Posted on by Scott Alan Johnston

To Fight Climate Change, We Could Block the Sun. A Lightweight Solar Sail Could Make it Feasible

Can we build an enormous umbrella to dim the Sun? Such a feat would be a megaproject on a scale like no other. It would take at least 400 dedicated rocket launches a year, for ten years (There have been 172 rocket launches by all nations so far in 2022). The project would weigh in at 550,000 tons: at its lightest. And it would be an ecological experiment that puts us all – the entire planet – in the petri dish, with high risk and high reward. But could such a project actually reverse climate change and bring us back from the brink of global disaster?

The answer seems to be yes, it could work. But there are consequences, and with the planet at stake, it seems wise to examine them before committing to such a thing.

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Posted on by Scott Alan Johnston

Construction Begins on the Square Kilometer Array

Artist's Impression of SKA-Low. credit: SKAO/DISR

At twin ground-breaking ceremonies today in South Africa and Australia, project leaders formally marked the start of construction on what will be the largest radio telescope ever built. Dubbed the Square Kilometer Array Observatory (SKAO) – referring to the total area the antennas and dishes will cover when complete – the telescope is not a single detector but rather a collection of them, connected across two continents using a technique known as interferometry (the same technique used by the Event Horizon Telescope, which took the first ever photograph of a black hole in 2019).

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Posted on by Scott Alan Johnston

One of the World's Biggest Radio Telescopes is Hunting for Signals From Extraterrestrial Civilizations

Breakthrough Listen, a privately funded project seeking evidence of extraterrestrial intelligence, has started operations on the MeerKAT radio telescope array in South Africa. Over the next two years, the team will search over a million nearby stars, expanding the number of targets observed by a factor of 1000.

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Posted on by Scott Alan Johnston

The First SLS Launch Caused Damage to the Launch Pad. How bad was it?

When you test launch the most powerful rocket ever successfully flown, there’s bound to be some collateral damage. With 8.8 million pounds of thrust at liftoff, NASA’s Space Launch System (SLS) packs a mighty punch (the Saturn V, which carried astronauts to the moon in 1969, produced 7.5 million pounds). After November 16’s test flight of SLS, dubbed Artemis I, the pad was a little worse for wear, but not outside of expected parameters, NASA officials say.

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Posted on by Scott Alan Johnston

The X-37B is Back After 908 Days in Orbit. What was it Doing up There? That's Classified

At 5:22 AM Eastern Time on November 12, the Space Force’s (and Air Force’s) X-37B spaceplane landed back on Earth after two and a half years in orbit. The secretive spaceplane has now performed 6 missions, and the latest, OTV-6, was the longest flight yet. Details about the X-37B’s purpose are scarce, though it is clear that the vehicle is designed to serve as a testbed for advanced spaceflight capabilities. Here’s what we know about the latest mission.

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Posted on by Scott Alan Johnston

Planets Make it Harder to Figure out a Star’s age

Active star, nearby exoplanet, and inactive companion star for NASA's Chandra X-ray Observatory. 2022

Estimating stellar age has always been a challenge for astronomers. Now, a certain class of exoplanets is making the process even more complicated. Hot Jupiters – gas giants with orbital periods smaller than that of Mercury – appear to have an anti-aging effect on their stars, according to a new study. These enormous planets inflict both magnetic and tidal interference on their host star, speeding up the star’s rotation and causing them to emit X-rays more energetically, both of which are hallmarks of stellar youth. The result calls into question some of what we previously believed about stellar age, and offers a glimpse at the ongoing interconnectivity between a star and its planets long after their formation.

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