Space News & Blog Articles

Our most massive satellite galaxy, the Large Magellanic Cloud (LMC), has been the center of a heated debate in the astrophysics community over the last few years. That debate centers on whether this is the LMC’s first or second “pass” by the Milky Way itself - and it has huge implications for the evolution of our galaxy given the disruption such a large grouping of stars has. A new paper from Scott Lucchini, Jiwon Jesse Han, Sapna Mishra, and Andrew J. Fox and his co-authors, currently available in pre-print on arXiv, provides what they claim to be definitive evidence that this is, in fact, the first time LMC has encountered the Milky Way.

Rogue planets sound like rare travelers amongst the stars, freed from the gravitational constraints of a host system, left to forever wander the interstellar void. But modern models suggest these Free Floating Planets (FFPs) as they are technically known, are actually very common - nineteen times more common than planets beyond the “snow line”, which is the distance from the central star where it becomes cold enough that hydrogen compounds like water, ammonia, and methane can condense into ice. But why are FFPs so common? What forces them out of the stellar systems where they form? A new paper from Xiaochen Zheng of the Beijing Planetarium and his co-authors, available in pre-print in arXiv, offers a plausible explanation - planetary “bouncers”.

You’re on the fourth human mission to Mars, and you’re told the Odyssey spacecraft designed to take you there will be the smoothest ride you’ll ever take. It features a newly christened electric propulsion engine which was in the late stages of testing during the first three missions. The mission starts and the spacecraft travels at a crawl, and you wonder if it’s broken. A week goes by and you’re now traveling at more than 400,000 kilometers (250,000 miles) per hour, and your mind is blown as to how fast you’re going, how quickly that happened, and that this mission might be more awesome than you thought.

For the past decade, astronomers thought they had a reasonable answer to that question. Around stars like our Sun, the two dominant planet types are sub-Neptunes, worlds resembling a shrunken Neptune, with thick gaseous envelopes and super-Earths, rocky planets up to ten times the mass of our own. Surveys had found them everywhere, orbiting star after star, and the assumption quietly took hold that these planets must be equally widespread across the Galaxy as a whole.

Studying the thing you can never step outside of and look back at is the fundamental problem facing every cosmologist who has ever looked up at the night sky. The Universe is not a laboratory you can peer into from above, it’s the thing you are already inside. The only way to truly test your ideas about how it works is to build a copy of it, run the clock forward from the Big Bang, and see if what emerges matches what your telescopes are actually telling you.

For most of human spaceflight history, the go to for communications has been radio waves, a technology that has served us remarkably well, but one that is beginning to show its age. When NASA's Artemis II mission carried four astronauts around the Moon in April the year, engineers quietly tested a laser communications terminal that could one day rewrite the rules of deep space exploration.