Category Archives: Astronomy

“So, is that actually about to occur?”

National Geographic: A giant star is acting strange, and astronomers are buzzing. “The red giant Betelgeuse is the dimmest seen in years, prompting some speculation that the star is about to explode. Here’s what we know.”

“[Villanova University’s Edward] Guinan suspects that Betelgeuse is dramatically dimmer now because two of its cycles are overlapping at minimal brightness. In essence, the star is approaching the dimmest points in both its six-year and 425-day cycles, an intersection that makes the star’s normal fluctuations appear much more sinister. After looking through 25 years’ worth of prior data, Guinan suspects that the star will continue to fade for another couple of weeks before gradually turning back on.

But, he says, “if it keeps getting fainter, then all bets are off.“ “

Link via Garret.

“Whoopie! Man, that may have been a small one for Neil, but that’s a long one for me.”

NPR Science: 50 Years Ago, Americans Made The 2nd Moon Landing… Why Doesn’t Anyone Remember?

“Fifty years ago, astronaut Pete Conrad stepped out of the lunar module onto the surface of the moon.

His first words were: “Whoopie! Man, that may have been a small one for Neil, but that’s a long one for me.”

Conrad, who stood at just 5 feet 6 inches tall, was only the third human to set foot on the lunar surface. He did it on November 19, 1969, just four months after Neil Armstrong and Buzz Aldrin made the first lunar landing. However, unlike Armstrong and Aldrin, Conrad and fellow astronaut Alan Bean are not household names.”

I have just one piece of advice: Don’t!

NASA Goddard: NASA’s Guide To Black Hole Safety. (YouTube, 2:39min) “Have you ever thought about visiting a black hole? We sure hope not. However, if you’re absolutely convinced that a black hole is your ideal vacation spot, watch this video before you blast off to learn more about them and (more importantly) how to stay safe.”

Link via Astronomy Picture of the Day.

USA 224

NPR: Amateurs Identify U.S. Spy Satellite Behind President Trump’s Tweet.

“Amateur satellite trackers say they believe an image tweeted by President Trump on Friday came from one of America’s most advanced spy satellites.

The image almost certainly came from a satellite known as USA 224, according to Marco Langbroek, a satellite-tracker based in the Netherlands. The satellite was launched by the National Reconnaissance Office in 2011. Almost everything about it remains highly classified, but Langbroek says that based on its size and orbit, most observers believe USA 224 is one of America’s multibillion-dollar KH-11 reconnaissance satellites.
[…]
Melissa Hanham, a satellite imagery expert and deputy director of the Open Nuclear Network in Vienna, Austria […] says she is amazed a satellite can provide such clear imagery. Spy satellites must peer down through Earth’s atmosphere, which is a bit like trying to look at objects in the bottom of a swimming pool. They also must snap their pictures while whizzing across the sky. Both effects can blur the fine details in images.

“I’m now scratching my head and curious about how they account for the effects of the atmosphere and motion of the objects,” she says.

And she says she thinks she’s not alone. Others will be trying to use the image to learn more about how USA 224 works. “I imagine adversaries are going to take a look at this image and reverse-engineer it to figure out how the sensor itself works and what kind of post-production techniques they’re using,” she says.

Hanham questions whether Trump’s tweet zinging the Iranians was worth the information this image provides to other nations, but she adds: “It’s his decision as the president.””