Are dreams affected by microgravity? How do you exercise in space? What's that on Chris Hadfield's forehead?
These were among the questions posed to NASA astronauts -- three of whom are orbiting 240 miles above the Earth, from the International Space Station (ISS) -- during NASA's first live Google Hangout.
Astronauts Kevin Ford, Chris Hadfield and Tom Marshburn answered questions from the International Space Station, while NASA astronaut Ron Garan and Nicole Stott fielded questions from the ground. Questions were submitted live and through social media using the #askastro tag. You can watch the discussion above or on NASA's Google Plus page.
Here are some of the gems delivered by the astronauts during the chat:
In space, astronauts can turn like falling cats by twisting their bodies. They see shooting stars below them from the space station, but no satellites. Space, says Canadian Space Agency's Hadfield, is so deep black "it almost has a texture when you look at it."
And in orbit, gravity causes blood to shift upward through the body toward the head, resulting in puffy faces and skinny legs. With extended time in space, the heart shrinks, as it pumps less blood. This interesting physiological phenomenon about living in space came from NASA astronaut Nicole Stott. "For some people, this happens more significantly than others," Stott said. "Some feel congested. That happens and it kind of mellows out after a while."
As for exercise, astronauts aboard the ISS use the on-board treadmill and stationary bikes to do an hour of aerobics and an hour of weightlifting every day to keep their muscles strong.
Coming home and readjusting to gravity is a challenge, Stott said, adding that upon return, she felt like she weighed 500 pounds.
But nothing, Garan added, compares to the feeling of being back home. He recalls landing in Kazakhstan.
"I remember looking out that window and seeing grass and flowers and thinking, 'We're home.' Even if we're in Kazakhstan, home is Earth," he said.
And as for the object seen on Hadfield's forehead: it's a temperature probe that measures his body's circadian rhythm. He has another probe over his heart.
QUICK BITES
Miles O'Brien hosted a live chat Thursday evening about his PBS NOVA documentary and NewsHour report, Mind of a Rampage Killer. You can view that entire chat here. The most important thing he learned from the story, he revealed: "that licking a rat baby makes them nicer rat adults."
You can Miles' NOVA documentary here, his NewsHour report here, and extended coverage online.
Watch VideoFor example, the video and full transcript of his phone conversation with Andy Williams, who, at age 15, shot two people and wounded 13 at his high school in Santee, California. That was in 2001. And here's his gripping interview with Liza Long, the blogger who wrote "I am Adam Lanza's Mother" on the roots of rage:
Watch VideoWatch eruptions from Mount Etna live.
Also on the NewsHour this week, news from a new archaeological find in the Orkney Islands off the northern tip of Scotland. Jeffrey Brown reports on what's known of the discovery, including how the site might have been part of one of the biggest barbecues in history.
Watch VideoSound like a bird? Darwin once wrote that sounds uttered by birds "offered in several respects the nearest analogy to language." Now MIT researchers hypothesize that bird song indeed might be a critical part of the combination that triggered hyman speech.
Still on birds, this year's Great Backyard Bird Count shattered all records: more than 25 million birds, that's 3138 species and nearly one-third of the total bird species were counted. From Newswise.
What did Earth look like 250 million years ago? Or 4.5 billion years ago? Check out this new app from the Howard Hughes Medical Institute.
NOT SAFE FOR LUNCH
When you walk into a library and get a whiff of that old book smell, what you're really sniffing is book decay. The British Library and a chemical detection company known for bomb detection are seeking to chemically analyze that smell. Acidic or non-acidic paper? Acid hydrolysis or oxidation? Pop Sci reports.Rebecca Jacobson, Patti Parson and David Pelcyger contributed to this report.