Scott Alan Johnston, Author at Universe Today

July 18, 2022July 20, 2022 by Scott Alan Johnston

Betelgeuse and Antares Have Been Observed for Over 2,000 Years. Astronomers can use This to Figure out how old They are

Stars don’t usually evolve fast enough for humans to notice them change within one lifetime. Even a hundred lifetimes won’t do – astronomical processes are just too slow. But not always. There are some phases of stellar evolution that happen quickly, and when they do, they can be tracked. A new paper posted to ArXiv last week uses astronomical observations found in ancient Roman texts, medieval astronomical logs, and manuscripts from China’s Han Dynasty to trace the recent evolution of several bright stars, including red supergiant Antares, and Betelgeuse: one of the most dynamic stars in our sky. With observations from across the historical record, the paper suggests that Betelgeuse may have just recently passed through the ‘Hertzsprung gap,’ the transitional phase between a main sequence star and its current classification as a red supergiant.

July 1, 2022July 1, 2022 by Scott Alan Johnston

The Solar System is Stable for at Least the Next 100,000 Years

It’s nice to have a feel-good story every once in a while, so here’s one to hold off the existential dread: the Earth isn’t likely to get flung off into deep space for at least 100,000 years. In fact, all of the Solar System’s planets are safe for that time frame, so there is good news all around, for you and your favorite planetary body.

June 26, 2022June 26, 2022 by Scott Alan Johnston

Remember That Rocket That was Going to Crash Into the Moon? Scientists Think They've Found the Crater

The Lunar Reconnaissance Orbiter (LRO) – NASA’s eye-in-the-sky in orbit around the Moon – has found the crash site of the mystery rocket booster that slammed into the far side of the Moon back on March 4th, 2022. The LRO images, taken May 25th, revealed not just a single crater, but a double crater formed by the rocket’s impact, posing a new mystery for astronomers to unravel.

June 19, 2022June 20, 2022 by Scott Alan Johnston

Once Again, Galaxies Look Surprisingly Mature Shortly After the Beginning of the Universe

A young galaxy with the catchy, roll-off-the-tongue name A1689-zD1 has experts in galactic formation talking. Recent observations show that this galaxy, seen as it would have looked just 700 million years after the Big Bang, is larger than initially believed, with significant outflows of hot gas from its core, and a halo of cold gas emanating from its outer rim. A1689-zD1 is considered representative of young ‘normal’ galaxies (as opposed to ‘massive’ galaxies), and the new observations suggest that the adolescence of normal galaxies may be more rambunctious than previous models suggest.

May 24, 2022May 24, 2022 by Scott Alan Johnston

Spacesuits are Leaking Water and NASA is Holding off any Spacewalks Until They can Solve the Problem

NASA’s spacesuits are getting old. The extra-vehicular mobility units – EMUs for short – were designed and built for spacewalks outside NASA’s space shuttles, which flew for the last time in 2011. Nowadays, the EMUs are an integral part of maintaining and upgrading the International Space Station (ISS) exterior, providing the crew with the ability to live and work in the vacuum of space for extended periods of time (spacewalks regularly last from 6 to 8 hours). However, at the end of the most recent spacewalk on March 23, NASA astronaut Kayla Barron discovered water in the helmet of German astronaut Matthias Maurer while she helped him remove the suit.

May 15, 2022May 15, 2022 by Scott Alan Johnston

Cosmic Rays can Help Keep the World's Clocks in Sync

The world has a robust, accurate timekeeping system that regulates our clocks. Humanity uses it for everything we do, from our financial systems to satellite navigation, computer and phone networks, and GPS. But the current system is not perfect, and has vulnerabilities to cyber-attack and disruption. Given the importance of accurate timekeeping to our society (as a fundamental underpinning of life in the 21st century), experts are always looking for ways to improve the system and add redundancy. Researchers at the University of Tokyo have taken a big step in this direction, developing a new method of time synchronization that takes advantage of cosmic rays to calibrate the world’s clocks.

May 11, 2022May 11, 2022 by Scott Alan Johnston

‘The Clocks are Telling Lies:’ A New Book from Universe Today Writer Scott Alan Johnston

Scott Alan Johnston (that’s me!) joined the Universe Today team just over a year ago. Since then, I’ve written over 50 space news stories for the website – time flies when you’re having fun! But when I’m not writing articles here on Universe Today, I’m a historian of science, and I recently released a new book about the history of timekeeping.

Have you ever wondered why we tell time the way we do? Well, history buffs, come along for a journey:

May 8, 2022May 8, 2022 by Scott Alan Johnston

Even Stars Doomed to Die as Supernovae can Have Planets

90 percent of all exoplanets discovered to date (there are now more than 5000 of them) orbit around stars the same size or smaller than our sun. Giant stars seem to lack planetary companions, and this fact has serious implications for how we understand solar system formation. But is the dearth of planets around large stars a true reflection of nature, or is there some bias inherent in how we look for exoplanets that is causing us to miss them? The recent discovery of two gas giants orbiting a giant star called µ2 Scorpii suggests it might be the latter.

May 1, 2022May 1, 2022 by Scott Alan Johnston

China is Building an Asteroid Deflection Mission of its own, due for Launch in 2025

Illustration of the DART spacecraft with the Roll Out Solar Arrays (ROSA) extended. Credit: NASA

There’s an old joke that the dinosaurs are only extinct because they didn’t develop a space agency. The implication, of course, is that unlike our reptilian ancestors, we humans might be able to save ourselves from an impending asteroid strike on Earth, given our six-and-a-half decades of spaceflight experience. But the fact is that while we have achieved amazing things since Sputnik kicked off the space age in 1957, very little effort thus far has gone into developing asteroid deflection technologies. We are woefully inexperienced in this arena, and aside from our Hollywood dramatizations of it, we’ve never yet put our capabilities to the test. But that’s about to change.

April 23, 2022April 24, 2022 by Scott Alan Johnston

NASA is Ready to try and fix Lucy’s Unlatched Solar Panel

NASA’s Lucy spacecraft, currently on its way to the outer Solar System to study Jupiter’s Trojan asteroids, has a solar panel problem. Shortly after its launch last October, engineers determined that one of Lucy’s two solar panels failed to open completely. While the spacecraft has enough power to function, the team is concerned about how the unlatched panel might hinder Lucy’s performance going forward. In an attempt to fix the problem, the team will carry out a new procedure next month that is designed to unfurl the solar panel the rest of the way, and latch it firmly in place.