Science Scanner: Asteroid Narrowly Misses Earth

A lot of folks on Earth breathed a collective sigh of relief when an asteroid, the size of an aircraft carrier, sailed past us without causing any harm.

Yesterday, Nov. 8, 2011 at approximately 2328 UTC, the asteroid 2005 YU55 came within 324,604.685 kilometers of Earth, making it the biggest asteroid in 35 years to have such a close encounter with Earth. The  space rock came closer to us than our own moon.

Scientists tracking the asteroid’s trajectory believed all along that it didn’t pose any real danger to us.  Also, the gravitational influence of the asteroid shouldn’t have any detectable impact on Earth, including its tides and tectonic plates.

The last time such a huge space rock came that close to Earth was in 1976, and astronomers didn’t even know about it until afterward. The next known approach of an asteroid this large will be in 2028.

Meanwhile, scientists working with the 70-meter-wide Deep Space Network antenna at Goldstone, California, have generated a short movie clip of asteroid 2005 YU55.

The images were produced from data gathered on Nov. 7, 2011, between 1624 and 1835 UTC. NASA says that they are the highest-resolution images ever generated by radar of a near-Earth object.

You can watch this brief movie, produced by NASA’s Jet Propulsion Laboratory, by clicking on the graphic above.

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Russian space probe stalls in space

The Zenit-2SB rocket with Phobos-Grunt craft blasts off from the Cosmodrome in Baikonur, Kazakhstan, early Wednesday, Nov. 9, 2011. (AP Photo/Oleg Urusov, Pool)

In other space news,  the Russian space program suffered another setback Tuesday when its first planned interplanetary mission in almost two decades failed to take its proper course toward Mars. It is now stuck orbiting Earth.

Russian space agency chief Vladimir Popovkin said an engine failed to fire on the 5-billion-ruble ($163 million) Phobos-Grunt probe after it reached Earth’s orbit.

“The engine did not fire, neither the first nor the second burn occurred. This means that the craft was unable to find its bearings by the stars,” the Interfax news agency quoted Popovkin as saying at Russia’s Baikonur launch facility in Kazakhstan.

This leaves Moscow space officials with a limited amount of time to yank the probe out of its current orbit and back onto its path toward Mars before the spacecraft’s batteries are completely drained.

If  the problem isn’t fixed, not only will the Russian probe’s mission to the Mars moon Phobos be in danger, but also that of China’s first interplanetary spacecraft. The tiny Yinghuo-1 was launched with Phobos-Grunt and is to work with it in orbit, studying the atmosphere of Mars for a year.

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Scientist struggle to understand water

Water… good ole H20, one of the simplest chemical compounds, is providing chemists with an odd twist. When chilled below the freezing point, it can shift into a new type of liquid, according to a report in the Journal of Physical Chemistry B.

Researchers, Pradeep Kumar of New York’s Rockefeller University and H. Eugene Stanley of Boston University, say  water is one weird substance, exhibiting more than 80 unusual properties, some of which scientists are struggling to understand.

For example, they say, water can exist in all three states of matter – solid, liquid and gas – at the same time, and that the forces at its surface enable insects to walk on water, and cause water to rise up from the roots into the leaves of trees and other plants.

In another strange turn, the scientists propose that water can go from being one type of liquid into another in a so-called “liquid-liquid” phase transition. However, they also say it is impossible to test this with today’s laboratory equipment because these things happen so fast.

So the researchers here resorted to computer simulations to check it out.

What they learned was when they chilled liquid water in their simulation, its ability to conduct heat decreased. That’s expected for an ordinary liquid. But, when they lowered the temperature to about 54 degrees below zero Fahrenheit, the liquid water started to conduct heat even better in their simulation.

Their research suggests that, below this temperature, liquid water undergoes sharp but continuous structural changes where the local structure of liquid becomes extremely ordered – very much like ice. These structural changes in liquid water lead to an increase of heat conduction at lower temperatures.

The researchers say this surprising result supports the idea that water has a liquid-liquid phase transition.

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Searching for the fountain of youth

Drosophila melanogaster aka the common fruit-fly (Photo: André Karwath (Own work) via Wikimedia Commons)

Scientists at UCLA might be on the road to discovering the  “fountain of youth.”  Life scientists at the California university say they’ve identified a gene which slows the aging process.

Working with fruit flies, the scientists activated a gene called PGC-1, which increases the activity of mitochondria, the tiny power generators in cells that control cell growth and tell cells when to live and die.

“We took this gene and boosted its activity in different cells and tissues of the fly and asked whether this impacts the aging process,” says UCLA’s David Walker,  senior author of the study. “We discovered that when we boost PGC-1 within the fly’s digestive tract, the fly lives significantly longer.”

Just activating this one gene in the fruit fly’s intestine caused the aging process of the intestine to slow, producing a positive effect on the entire insect itself, according to Walker.

The biologists say that they were able to extend the lives of their fruit-fly specimen by as much as 50 percent.

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