Marshall works on astronauts' radiation shield

The Birmingham News ^ | 16 Jan 2004 | Kent Faulk

[demlosers]

HUNTSVILLE - Scientists at the Marshall Space Flight Center are working on a key problem of sending people on long-term trips into space - protecting them from dangerous doses of radiation.

When President Bush announced a new quest to go back to the moon and eventually on to Mars, he noted the dangers space-travelers will face.

"The environment of space is hostile to human beings," Bush said. "Radiation and weightlessness pose dangers to human health, and we have much to learn about their long-term effects before human crews can venture through the vast voids of space for months at a time."

NASA has worked for years on protecting astronauts from radiation. But Administrator Sean O'Keefe said Wednesday that understanding how the human body responds to long periods in space, and how to mitigate the effects, will become the agency's top research priority, especially at the International Space Station.

"We're reordering ... the very specific emphasis on the research on station to emphasize life science, human physiology, (and) the human effects and consequence of long-duration space flight," O'Keefe said. "This will become the primary, almost singular focus of our research agenda in the time ahead."

The space agency decided about a year ago to focus its radiation-protection efforts through a program based at Marshall.

"We're looking for innovative materials sources to protect the astronauts from damaging radiation" said Ed Semmes, program manager of the Space Radiation Shielding Program, which was created in February 2003. Scientists at other NASA centers, the Department of Energy and universities around the country are involved in the research.

Last fall, NASA commissioned the $34 million Space Radiation Laboratory at the Department of Energy's Brookhaven National Laboratory in Upton, N.Y. The lab is designed to simulate the radiation astronauts encounter in space.

The first material produced by the Space Radiation Shielding Program and tested at the lab was reinforced polyethylene, developed by Marshall scientist Raj Kaul.

Water is a good shield against radiation, and scientists have been using it as a benchmark for the level of protection they are seeking in new materials, Semmes said. Tests show that reinforced polyethylene "behaves very closely to what water does," he said.

Reinforced polyethylene eventually could replace the traditional aluminum skin of spacecraft, Semmes said. "It's about 10 times stronger than aluminum per unit weight," he said.

Because of its strength, reinforced polyethylene also could help in protecting the spacecraft from strikes by small meteoroids, Semmes said. Material that can serve multiple purposes is a key for long-duration missions, Semmes said, because fewer protective layers means less weight.

Spacecraft such as the International Space Station traditionally have been made of aluminum covered with insulation and shields to protect them from meteoroids and other debris.

Other research in the Space Radiation Shielding Program includes work at NASA's Langley Research Center on a radiation shield of foam between two panels of lightweight composite material, Semmes said.

The shielding program is working toward developing a suite of materials by 2008 and a tool for assessing their effectiveness in various circumstances, Semmes said. An informal goal is to deliver a new material every year, he said.

"We would hope to have four to six material design solutions by the time we get to 2008," he said.

The Space Radiation Shielding Program started with an annual budget of $4 million, Semmes said. It will get roughly $6 million this year and level out at around $7 million next year.

A six-month stay on the space station exposes the crew to the equivalent about 600 chest X-rays, more or less depending on how active the sun is during that period, Semmes said.

An astronaut on a mission of several months or more outside Earth's protective magnetic field and ionosphere would face dangerous doses of radiation without protection, Semmes said. "For travel beyond the station, the crew will be exposed to the full intensity of galactic cosmic rays, potentially resulting in the damage to cell tissue and altering genetics, leading to disease such as cancer," he said.

The Space Radiation Shielding Program was started as part of NASA's Space Radiation Initiative. A goal of that initiative is to ensure crews can staff the space station for up to three six-month missions or eventually a 1,000-day mission beyond Earth's orbit without going over radiation exposure limits recommended by the National Council for Radiation Production, according to a NASA press release.

Astronauts who walked on the Moon about 35 years ago didn't face the radiation problem because their missions lasted only a few days, Semmes said. "They just weren't out there long enough to get the exposure," he said.

[ambrose]

Okay...

Here's one thought about the issue of getting astronauts safely back to Earth.

Don't bother...

Let's get some hearty souls are willing to colonize Mars from the get go. Prepare the appropriate equipment, and send them off to arrive in six months. Simultaneously send out numerous other rocket ships containing food, water, vehicle to drive on Mars, equipment to build shelters, etc.

Then we send out supplies as needed.

Is this idea unworkable? If so, why?

[Triple Word Score]

It sounds like a great starting philosophy.

I am writing to my legislators urging them to get the government selling Space Bonds. I want to invest in this. I believe the human race can get fabulously wealthy by expanding (it always has!) and I want to put my money where my mouth is.

And this would let all the weenies who want to stay "safe" on earth opt out. (Like it's safe to keep all your assets in one place!)

[ambrose]

I guess my last point is we're spending too much time obsessing with astronaut safety. The astronauts should know ahead of time that they're volunteering for an extremely risky exploration enterprise for the betterment of all mankind.

Enough with the school teachers and 80 year-old senators!

We need people who will knowingly put their lives on the line to advance our knowledge of the solar system. We will advance by leaps and bounds once we engage in space travel with this basic understanding.

[ambrose]

I love the idea of space bonds. Also see my no. 4.

[Squantos]

I like it !

[Triple Word Score]

Well, it's nice to finish the trip with some bone mass. You could probably get by with less on Mars than you need here. Still, I'm squeamish about that bones-so-weak-your-muscles-pull-them-apart thing.

But I think centrifuge exercise is a good start on that, and that's something every SF reader is well-familiar with. We can do it--it's 14000 BC technology with some good gaskets thrown in. ;-)

The pioneers who crossed the Great Plains often did it barefoot with a handcart at best, and they buried many loved ones on the way. We're their heirs. We owe them a bit more courage than we show.

I think we're afraid of the wrong things!

[LPM1888]

Okay...

Here's one thought about the issue of getting astronauts safely back to Earth.

Don't bother...

Let's get some hearty souls are willing to colonize Mars from the get go. Prepare the appropriate equipment, and send them off to arrive in six months. Simultaneously send out numerous other rocket ships containing food, water, vehicle to drive on Mars, equipment to build shelters, etc.

Then we send out supplies as needed.

Is this idea unworkable? If so, why?

I volunteer to go!!

[Triple Word Score]

I'd go and I'd take my kids and cats with me. That's what pioneers DO!

The dog, though--I'd have to find a home for her.

[BenLurkin]

[Old Student]

Yeah, and what the heck is wrong with school teachers? Or 80-year-old Senators, for that matter? :)

I'm in my late forties, I'll likely be 50 by the time I finish my degree program, and I'd go to Mars in a heartbeat! I started high school in the fall of 1969, and I spent the best part of the summer glued to my B&W TV. By the time we get something put together for a Mars trip, I'm likely to be way over 80. I'd go to the Moon now, if I could get a ticket. Save the young guys for Jupiter and Saturn and beyond!

[ambrose]

I don't see how that's a problem. Russia had cosmonauts on the Mir for nearly two years. Sure they were scrawny and weak when they came back, but they managed.

On Mars, it has 1/3 the Earth's gravity, so it isn't like we'd be floating all over the place. In fact, the lessened gravity would probably be of considerable aid in constructing settlement camps since we'd be able to move the heavy equipment around with much greater ease.

The colonists would simply have to stay on a strict exercise regimen.

[Triple Word Score]

Saturn and beyond--brrrrr!

But it's warmer where Spirit is than it is in New York right now.

http://www.wokr13.tv/news/local/story.aspx?content_id=561A8B2D-697F-4A9B-BCC5-C1B3820B0B00

E=mc2, so we can stay warm ANYWHERE!

[ambrose]

Nothing wrong with teachers or the elderly, but it just mocks our entire space program. NASA can't become some airline to fly around politically approved passengers. It has to be understood this is VERY DANGEROUS and we aren't going to just sit around with our thumbs up our butts for years, not going anywhere, because there might be an accident and an astronaut may die.

[ambrose]

Saturn and beyond--brrrrr! But it's warmer where Spirit is than it is in New York right now.

I wonder what the temperature is on Uranus?

[Triple Word Score]

Yes. No more silly missions-for-show. We need to do it like we mean it, and go to stay.

http://www.heinleinsociety.org/index.html

[Triple Word Score]

The average surface temperature of Uranus is -205 º C.

I don't usually get my butt frosted like that...usually I get it flamed. ;-)

[ambrose]

The place we're going to really want to be at down the line is Titan. It is a treasure trove of natural resources.

Then there's Venus. The Soviets managed to land a few probes that sent back some images, but the probes didn't last long in the 800 degree surface temps. I think it may be quite some time where our technology will be advanced enough to do much exploration there.

[ambrose]

The average surface temperature of Uranus is -205 º C.

My understanding is that Uranus is mostly a bunch of gas, so I don't think we'll be landing any probes there any time soon.

[Triple Word Score]

I just finished rereading IMPERIAL EARTH. You're probably right that Titan could be the key to the solar system; Sir Clarke certainly agreed with you.

(Just found out that Ginny Heinlein died a year ago today. Her ashes were scattered to join her husband's at sea. I don't know if Arthur C. Clarke is still with us or not.)

[Flightdeck]

"Here's one thought about the issue of getting astronauts safely back to Earth.

Don't bother... "

I see a few problems with that scenario. The type of people who currently qualify to fly these multibillion dollar ships are not only smart and in good shape, but they're team players. The combination of these qualities makes one quite an eligible bachelor/bachelorette. Almost all of them have loving families that they wouldn't just give up. The ones who don't have families (vast minority) have very comfortable and pleasure-filled futures ahead of them, assuming they return safely. They all know the risk, but it's either die quickly doing what they love or come back and be a hero; not what you are suggesting.

To give a small example, it was actually fairly tough (by flight director standards) to find astronauts for the MIR missions. Dave Wolf wouldn't have ever flown again if he hadn't volunteered for MIR.

That being said, I'll bet somewhere there are people willing to give up the ultimate gift: "to love and be loved" in order to be such a hero. The question is whether they are the quality to represent our entire nation.

That also being said, no way in hell any president would do it.

[LPM1888]

The pioneers who crossed the Great Plains often did it barefoot with a handcart at best, and they buried many loved ones on the way. We're their heirs. We owe them a bit more courage than we show.

I think we're afraid of the wrong things!

I agree! My Grandparents were pioneers. My Grandmother rode in a covered wagon in one of the Oklahoma Land Rushes. She and her sisters lived in a half dugout. Their mother died when they were young and sometimes they were on their own for months at a time while their father drove their cattle to market. They were willing to take the risks that were required to succeed.

The pioneers lost whole wagon trains and never stopped coming. Now we lose a single Space Shuttle and stop flying for years while we try to make it foolproof. Life will never be foolproof no matter how hard we try. We must keep expanding or mankind will die.

In my Grandparents day if you didn't like your neighbors politics, religion, body odor or if they were too nosy you sold your land and moved west until you found a place more to your liking. Usually that meant homesteading new land.

Now we don't have any new frontiers to move to. That's why we have so much social tension. We have got to develop new frontiers or we will eventually explode into another Civil War. Mankind is not meant to be static, it's just not our nature.

[ambrose]

Here's an actual Soviet image of Venus:

[LPM1888]

We need to form a "wagon train".
My son, cats, and dogs will all go. My dogs are Great Pyranees. They're perfect for the frontier.

[ambrose]

You have some points there. We could also work on sending off a pair of "Adam and Eve" couples...

The problem is that the world is so filled of little ninnies who wouldn't want to put people in a risky situation, even if they were willing and ready for the risk.

[Triple Word Score]

Amen!!!!!!

There is of course no equivalent to the dugout on the moon or Mars. A certain amount of technology is going to be necessary for survival--let alone comfort. But physics has given us the tools. We can do it.

Space bonds! Even if they won't let me go in person, I want to help get our species out of the cradle.

[Old Student]

I think one of the things that you are missing is that the space program was designed so that normal people COULD go into space. They both needed and wanted the publicity, so more people would support the program. Look at the threads on FR, there are many people who don't see the connection between the space program and the advances in computer technology, high-energy physics, oh, too many subjects to mention even a small fraction of them all. What NASA needs to become is some airline to fly around darn-near everyone who wants into space.
Some of the guys going into space recently were WAY older than they would have allowed to fly for NASA just 20 years ago. It was once "late-thirties and grounded" for the Astronauts.
Yes, you're right about the Astronauts being the best of the best, to begin with, but that was just what they needed to get started, people who were used to dealing with untested equipment, sudden danger, and death. That is why they started with test pilots like Chuck Yaeger, and the Seven. The general idea, though, was to make it as normal as commuting to LA, or New York, eventually. Go back and read some of the 40's and 50's SF, you'll see what I mean, if you've never done so before.

[Phil V.]

Let's get some hearty souls are willing to colonize Mars from the get go.

OK . . . Here's the payoff for the feminist-lezbo-futurists . . .

Men are too expensive to ship all the way to Mars. We cultivate some lezbo-techo-chicks willing to build the new society. We ship 'em off with the "cream-of-the-crop" and are able to ship twice as many as if we ship a co-ed crew. . . . Should make for great experiment!

[irv]

NASA has worked for years on protecting astronauts from radiation. But Administrator Sean O'Keefe said Wednesday that understanding how the human body responds to long periods in space, and how to mitigate the effects, will become the agency's top research priority, especially at the International Space Station.>

About f*&!ing time!! This is why leadership counts.

[ambrose]

Hmmm, problem with that idea is the lezbo-feminists are typically luddites who believe that all resources should be directed towards domestic spending.

[LPM1888]

Space bonds! Even if they won't let me go in person, I want to help get our species out of the cradle.

That has been my goal since Alan Shepard first climbed into a Mercury capsule. Maybe that's why I despise politicians so much. They have screwed up the space program beyond belief.

[Triple Word Score]

ambrose:

http://www.prometheus-music.com/eli/virtual.html

Listen to FIRE IN THE SKY.

---

Phil:

It's true that frozen sperm are probably much, much, cheaper to lift than whole men, but when ladies are in labor, they need to be able to snarl at the guilty party. Being on Mars won't change that!

:)

[Phil V.]

. . . plus, who would kill the martian spiders?

[ambrose]

But in ordinary travel, planes crash, and yet the airlines continue to run. With both the Challenger and Columbia, these accidents have effectively grounded the entire space program for a period of years. How can we seriously advance when people believe the program should be accident free? If Apollo 13 didn't make it back, would the space program have been grounded back then?

[RightWingAtheist]

You've been reading too many Pamela Sargent novels :-)

[LPM1888]

There is of course no equivalent to the dugout on the moon or Mars. A certain amount of technology is going to be necessary for survival--let alone comfort. But physics has given us the tools. We can do it.

We will need a high-tech equivalent of a dug-out. Burying the living quarters will provide protection from radiation as well as assisting with stabilizing the environment.

I suggest reading Heinlein's "The Moon is a Harsh Mistress" for an idea of how this might be accomplished.

We can and will do it.

[RightWingAtheist]

[Major_Risktaker]

What stops radiation now?

[Triple Word Score]

Oh, of course--I meant only that it's not going to be a bare-hands operation. This will be done at the leading edge of technology.

[ambrose]

The Ozone layer.

[Phil V.]

What stops radiation now?

Lotsa tinfoil?

[ambrose]

I meant only that it's not going to be a bare-hands operation.

The old Soviet Union (if it hadn't gone bankrupt) could have easily beaten us to Mars, because they would have been willing to do a bare-hands operation. They would have slapped together a rocket ship, tossed in some food, and shipped off the Cosmonauts, whether they liked it or not.

[Old Student]

"The pioneers lost whole wagon trains and never stopped coming. Now we lose a single Space Shuttle and stop flying for years while we try to make it foolproof. Life will never be foolproof no matter how hard we try. We must keep expanding or mankind will die.

In my Grandparents day if you didn't like your neighbors politics, religion, body odor or if they were too nosy you sold your land and moved west until you found a place more to your liking. Usually that meant homesteading new land.

Now we don't have any new frontiers to move to. That's why we have so much social tension. We have got to develop new frontiers or we will eventually explode into another Civil War. Mankind is not meant to be static, it's just not our nature."

Dead on, and your tagline is from one of the guys who practically pioneered the Space Race, himself. He may have turned into a dirty old man in his age, but he had a brain, and wasn't afraid to use it!

Ambrose, if you're not already familiar with Robert A. Heinlein, check out his "juvenile" fiction. I'm particularly fond of Space Cadet, and Have Space Suit, Will Travel, and ... Oh, just read them all! His later fiction, especially The Number of the Beast, and later, was just as powerful, but too loaded with sex; he got into incest and such, which I attribute to brain damage from a blocked carotid artery.

Check out Link to The Heinlein Society or http://www.heinleinsociety.org for more info about him. Many of our astronauts and scientists have mentioned him as a critical factor in sparking their interest in science and space.

[Flightdeck]

Both of you touched on a sore subject I have for the media coverage of the whole "manned spaceflight" issue. On February 2nd, the day after Columbia, if NASA asked the corps for people to go up in Atlantis or Endeavor, it wouldn't have taken more than a minute to fill the seats. Before people put the variable of an astronaut's life into their equation, they should realize that the astronauts both know and accept the risk. That is an important point that is both part of their job description and apparently lost on the uber-shorttermmemory-politicallycorrect media.

[Triple Word Score]

The Earth is blessed with an atmosphere and a magnetosphere that work together to protect the earth's surface from most of the potentially harmful solar radiation. (Hmm, it's like someone planned it that way....)

Consider how quickly you can get a bad sunburn in summer, and be grateful that we don't experience the fullness of Sol's wrath.

Yet we can certainly build a ship that will stop just as much of it.

[LPM1888]

"FIRE IN THE SKY" is excellent!! Thank you!

[ambrose]

Nice (Fire in the Sky).

[Benjo]

With both the Challenger and Columbia, these accidents have effectively grounded the entire space program for a period of years. How can we seriously advance when people believe the program should be accident free?

The problem with the shuttle was that NASA didn't know what to do with it. On the last flight of the Columbia, the astronauts were doing high school science experiments. The shuttles were the space equivalent of the Spruce Goose. They worked, but barely. I'm glad they're (finally) pulling the plug. If there'd never been a shuttle we'd be a lot further along than we are today.

[ambrose]

This is true, but mainly because they never bothered to go to that next step... what next?

Perhaps build a moon base and have the shuttle land there... but I guess the shuttle was never capable of doing something like that?

[Triple Word Score]

No, the shuttle couldn't have done that--we had no way to get it back off the moon.

There's a reusable technology called Phoenix...I'm too tired now to sort out this site which promises to provide information about it...

http://www.hobbyspace.com/Links/RLV/RLVHistory.html

but it's interesting and I'm leaving it in Avant so I can look at it tomorrow.