Centauri Dreams 11 Jun 2020, 14:35 UTC Finding out that Titan is migrating away from Saturn should cause little surprise. Our own Moon moves away from the Earth at about 38 millimeters per year (even as Earth’s rotation slows ever so slightly, lengthening the day by 23 microseconds every year). Titan’s gravitational pull on Saturn causes frictional processes inside the giant world that ultimately impart energy to Titan, moving it away from its host in a similar way. The surprise attendant to a new paper on this phenomenon is the size of the movement, about 100 times greater than had been expected.
Bad Astronomy 11 Jun 2020, 13:00 UTC This story starts over 20 years ago, when a pair of astronomers decided to map a large chunk of the sky using essentially a nice telephoto camera equipped with a filter that picks out the light from warm hydrogen gas in space. Gas like that preferentially emits light in the red part of the spectrum (at a wavelength 0.656 microns, if you like geeky numbers) so using a filter centered there blocks out a lot of extraneous light, letting faint hydrogen become visible.
Bad Astronomy 10 Jun 2020, 13:00 UTC In the premier episode of Star Trek: The Next Generation, "Encounter at Farpoint", the Enterprise has to solve a mystery at a distant planet — which turns out to be (spoilers!) that the inhabitants of the planet have been holding a huge space-faring jellyfish-like creature captive. At the end of the episode, after Picard and crew save it, the creature flies up into space, meeting its mate in orbit, and they entwine long tentacles as they (presumably joyfully) reunite. This episode premiered in 1987. Why bring it up now? Because maybe Captain Picard should've checked the historical records. If he had found old 21st century observations of the galaxy ESO 137-006, the mystery would've been solved a lot faster. But then, a different mystery would've taken its place.
Lights in the Dark 9 Jun 2020, 16:27 UTC As it sped away from Venus, NASA’s Mariner 10 spacecraft captured this seemingly peaceful view of a planet the size of Earth, wrapped in a dense, global cloud layer. But, contrary to its serene appearance, the clouded globe of Venus is a world of intense heat, crushing atmospheric pressure and clouds of corrosive acid.
Universe Today 9 Jun 2020, 13:10 UTC Most people with any interest in astronomy know about the Crab Nebula. It’s a supernova remnant in the constellation Taurus, and its image is all over the place. Google “Hubble images” and it’s right there with other crowd favorites, like the Pillars of Creation.
Lights in the Dark 8 Jun 2020, 19:04 UTC Three new views of the Martian moon Phobos have been captured by NASA’s Mars Odyssey orbiter. Taken this past winter and this spring, they capture the moon as it drifts into and out of Mars’ shadow. Combined with three previous images, these observations represent waxing, waning and full views of Phobos and show how the moon warms and cools.
Starts With a Bang! 8 Jun 2020, 14:01 UTC Maybe 100% of stars don’t have planets, after all.
Universe Today 5 Jun 2020, 15:36 UTC In the standard model of cosmology, dark energy fills the universe. It causes the universe to expand at an ever-increasing rate, and it makes up more than 70% of the cosmos. But there’s a problem. When we measure the rate of cosmic expansion in different ways, we get results that disagree with each other.