Stories tagged nasa

I breathed a big sigh of relief when I heard that the space shuttle Discovery landed safely this morning at about 9:14 EDT. Thank goodness.

May
01
2006


Comet breaks up near Earth: Credit for Hubble Images: NASA, ESA, H. Weaver (JHU/APL), M. Mutchler and Z. Levay (STScI)

A comet is experiencing a spectacular break up as it swings around the sun. It will be at its closest on May 12th. Don't worry! It will be 30 times further away than the moon. Comets are mostly dirty ice. As the sun heats these slush balls they often break up. Even more spectacular is when an inner pocket of vapor bursts through the surface and acts like a rocket propelling that fragment in the opposite direction.

Is this a newly discovered comet?

German astronomers Arnold Schwassmann and Arno Arthur Wachmann discovered this comet during a photographic search for asteroids in 1930, when the comet passed within 5.8 million miles of the Earth (only 24 times the Earth-Moon distance). The comet orbits the Sun every 5.4 years, but it was not seen again until 1979. Astronomers observed its initial breakup into four pieces that year. The comet was missed again in 1985 but has been observed every return since then.

Hubble still taking pictures after 16 years.

NASA and the European Space agency have released new images from the Hubble Space Telescope showing the dramatic breakup of comet Schwassmann-Wachmann 3. The comet's nucleus has shattered into more than 33 pieces, and is likely to continue to disintegrate. They have even put several pictures together to create a movie of the breakup. Choose one from this page
Source:Hubblesite.org

Dec
27
2005

Imagine that you are on a glacier and all around you thousands of black worms rise up out of the ice. It sounds like a scene from a science fiction movie, but it isn't. The worms are ice worms, and they're real.

Ice worms are extremophiles, animals that thrive in conditions that most creatures would not be able to survive, such as volcanos, glaciers and deep in the ocean. Ice worms live in glacial ice. They average around 1 cm long and 1 mm wide, and eat snow algae. Ice worms are the opposite of worms like earthworms, in that instead of becoming less active as temperature decreases, ice worms become more active with cooler temperatures. And there are a lot of them. One glacier can have an ice worm density of 2600 worms per square meter.

The ideal temperature for an ice worm is zero degrees Celsius, or 32 degrees Fahrenheit. This ability of ice worms to thrive in such extreme temperatures is the focus of a three year $214,206 NASA grant. Researchers hope ice worms can help unlock the secrets of how life might survive on distant ice worlds such as Europa.

Ice worms actually disintegrate through the process of autolysis when they are exposed to temperatures greater than 5 degrees Celsius. (Autolysis in cell biology refers to the destruction of a cell by its own digestive enzymes.) With the glaciers that are the only habitat for these organisms slowly melting due to global warming, ice worms are losing their habitat. If you consider that there are over 7 billion worms in one glacier, their impact on ecologies that are influenced by the glaciers must be significant, both in terms of biomass and in terms of nutrient processing. There is a lot more to learn about these organisms, and the role they play in the ecosystem.

For a time ice worms were believed to be mythical creatures — there is even an amusing poem that features the ice worm. I never knew these things existed — pretty amazing worm, I think.

Jul
19
2005


Microscopic image of turkey muscle cells grow in culture.: Image Credit: University of Maryland

A recent article in the journal Tissue Engineering proposes two ways for laboratories to grow artificial meat. One method would be to grow cells from common livestock animals like cows or chickens in large flat sheets. The thin sheets would then be stacked to resemble meat. The other proposed method would be to grow muscle cells on small beads that stretch with small changes in temperature. The tissue produced could be used to make processed meat such as hamburgers or chicken nuggets.

The research is being done at the University of Maryland and is based on experiments NASA has conducted to grow artificial meat for space missions.

But why produce artificial meat commercially?

One reason would be to make meat healthier for the consumer. Meat contains a lot of omega-6 fatty acid, which is good, but not in large amounts. The omega-6 fatty acids could be replaced with omega-3 fatty acids which are more beneficial.

Another reason is that raising livestock has a huge environmental impact. Livestock require millions of gallons of water, large amounts of land, and produce huge amounts of waste. The use of artificial meat would help to protect the environment by potentially reducing the number of livestock needed to meet the demands for meat.

Further, the production and consumption of meat has many additional potential issues including meat-borne pathogens and contaminants, antibiotic-resistant bacteria due to the routine use of antibiotics in livestock, and inhumane treatment of farm animals.

The author of the paper, University of Maryland doctoral student Jason Matheny, sees so many advantages in the production of artificial meat that he joined several other scientists in starting a nonprofit, New Harvest, to advance the idea.

Would you eat artificial meat?

May
20
2005


Grainy Mars Orbiter pictureCourtesy NASA

For the first time ever, a spacecraft has taken a picture of another spacecraft orbiting around another planet. The Mars Global Surveyor, which has been floating around Mars since 1997, was able to take this grainy picture of its sister probe, Odyssey. Odyssey arrived at Mars in 2001. It's exciting to be able to see evidence of our successful missions to another planet beamed back from millions of miles away.

In the future these probes may be able to take pictures of fellow spacecraft to help us fix problems and guide discovery. Imagine if a lander got lost on the Martian surface: orbiting probes might be able to tell us back here on Earth what happened, and where things went wrong. This sort of interaction between probes will be essential for our further exploration of the universe, especially to places where humans might not be able to travel.

Apr
25
2005

Scientists in England have figured out a way to read ancient Greek and Roman scrolls that had previously been illegible. These scrolls were found about 100 years ago in a garbage dump. Most of the hundreds of scrolls were dirty, moldy stained or burnt, and couldn't be read.

Dead Sea Scroll FragmentPreviously invisible lettering of the Dead Sea Scrolls
Courtesy NASA/JPL-Caltech

In the early '90s, scientists working on the Dead Sea scrolls teamed up with NASA and developed a way to photograph the ancient paper using invisible wavelengths of light. (Light comes in a wide variety of wavelengths. Our eyes only respond to some of them. But scientists can build cameras that respond to wavelengths too long or too short for our eyes to see.)

Already, scientists have discovered lost works by Sophocles, Euripides, and other famous writers of the ancient world. Some feel these discoveries could completely rewrite our understanding of ancient Greece and Rome — and the beginnings of Western civilization.

Feb
21
2005

News reports last week indicated that scientists had found methane on Mars—a chemical that usually indicates life. However,
NASA says it ain't so.

"News reports on February 16, 2005, that NASA scientists from Ames Research Center, Moffett Field, Calif., have found strong evidence that life may exist on Mars are incorrect.

"NASA does not have any observational data from any current Mars missions that supports this claim. The work by the scientists mentioned in the reports cannot be used to directly infer anything about life on Mars, but may help formulate the strategy for how to search for martian life. Their research concerns extreme environments on Earth as analogs of possible environments on Mars. No research paper has been submitted by them to any scientific journal asserting martian life."

Feb
08
2005

Even though the Hubble Space Telescope has been one of the most popular NASA missions ever, NASA administrators and President Bush have made the hard decision to let the telescope fail.

What's special about the Hubble Telescope? Clouds and light pollution—the brightening of the night sky by human activities—affect what we can see from Earth. A telescope in outer space doesn't have those limitations.