Lights in the Dark 20 Jul 2018, 21:41 UTC This dramatic image, a color-composite I made from raw data captured by NASA’s Juno spacecraft, shows a bright band of high-altitude clouds on Jupiter’s northern hemisphere on July 16, 2018. Because of the abstract nature of Jupiter’s atmosphere in general (and a fun little phenomenon called pareidolia) one could find many different shapes in this view, but to me the band of clouds is reminiscent of a thick, twisted bath towel getting wrung dry.
Scientific American 20 Jul 2018, 17:00 UTC Most likely, this is the best-known picture of a flag ever taken: Buzz Aldrin standing next to the first U.S. flag planted on the Moon. For those who knew their world history, it also rang some alarm bells. Only less than a century ago, back on Earth, planting a national flag in another part of the world still amounted to claiming that territory for the fatherland. Did the Stars and Stripes on the moon signify the establishment of an American colony? When people hear for the first time that I am a lawyer practicing and teaching something called “space law,” the question they ask most frequently, often with a big smile or a twinkle in the eye, is: “So tell me, who owns the moon?”
Astrobiology Magazine 20 Jul 2018, 16:00 UTC Current techniques tend to only detect exoplanets with short orbital periods, however a new method developed by UNIGE researchers allows to find within months planets with periods lasting several years.
Starts With a Bang! 20 Jul 2018, 14:01 UTC The science of planet-hunting has truly taken off in the 21st century, with the transit method leading the way. When a planet passes in front of its parent star, relative to our line-of-sight, some of the star’s light will disappear for a short while. These transits are a prolific method for exoplanet hunters to search for worlds around other stars. As of today, we know of thousands of stars with worlds around them, and most of them were discovered by transit. When you design a mission optimized to look for planets, you expect that the technique is going to uncover a few oddities. But nothing prepared astronomers for the oddball that is Tabby’s star, whose flux dims by a tremendous amount, without any regularly repeating signals. After years of speculation involving scenarios ranging from comet storms to alien megastructures, scientists have finally solved the mystery. Dust, in an entirely new way, looks to be the culprit.
Starts With a Bang! 19 Jul 2018, 14:01 UTC One of the great mysteries in science is determining not only what’s out there, but what creates the signals we detect here on Earth. For over a century, we’ve known that zipping through the Universe are cosmic rays: high energy particles originating from far beyond our galaxy. While some sources for these particles have been identified, the overwhelming majority of them, including the ones that are most energetic, remain a mystery. As of today, all of that has changed. The IceCube collaboration, on September 22, 2017, detected an ultra-high-energy neutrino that arrived at the South Pole, and was able to identify its source. When a series of gamma-ray telescopes looked at that same position, they not only saw a signal, they identified a blazar, which happened to be flaring at that very moment. At last, humanity has discovered at least one source that creates these ultra-energetic cosmic particles.
Many Worlds 18 Jul 2018, 17:08 UTC The first exoplanets were all found using the radial velocity method of measuring the “wobble” of a star — movement caused by the gravitational pull of an orbiting planet. Radial velocity has been great for detecting large exoplanets relatively close to our solar system, for assessing their mass and for finding out how long it takes for the planet to orbit its host star. But so far the technique has not been able to identify and confirm many Earth-sized planets, a primary goal of much planet hunting. The wobble caused by the presence of a planet that size has been too faint to be detected by current radial velocity instruments and techniques. However, a new generation of instruments is coming on line with the goal of bringing the radial velocity technique into the small planet search. To do that, the new instruments, together with their telescopes. must be able to detect a sun wobble of 10 to 20 centimeters per second. That’s quite an improvement on the current detection limit of about one meter per second.
Starts With a Bang! 18 Jul 2018, 14:01 UTC When we look out at the Universe today, we see that it’s full of stars and galaxies, in all directions and at all locations in space. The Universe isn’t static, though; the distant galaxies are bound together in groups and clusters, with those groups and clusters speeding away from one another as part of the expanding Universe. As the Universe expands, it gets not only sparser, but cooler, as the individual photons shift to redder wavelengths as they travel through space. But this means if we look back in time, the Universe was not only denser, but also hotter. If we go all the way back to the earliest moments where this description applies, to the first moments of the Big Bang, we come to the Universe as it was at its absolute hottest. Here’s what it was like to live back then.
Scientific American 18 Jul 2018, 11:00 UTC Times sure change. A little over two decades ago, the discovery of a new extrasolar planet was invariably treated as front-page news. In recent years, a newly discovered world elicits barely a mention, and simply adds another data point to the thousands of planetary confirmations that are accumulating in NASA’s Exoplanet Archive. Like many fields of endeavor, exoplanetology is transitioning to the realm of big data.