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Showing posts with label Gravity. Show all posts
Showing posts with label Gravity. Show all posts

Tuesday, October 8, 2013

'Gravity': Science vs. fiction

Warner Bros. Pictures

1 How Real Is This Orbital Blockbuster? Warner Bros. Pictures

2 Orbital Debris Causes … Complications Warner Bros. Pictures

3 Houston ... We Have a Good One For You Warner Bros. Pictures

4 Can You Steal a Space Capsule? Warner Bros. Pictures

5 Correct Use of Jargon is Critical Warner Bros. Pictures

6 Remember to Use Sunscreen (SPF 900) Warner Bros. Pictures

Warner Bros. Pictures

8 When The Comsat Grid Goes Down, Try Ham Radio Warner Bros. Pictures

Warner Bros. Pictures

Director Alfonso Cuarón's visually stunning film "Gravity," in theaters today, is already being heralded as one of the year's best movies. Sandra Bullock and George Clooney star as astronauts whose mission goes spectacularly wrong when a cloud of orbital debris shreds their shuttle, cuts off communication and leaves them stranded in space.

These details have already been revealed in the film's trailers, but what the previews can't convey is the impressive sense of authenticity and verisimilitude that director Cuarón brings to the big screen. Thanks to a brilliant visual design and strategic use of 3-D effects, the movie feels like being in space.

That sense of authenticity also applies to the film's depiction of the specifics of an actual NASA space mission. It's clear that the filmmakers did their homework. The movie is careful to stay within the realm of plausibility demanded by the genre of hard science fiction.

But just to be sure, we asked former NASA astronaut Leroy Chiao -- a veteran of three shuttle missions, four space walks and a six-month stint on the International Space Station -- to help us separate the science from the fiction.

Warning: Several significant plot spoilers dead ahead

Warner Bros. Pictures

The crisis in the film is precipitated when the Russians blow up one of their own satellites, triggering a chain reaction that sends a cloud of lethal debris toward our heroes at around, oh, 17,000 mph. Chiao says the dangers of such a scenario are quite real and have been studied extensively.

"Just in recent history, the Chinese conducted an anti-weapons satellite test," Chiao says. "They blew up one of their old weather satellites, which created a bunch of debris."

Could such an incident really set off a chain-reaction that wipes out everything in orbit?

"It's not implausible, but it's unlikely," Chiao says. "Of course, if you have orbital debris, it can damage satellites or other spacecraft and potentially cause them to break up in turn. But the thing is, satellites are actually spaced pretty far apart. To get a cascade or chain reaction is pretty unlikely."

Science Movies to Avoid on Date Night

Warner Bros. Pictures

Before everything goes haywire in orbit, the spacewalking astronauts Ryan Stone (Bullock) and Matt Kowalski (Clooney) keep it loose by casually chatting, joking with ground control in Houston and even listening to music. Is it really that casual up in space?

"Yeah, during spacewalks we're tied in with Houston and tied in with the crew inside (the shuttle), of course," Chiao says. "We have some light-hearted moments and we joke around a bit."

BLOG: Huge Space Battle Rumbles Virtual Universe

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When the debris cloud destroys the astronauts' ride back home -- that is to say, the space shuttle -- Stone is forced to improvise by breaking into an old Soyuz spacecraft docked at the International Space Station. Chiao says such orbital grand theft is quite possible, but pretty tricky.

"In order to open the outer door of the airlock you have to have the inner hatch closed and the air evacuated in between," Chaio says. "On the American airlock, you could open the pressure equalization valves, and there's a handle outside so you could definitely open the outer hatch. But the trick is, on the inside, the crew would have to have already closed that inner hatch. Otherwise you let all the air out of the station. If the crew configured it that way before they abandoned ship, then yes that could happen. It's physically possible."

The Science and Fiction of ‘Oblivion’

Warner Bros. Pictures

After the orbital debris cascade knocks out communication satellites, Stone and Kowalski lose contact with ground control. They keep transmitting, though, in hopes that someone is listening. Each message begins with the rather haunting phrase, "Transmitting in the blind..."

"Yeah, that's real phraseology and that's used in aircraft operations also," Chiao says. "You call 'in the blind' if you're not receiving them, but you think they might be receiving you. You're basically letting them know that you're not able to hear them."

Warner Bros. Pictures

In one rather pretty scene, astronaut Stone ditches the spacesuit and catches her breath in a pressurized space vehicle, as sunlight streams in through a nearby porthole. But without a spacesuit or, say, the ozone layer, isn't dangerous to be exposed to direct sunlight in orbit?

"It depends on the window, but most windows are treated with UV protection," Chiao says. "For example, on the shuttle, all the windows had UV protection coatings on them. On the station, in the Russian segment, the small windows generally did not have UV protection, so they would be more optically pure. You'd get a pretty severe sunburn if you were in direct sunlight through one of those windows."

Into Reality: Top Star Trek Warp Speed Concepts

Warner Bros. Pictures

In fact, Stone uses the porthole sunlight to do a little light reading. Improvising inside Russian and Chinese spacecraft, she's able to get systems working by, apparently, reading the user manuals handily stored nearby. Really? You can fire up a spacecraft by reading the manual?

Surprisingly, Chiao says this is fairly accurate: "There are definitely paper procedures and books, certainly in the Soyuz and, I imagine, the Chinese spacecraft as well," Chiao says. "On the shuttle we had paper books. The problem would be, having not been trained, she may not know how to follow the instructions. She might not even know the language. But the books are there, and they're definitely used."

Chiao, by the way, would be prepared in such a situation: He speaks both Chinese and Russian.

Astronaut Gave 'Gravity' Advice To Sandra Bullock

Warner Bros. Pictures

A fairly relentless thriller, "Gravity" is short on light moments, but one of them occurs when Stone tries to raise ground control on a complex communications matrix … and gets a giddy Chinese farmer on ham radio. According to Chiao, that absolutely could happen, and has.

"On both the shuttle and ISS, we're normally going through satellites, but we have backup ways of communicating that are more direct-line," Chiao says. "We have a UHF radio that could go direct to the ground sites. The normal S-band radios can also go to ground sites. Just because you lose the satellites doesn't mean you lose comm."

And ham radio?

"Sure, on board the station we do have a ham radio and that's one way we organize conference sessions with schools and students," Chiao says. "As we fly from horizon to horizon, line-of-sight, we're able to answer questions for about 10 minutes or so. In fact, I remember hearing truck drivers talking to each other while we were over rural China. I tried calling down to them but they couldn't hear me."

VIDEO: What It's Like To Be An Astronaut

Warner Bros. Pictures

As the film's beginning title cards read, there's no oxygen in space, no air pressure, no sound. Life in space is impossible. The spacewalking sequences, in particular, underline just how vulnerable astronauts are.

Chiao says the trick is not to think about it too much. "You know, I've wanted to do this since I was a little kid, so getting into orbit and looking out that window for the first time was just such an emotional moment."

"Doing a spacewalk is a little different," Chiao says. "You're acutely aware that you're at higher risk. You're not protected by a pressure vessel and a spacecraft hull. If something goes wrong, your buddies inside, there's very little they can do to help you. It's a heightened sense of awareness. You're very careful and deliberate. You're always checking the tethers because the worst thing that could happen is you get unattached...."

Science vs. Fiction: 'Elysium'


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Wednesday, August 17, 2011

NASA Primes Twin Moon Gravity Probes for September Launch (SPACE.com)

Jason Rhian, SPACE.com Contributor
Space.com Jason Rhian, Space.com Contributor
space.com – 1 hr 2 mins ago

CAPE CANAVERAL, Fla. — A set of twin lunar probes are gearing up for a planned September launch to the moon,  with NASA set to attach the spacecraft duo to their rocket soon.

The twin Gravity Recovery and Interior Laboratory spacecraft (nicknamed GRAIL) are poised to launch moonward on Sept. 8 from the Cape Canaveral Air Force Base here.

The GRAIL mission is designed to discover details of the moon's gravity field from the inside out. The twin probes will fly in tandem to scan the lunar crust to the core, in hopes of collecting measurements for the most accurate gravitational map of the moon ever produced.

"Unlike many other planetary missions GRAIL consists of two spacecraft which are mirror images of one another," said Sami Asmar a member of the GRAIL science team. "So they cannot be interchanged or switched and they will fly together in formation transmitting radio information between the two spacecraft – this allows us to peer into the moon from the core to the crust." [Photos: Our Changing Moon]

Cleaning up for the moon

The GRAIL probes are currently being housed in a clean room near NASA's Kennedy Space Center here. Anyone who enters the ultra-clean facility is required to wear a protective white jumpsuit, sometimes referred to as a "bunny suit."

This head-to-toe outer layer leaves only the eyes exposed, but it is just the first precautionary tier in a multi-layered system designed to keep the spacecraft clean before it is sent to our nearest celestial neighbor.

All camera equipment brought in to photograph the twin GRAIL spacecraft must be cleaned under the supervision of specially trained contamination-control specialists, and strict rules govern what type of equipment can be brought into the facility. These regulations extend even to pens and paper — no conventional writing utensils are allowed inside the clean room, since ordinary paper can carry particles that could clog vital systems on the spacecraft in the microgravity environment of space.

Shoot for the moon

Grail is slated to launch from Launch Complex 17-B at Cape Canaveral Air Force Station on Sept. 8 at 8:37 a.m. EDT (1237 GMT). The two probes will ride on a Delta 2 rocket, in what will be the final launch of a Delta 2 from the Air Force-run spaceport.

After the probes lift off, the journey to the moon will last about 3 1/2 months. After that, the science mission is set to last for a total of 90 days. GRAIL is similar to the Gravity Recovery and Climate Experiment or GRACE mission which launched in 2002 and made detailed measurements of Earth's gravity field. [Infographic: Inside Earth's Moon]

 "GRAIL will have a trans-lunar cruise of about three-and-a-half months, they will arrive at the moon on New Year’s Eve 2012," said Bruce Reid, the mission's launch service provider manager.  "Once there they will completely map the gravity of the moon. This is important for not only future missions, but to also provide us with a better understanding other terrestrial planets.”

The GRAIL science team is made up of a number of scientists, including former NASA astronaut Sally Ride, who is assisting with the project’s public outreach efforts.

GRAIL is the second of three NASA missions launching over the next few months to explore the solar system.

On Aug. 5, NASA launched the Juno spacecraft toward Jupiter. It will take the probe five years to reach the gas giant planet.

NASA's newest Mars rover, the Mars Science Laboratory Curiosity, is currently scheduled to launch in late November.

Follow SPACE.com for the latest in space science and exploration news on Twitter @Spacedotcom and on Facebook.


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