This still image was taken from a new NASA movie of the sun based on data from NASA's Solar Dynamics Observatory, or SDO, showing the wide range of wavelengths – invisible to the naked eye – that the telescope can view. SDO converts the wavelengths into an image humans can see, and the light is colorized into a rainbow of colors. Yellow light of 5800 Angstroms, for example, generally emanates from material of about 10,000 degrees F (5700 degrees C), which represents the surface of the sun.
Extreme ultraviolet light of 94 Angstroms, which is typically colorized in green in SDO images, comes from atoms that are about 11 million degrees F (6,300,000 degrees C) and is a good wavelength for looking at solar flares, which can reach such high temperatures. By examining pictures of the sun in a variety of wavelengths – as is done not only by SDO, but also by NASA's Interface Region Imaging Spectrograph, NASA's Solar Terrestrial Relations Observatory and the European Space Agency/NASA Solar and Heliospheric Observatory -- scientists can track how particles and heat move through the sun's atmosphere.
Viking sky wolves, Korean fire dogs, and African versions of celestial reconciliation - these are only some of the many ways people around the world, and through the ages, have sought to explain solar eclipses.
People in equatorial Africa will be treated to a rare view of a total solar eclipse this Sunday, November 3. Those living on the eastern North American coast, northern South America, southern Europe, or the Middle East, will get to see a partial solar eclipse. "If you do a worldwide survey of eclipse lore, the theme that constantly appears, with few exceptions, is it's always a disruption of the established order," said E. C. Krupp, director of the Griffith Observatory in Los Angeles, California. That's true of both solar and lunar eclipses. "People depend on the sun's movement," Krupp said. "[It's] regular, dependable, you can't tamper with it. And then, all of a sudden, Shakespearean tragedy arrives and time is out of joint. The sun and moon do something that they shouldn't be doing." What that disruption means depends on the culture, and not everyone views an eclipse as a bad thing, said Jarita Holbrook, a cultural astronomer at the University of the Western Cape in Bellville, South Africa. Some see it as a time of terror, while others look at a solar eclipse as part of the natural order that deserves respect, or as a time of reflection and reconciliation.
Oil, gas, and chemical dispersants contaminated thousands of square miles of marine and coastal habitat. Many animals were killed or sickened outright, but on the one-year anniversary of the Gulf oil spill, scientists still don't know the extent of the spill's effects on most species. Bottlenose dolphins have been dying in unusually high numbers in northern Gulf waters since February 2010, two months before the oil spill began, and the trend continues today. Since January, 68 premature, stillborn, or newborn calves have washed ashore.
The Gulf oil spill is certainly on the list of suspects in the recent dolphin deaths, but it's too early to say for sure, Blair Mase, coordinator of the Southeast Marine Mammal Stranding Network of the National Atmospheric and Oceanic Administration, told National Geographic News in March. Only a handful of obviously oiled dolphins have been recovered. But a recent study from the University of British Columbia estimated that the actual number of dolphins and whales killed by the spill could be 50 times higher than official tallies suggest, putting the death toll in the thousands.
How far away is spiral galaxy NGC 4921? Although presently estimated to be about 310 million light years distant, a more precise determination could be coupled with its known recession speed to help humanity better calibrate the expansion rate of the entire visible universe. Toward this goal, several images were taken by the Hubble Space Telescope in order to help identify key stellar distance markers known as Cepheid variable stars. Since NGC 4921 is a member of the Coma Cluster of Galaxies, refining its distance would also allow a better distance determination to one of the largest nearby clusters in the local universe. The magnificent spiral NGC 4921 has been informally dubbed anemic because of its low rate of star formation and low surface brightness. Visible in the above image are, from the center, a bright nucleus, a bright central bar, a prominent ring of dark dust, blue clusters of recently formed stars, several smaller companion galaxies, unrelated galaxies in the far distant universe, and unrelated stars in our Milky Way Galaxy.
On Oct. 30, 2007, astronauts aboard the Space Shuttle Discovery set out on a routine mission: installing two solar panels on the truss, or backbone, of the International Space Station (ISS). While the first panel deployed successfully, astronauts noticed a two-foot-wide tear in the second panel. To repair the tear, crewmembers devised a risky plan, sending an astronaut on a spacewalk while tethered to the shuttle’s inspection arm. The mission marked the first time an astronaut had used the robotic arm in such a way — a potentially dangerous undertaking, as a wrong move could have electrocuted the spacewalker. In the end, the mission was a success, due partly to the robotic arm’s operators, who were trained to maneuver the multijointed arm with high precision. Today, all incoming astronauts complete extensive training to learn to operate a similar robotic arm on the space station. But the operation isn’t intuitive, and there’s a steep learning curve for some.
MIT researchers in the Man Vehicle Laboratory (MVL) are looking for ways to streamline this lengthy training process. They administered standard cognitive spatial tests to 50 astronauts, and compared these initial results with the astronauts’ performance in NASA’s 30-hour Generic Robotics Training (GRT) course. The researchers found that the initial spatial tests were able to predict the top performers in the more extensive course. The results, says MVL director Charles Oman, suggest that the initial spatial tests may be used as a screening tool to place low-scorers on an in-depth training track, while accelerating high-scorers through a shortened course. “Astronaut training time is a precious resource, and we want to use it as efficiently as we can,” says Oman, who is a senior research engineer in the Department of Aeronautics and Astronautics. “We want to see if there is an objective way of picking people who may be stars, or identifying people who maybe shouldn’t be doing robotics.” Oman and his colleagues have published their results in the journal Acta Astronautica. The paper’s co-authors are research scientists Andrew Liu and Alan Natapoff, and graduate research assistant Raquel Galvan.
About half of all cancer patients have a mutation in a gene called p53, which allows tumors to survive and continue growing even after chemotherapy severely damages their DNA. A new study from MIT biologists has found that tumor cells with mutated p53 can be made much more vulnerable to chemotherapy by blocking another gene called MK2. In a study of mice, tumors lacking both p53 and MK2 shrank dramatically when treated with the drug cisplatin, while tumors with functional MK2 kept growing after treatment. The findings suggest that giving cancer patients a combination of a DNA-damaging drug and an MK2 inhibitor could be very effective, says Michael Yaffe, the David H. Koch Professor in Science and senior author of a paper describing the research in the Nov. 14 issue of the journal Cell Reports.
Several drugs that inhibit MK2 are now in clinical trials to treat inflammatory diseases such as arthritis and colitis, but the drugs have never been tested as possible cancer treatments. “What our study really says is that these drugs could have an entirely new second life, in combination with chemotherapy,” says Yaffe, who is a member of MIT’s Koch Institute for Integrative Cancer Research. “We’re very much hoping it will go into clinical trials” for cancer. Sandra Morandell, a postdoc at the Koch Institute, is the paper’s lead author.
About 10 percent of the U.S. population suffers from dyslexia, a condition that makes learning to read difficult. Dyslexia is usually diagnosed around second grade, but the results of a new study from MIT could help identify those children before they even begin reading, so they can be given extra help earlier. The study, done with researchers at Boston Children’s Hospital, found a correlation between poor pre-reading skills in kindergartners and the size of a brain structure that connects two language-processing areas. Previous studies have shown that in adults with poor reading skills, this structure, known as the arcuate fasciculus, is smaller and less organized than in adults who read normally.
However, it was unknown if these differences cause reading difficulties or result from lack of reading experience. “We were very interested in looking at children prior to reading instruction and whether you would see these kinds of differences,” says John Gabrieli, the Grover M. Hermann Professor of Health Sciences and Technology, professor of brain and cognitive sciences and a member of MIT’s McGovern Institute for Brain Research. Gabrieli and Nadine Gaab, an assistant professor of pediatrics at Boston Children’s Hospital, are the senior authors of a paper describing the results in the Aug. 14 issue of the Journal of Neuroscience. Lead authors of the paper are MIT postdocs Zeynep Saygin and Elizabeth Norton.
For nearly as long as astronomers have been able to observe asteroids, a question has gone unanswered: Why do the surfaces of most asteroids appear redder than meteorites — the remnants of asteroids that have crashed to Earth?
In 2010, Richard Binzel, a professor of planetary sciences at MIT, identified a likely explanation: Asteroids orbiting in our solar system’s main asteroid belt, situated between Mars and Jupiter, are exposed to cosmic radiation, changing the chemical nature of their surfaces and reddening them over time. By contrast, Binzel found that asteroids that venture out of the main belt and pass close to Earth feel the effects of Earth’s gravity, causing “asteroid quakes” that shift surface grains, exposing fresh grains underneath. When these “refreshed” asteroids get too close to Earth, they break apart and fall to its surface as meteorites.
Since then, scientists have thought that close encounters with Earth play a key role in refreshing asteroids. But now Binzel and colleague Francesca DeMeo have found that Mars can also stir up asteroid surfaces, if in close enough contact. The team calculated the orbits of 60 refreshed asteroids, and found that 10 percent of these never cross Earth’s orbit. Instead, these asteroids only come close to Mars, suggesting that the Red Planet can refresh the surfaces of these asteroids.
“We don’t think Earth is the only major driver anymore, and it opens our minds to the possibility that there are other things happening in the solar system causing these asteroids to be refreshed,” says DeMeo, who did much of the work as a postdoc in MIT’s Department of Earth, Atmospheric and Planetary Sciences.
DeMeo and Binzel, along with former MIT research associate Matthew Lockhart, have published their findings in the journal Icarus.