that will ever form in the universe existed. And, the party won’t be over when the Sun burns out in another 6 billion years. The bulk of those planets — 92 percent — have yet to be born.
Astronomers studying the birth of planetary systems in the young (about 2-3 million years old) star forming region IC348 in Perseus as seen by the infrared cameras onboard the Spitzer Space Telescope have found thirteen stars in this complex with detectable discs, none of which is as massive as our early solar system’s disc.
One of the most important but least understood processes in astronomy is accretion, where the mass of an object grows by gravitationally collecting material from nearby. Now an international team has discovered that that the process by which astronomical objects grow is fundamentally the same, regardless of the type, mass or size of the object.
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