Centauri Dreams 24 Apr 2019, 16:59 UTC The transit method has proven invaluable for exoplanet detection, as the runaway success of the Kepler/K2 mission demonstrates. But stars where planets have been detected with this method are still capable of revealing further secrets. Consider Kepler-47. Here we have a circumbinary system some 3340 light years away in the direction of the constellation Cygnus, and as we are now learning about circumbinaries — planets that orbit two stars — the alignment of the orbital plane of the planet is likely to change with time.
astrobites 24 Apr 2019, 16:15 UTC For years now it has been widely held that Mars had an abundance of liquid water in its early history that some scientists believe was removed through an extreme global warming scenario. In 2017 the Mars Reconnaissance Orbiter found evidence of water ice deposits under the poles of Mars. Then in 2018 the Mars Express spacecraft found, using radar, evidence of liquid deep under the ice. Liquid water requires high pressures and temperatures, not believed to be possible on Mars currently, which led the authors of this paper to hypothesize that heating deep under the Martian south pole is responsible for melting the ice.
Chandra X-ray Observatory Blog 24 Apr 2019, 14:46 UTC A neutron star is the compact object formed after a supernova explosion occurring in the late evolutionary stage of a massive star, and it is one of the most mysterious objects in the universe. It is composed of almost all neutrons, and has some extreme physical properties such as ultra-high density and a super-strong magnetic field. It is an excellent natural laboratory for testing basic physical laws. However, up to now, our understanding about the basic properties of neutron stars (e.g., the equation of state, which describes the relation among pressure, density, etc.) is still relatively vague.
Scientific American 24 Apr 2019, 11:00 UTC One of astronomy’s great explainers tells you about the Event Horizon Telescope’s image and plenty more
New Scientist 23 Apr 2019, 19:53 UTC Mars is shaking. NASA’s InSight lander has detected its first marsquake, a rumbling from the planet’s interior, and it may have felt three more. These quakes could help us learn how much water is hiding deep within the planet.
Centauri Dreams 23 Apr 2019, 17:14 UTC About 250 light years away there is a faint object that is on the borderline between brown dwarf and star. Only a tenth of the radius of our Sun, ULAS J224940.13-011236.9 was actually too faint for most telescopes to observe until a huge flare lit it up, turning this L dwarf, among the lowest mass objects that can still be considered a star, 10,000 times brighter than it was before. Very cool compared to the average red dwarf, L dwarfs emit radiation primarily in the infrared.
Starts With a Bang! 23 Apr 2019, 14:01 UTC For most of us here on planet Earth, navigating the world at night is just a little more challenging than during daytime. Without the Sun’s bright light to illuminate our world, our eyes do their best to adapt. Our color-sensing cones move back in our eyes while the monochrome-sensitive rods move forward. Our pupils dilate to larger diameters, letting more light in. Even in the wild, the Moon and stars provide enough light for a sufficiently dark-adapted eye to make out shapes and objects. Evolutionarily, this was a spectacularly useful adaptation. Human vision may be optimally suited to daytime vision, but the ways our eyes adjust also allow us to perceive the Universe far beyond our world. Unfortunately, our connection with the night sky has been severed by a truly human endeavor: artificial lighting. While the benefits to public safety and commerce are inarguable, the tradeoff is unnecessary. Light pollution may a worse problem than ever, but it doesn’t have to be this way.
The Planetary Society Blog 23 Apr 2019, 11:00 UTC Emily Lakdawalla posted an article in February describing challenges facing the Mars Reconnaissance Orbiter and the High Resolution Imaging Science Experiment (HiRISE), based largely on a NASA press release. There were two especially worrisome issues for the HiRISE team and user community: (1) blurred images; and (2) MRO battery issues requiring a future move of MRO’s orbit to a later time of day, leading to lower-quality images. There is now good news about both issues.
NASA Space Station Blog 22 Apr 2019, 16:47 UTC The Expedition 59 crew has been unpacking Northrop Grumman’s Cygnus cargo craft over the weekend and began science operations on the newly delivered space research. The 17thSpaceX Dragon mission is now due to launch next week to replenish the International Space Station.