Starts With a Bang! 19 Jun 2018, 14:01 UTC We know what our Solar System looks like today, but one of science’s greatest mysteries is how it formed and grew up to be the way it is right now. There are some general pieces we know must be true from a variety of astronomical observations. Like all star systems, ours formed from a collapsing cloud of molecular gas. Like all stars with planets, our young proto-star formed a protoplanetary disk that grew into planets, asteroids, and the Kuiper belt. From simulations, we know that many bodies were ejected, accreted, and absorbed over time. But 4.5 billion years on, we don’t have remnants of what our Solar System was like at the time of its birth. In the great gravitational dance taking place in our cosmic backyard, we cannot know what our full history was. All we have left are the survivors. But for the first time, those survivors likely include something left over from our protoplanetary dawn: interplanetary dust particles. For the first time, we can truly learn where we came from.
Astro Bob 18 Jun 2018, 22:11 UTC Venus met up with the crescent moon over the weekend. Tonight through Wednesday, it gets cozy with the Beehive star cluster in Cancer the Crab. To see it you have to wait until later in twilight when Venus will be rather low in the western sky and use binoculars. Focus on Venus and look to its left for the star cluster.
Planetaria 18 Jun 2018, 19:58 UTC With the discovery of thousands of exoplanets orbiting other stars, the search for life elsewhere has entered an exciting new phase. So far, most of these worlds have been found many light-years away (largely due to the fact that the Kepler Space Telescope, which has discovered the majority of them so far, has focused on a specific patch of sky which contains very distant stars). But what about closer stars? Including, of course, Alpha Centauri, the closest star system to our Sun, only just over four light-years away. According to Tom Ayres of the University of Colorado Boulder: “Because it is relatively close, the Alpha Centauri system is seen by many as the best candidate to explore for signs of life. The question is, will we find planets in an environment conducive to life as we know it?”
Astrobiology Magazine 18 Jun 2018, 13:34 UTC A little stream in the south of England could guide the way towards finding evidence for ancient life on Mars, in the form of fatty acids preserved in an iron-rich mineral called goethite. Researchers from Imperial College London ventured to the county of Dorset on the UK’s south-coast to sample an acidic stream running into St Oswald’s Bay, which is close to the famous Durdle Door limestone rock formation. The acidity of the stream, which has a pH of 3.5, is believed to be similar to water that flowed on early Mars during its Hesperian epoch over three billion years ago.
Many Worlds 15 Jun 2018, 16:20 UTC Just as the number of planets discovered outside our solar system is large and growing — more than 3,700 confirmed at last count — so too is the number of ingenious ways to find exoplanets ever on the rise. The first exoplanets were found by measuring the “wobble” in their host stars caused by the gravitational pull of the planets, then came the transit technique that measured dips in the light from stars as planets passed in front of them, followed by the direct imaging of moving objects deemed to be planets, and numerous more. A new technique can now be added to the toolkit, one that is useful only in specific galactic circumstances but is nonetheless ingenious and intriguing.
Astronomy Now 15 Jun 2018, 14:31 UTC Wolf-Rayet stars are massive, high-energy suns near the end of their lives, pumping out thick, fast-moving stellar winds that can create vast bubbles in space as they ram into the cooler interstellar medium. Shockwaves heat up any gas in the region, occasionally to temperatures high enough to produce X-rays. But it is a relatively rare phenomenon, and only three such Wolf-Rayet stars have been found. This one, WR18, has extremely powerful winds, and once it exhausts its nuclear fuel it likely will explode in a supernova blast. This image was captured by the European Space Agency’s XMM-Newton space telescope. Hot X-ray emitting gas is shown in blue with yellow-green oxygen and red sulphur emissions are seen in optical wavelengths.
NASA Space Station Blog 14 Jun 2018, 19:01 UTC Expedition 56 Commander Drew Feustel and Flight Engineer Ricky Arnold of NASA completed the sixth spacewalk at the International Space Station this year at 2:55 p.m. EDT, lasting 6 hours, 49 minutes. The two astronauts installed new high-definition cameras that will provide enhanced views during the final phase of approach and docking of the SpaceX Crew Dragon and Boeing Starliner commercial crew spacecraft that will soon begin launching from American soil.