Curiosity shoplifted

With shifts in federal scientific funding from open-ended research to technology development, one Washington Post columnist writes that we are in danger of losing our sense of curiosity. Are we too focused on short-term progress and profits? Are we no longer interested in exploring for the sake of exploring? Link.

Invasive species

According to May’s issue of Discover, the species invasion has already begun: dandelions, purple loosestrife, Cuban tree frogs, etc. The success of an invading species depends on its ability to find and exploit a niche in a new ecosystem. When an alien species enters a new ecosystem, it can cause a stir by eating native species, spreading disease, competing better against local decease, or changing the environment in such a way that favors itself. But, most invasive species just take their place quietly. Purple loosestrife, for example, is taking over wetlands and backyards in the northeast. Although local ecologists are sounding the alarm, a zoological study concluded that there is little or no evidence that its invasion has any serious ecological consequences. We traditionally see invasive species as deceases that ruin natural ecosystems. But invasion biologists don’t see it that way. Invasions don’t cause ecosystems to collapse; in fact, invasive species can make an ecosystem healthier by increasing the local biodiversity. Although a new species may not be as useful or attractive to humans, the new, more competitive species will make the ecosystem stronger. (You might not be able to read the story without a password.) Link.

US Senate supports the stem cell bill

The human embryonic stem cell research bill has a lot of support in the US Senate, despite its opposition by President Bush. Senator Arlen Specter, the Pennsylvania Republican and chief sponsor of a bill, said Wednesday that he had enough votes in the Senate to override a presidential veto of the measure. The measure approves the use of federal funding for embryonic stem cell research, and goes against the President's 2001 executive order that banned funding of the controversial research. Link.

What is human embryonic stem-cell research? Stem cells are the first few cells that form after a fertilized egg divides. They are medically the most useful cells because as they grow and subdivide, they can turn into any type of cells, such as spinal cord cells or heart muscle cells. So, any kind of damaged human tissue can be replaced by tissue regenerated from stem cells, giving hope to the many who suffer from spinal cord injury, diabetes, Alzheimer’s, or many other conditions. Link.

Why is embryonic human stem-cell research so controversial? The controversy comes into play when scientists make a new cell line. When a new human stem cell line is made, a human egg is fertilized in order to generate the stem cells. The moral issue is whether or not harvesting stem cells from the fertilized human egg is morally the same as taking a life, because under the right conditions, the fertilized egg could grow into a whole human being. The President's supports federal funding of human embryonic stem-cell research only if no new stem cell lines are made. But here's the problem: in-vitro fertilization, a common procedure for couples with problems conceiving a child, produces thousands of unused fertilized eggs every year. The bill currently in Congress doesn't suggest that we should fertilize human eggs just to do medical research on them, it supports funding for research done on the embryos discarded from in-vitro fertilization.

How long could you survive in the vacuum of space?

As the school year comes to an end for seniors, I traditionally show the film 2001: A Space Odyssey. In the film, astronaut Dave Bowman finds himself stuck in a small space pod, locked out of the main spacecraft, without the helmet to his spacesuit. Forced to enter through the emergency air lock, Dave is briefly subjected to the vacuum of space. Is it possible for him to survive? The answer, according to science fiction writer Geoffrey Landis, is YES. Landis, who referenced several sources, explains that a human can remain mentally conscious in the vacuum of space for about 10 seconds, and survive that environment for about 90 seconds. As soon as the astronaut hits the vacuum, air will be knocked out of the lungs through the nose and mouth. Space is a very cold and very hot place; without an atmosphere to even things out, the difference between sunlight and shade is 400 degrees F. The mouth and tongue may freeze, it will only take a short time for skin not exposed to the sun to get lightly frostbitten, and skin exposed to the sun will be badly sunburned. But that's about the worst of it inside of 90 seconds of exposure. Unless the astronaut tries to hold their breath...this will cause the lungs to rupture. So, as a safety tip, if you’re going for a space walk without a helmet, keep your mouth open. Eventually, like deep-sea divers coming up to the surface too quickly, gas bubbles will form in the astronaut's blood and soft tissues -- a condition called "the bends". Hypothermia, or a harmful drop in core body temperature, will set in, but is not a short-term concern. Link.

Turn that moon dust into oxygen and win

Moon dust engineers are in high demand these days. NASA has a quarter of a million dollar prize up for grabs for the first team to make oxygen from moon dust. The machine must meet NASA's weight and power limits, and must be able to extract at least five kilograms of oxygen from a sample of volcanic ash in eight hours. Volcanic ash is very similar to moon dust, and obviously a lot easier to get one's hands on. For the machine to work, it will need to release oxygen atoms from the silica and other minerals that form the majority of volcanic and lunar rock. One way to separate oxygen from the rock is to use an electric current to separate negatively charged oxygen from the positive ions to which it is bound. Link.

Moon dust in your hair

NASA is funding a four-year study at the Colorado School of Mines on extra-terrestrial dust control. The surface of the moon is covered with a fine, talcum-like powder, the kind of stuff that kicks up really easily. Since the gravity on the moon is only one-sixth of Earth, humans and machines that disturb the moon ground will make lots and lots of dust. Stuck to spacesuits and boots, the dust is easily tracked into a lunar lander, where it gets quite annoying, gumming up equipment and covering instrument displays. The particles of moon dust can be harmful to lungs if inhaled over a long period of time. This is a major concern for long-term moon expeditions of the future. The dust problem will also be a major concern for astronauts sent to Mars, perhaps much worse. Mars dust contains the highly reactive compound iron-oxide, which, in essence, burns skin and can severly irritate lung tissue. The dust will be driven by the harsh wind storms that occur on Mars' surface. Link.

South Korea takes the lead in stem cells

Last year, a team of scientist from South Korea made the first stem-cell line from cloned human cells. A stem-cell line is a source of cells from a donor that scientists can go back to indefinitely to gather stem cells for study. Recently, the South Korean scienctists have taken the work a big step further by making stem-cell lines from several patients with different diseases, such as autism, diabetes and Parkinson’s. By studying these lines, they may be able to watch how diseases unfold, and develop cures. The cell lines will be used to test new drugs, without risks to human or animal subjects. Despite what you may have heard, science is a long way away from being able to grow complete replacements for deceased organs.

To make a cell line, scientists take a sample of skin cells from a donor. They then suck out the nucleus of each skin cell, and implant it in a human egg whose own nucleus has been removed. The eggs grow into a round structure of cells, a structure that forms early in human development. Scientists remove the stem cells from this structure and transfer them to a place where they can grow until researchers are ready to experiment on them.

Meanwhile, back in the US, stem cell research is being slowed by bioethical controversy and a presidental ban on government funding for stemcell research. “There is a good chance that the US will be left behind as the situation on stem cell research there becomes more fragmented and incoherent,” says UK scientist Stephen Minger, of King’s College London. Link.

Antarctica ice on the move

Nature.com reported on April 21 that 87 percent of 244 Antarctic glaciers have been retreating in the past 40 years. The likely cause is that the Antarctic Ocean temperature has risen 2 degrees C in the last 50 years. Link. A May 19 Nature.com article reported that scientists have also observed that the overall thickness of the ice layer in East Antarctica is increasing. They explain that the warmer oceans evaporate more moisture into the Antarctic air, which results in greater snowfall on the continent. The thickening of the ice layer has previously been predicted by global warming models. In time, the rate of glacier retreat will make up for the increase in Antarctic snow fall, and sea levels will slowly rise. Link.

NASA plans to fix the Hubble, but postpones other stuff

NASA is proceeding with plans to send a shuttle mission to repair and upgrade the ailing Hubble Telescope, reversing their previous decision to simply let the telescope die. The bad news is that funding the Hubble mission would mean the indefinite postponement of two future missions to search for extrasolar planets - the Space Interferometry Mission, which had been scheduled for 2011, and the Terrestrial Planet Finder, which was set to launch in 2014. It is also possible that the next rover mission to Mars, the Mars Science Laboratory, will be pushed back to from 2009 to 2011. Link.

New species of rodent a tasty treat

“It was for sale on a table next to some vegetables,” says conservation biologist Robert Timmins, “And I knew immediately it was something I had never seen before.” The rock rat, as it's called, is a completely new species of rodent. The creature looks like a cross between a large dark rat and a squirrel, but is actually more closely related to guinea pigs and chinchillas. People in the Khammouan region of Laos prepare it by roasting it on a skewer. Link.

Let's send a rover to Venus

Could we have as much success landing a rover to explore Venus as we did with our other closest neighbor, Mars? Venus is a much tougher environment than Mars, but NASA still has an interest in exploring there. The atmospheric pressure on the surface of Venus is about 90 times greater than Earth's. A Venicean day lasts 117 Earth days, daytime temperatures reach 450 degrees C, and the dense atmosphere is acidic. A ground-traveling Venus rover will have to be extremely acid-proof, heat-proof, leak-proof, and pretty dumb, because at such high temperatures, it is not currently possible to operate electronics on a ground-based Venus rover. Because of this, NASA is designing an aircraft to orbit Venus and hold the rover's electronics to process data and communication. The orbiting aircraft would take advantage of the dense atmosphere, using wings and a propeller. The orbiter would float up in the cooler altitudes and collect the intense solar energy, which should keep it powered indefinitely. Link.

One of Saturn's moons is not like the others

Astronomers have confirmed what they have suspected about Saturn's moon Phoebe: the potato-like moon didn't come from Saturn. They new that the direction and tilt of Phoebe's orbit is different from the other moons of Saturn, and data from the Cassini-Huygens probe show more differences. For instance, Pheobe has much less ice and much more rock than the other moons. It is most likely that Pheobe came to Saturn from the Kuiper belt, a ring od icy rocks past Neptune. Cassini data also show that some of the minerals and organic molecules on Phoebe's surface are typical of objects in the Kuiper belt. Link.