all atmospheric sciences stories

Negative vibes from space

70652986 — Mon, 26 Mar 2007 06:28:27 -0400

Astronomers have discovered the first negatively charged molecule in space, identifying it from radio signals that were a mystery until now. While about 130 neutral and 14 positively charged molecules are known to exist in interstellar space, this is the first negative molecule, or anion, to be found.

"We've spotted a rare and exotic species, like the white tiger of space," said astronomer Michael McCarthy of the Harvard- Smithsonian Center for Astrophysics.

By learning more about the rich broth of chemicals found in interstellar space, astronomers hope to explain how the young Earth converted these basic ingredients into the essential chemicals for life.

Deep-sea sediments could safely store man-made carbon dioxide

Thu, 12 Jul 2007 15:13:59 -0400

An innovative solution for the man-made carbon dioxide fouling our skies could rest far beneath the surface of the ocean, say scientists at Harvard University. They've found that deep-sea sediments could provide a virtually unlimited and permanent reservoir for this gas that has been a primary driver of global climate change in recent decades, and estimate that seafloor sediments within U.S. territory are vast enough to store the nation's carbon dioxide emissions for thousands of years to come.

Super-Earths may be three times more common than Jupiters

70652986 — Mon, 26 Mar 2007 06:25:36 -0400

Astronomers have discovered a new "super-Earth" orbiting a red dwarf star located about 9,000 light-years away. This newfound world weighs about 13 times the mass of the Earth and is probably a mixture of rock and ice, with a diameter several times that of Earth. It orbits its star at about the distance of the asteroid belt in our solar system, 250 million miles out. Its distant location chills it to -330 degrees Fahrenheit, suggesting that although this world is similar in structure to the Earth, it is too cold for liquid water or life.

Orbiting almost as far out as Jupiter does in our solar system, this "super-Earth" likely never accumulated enough gas to grow to giant proportions. Instead, the disk of material from which it formed dissipated, starving it of the raw materials it needed to thrive.

"This is a solar system that ran out of gas," says Harvard astronomer Scott Gaudi of the Harvard-Smithsonian Center for Astrophysics (CfA), a member of the MicroFUN collaboration that spotted the planet.

The discovery was reported March 13, 2006 in a paper posted online at http://arxiv.org/abs/astro-ph/0603276 and submitted to The Astrophysical Journal Letters for publication.

Researchers observe ozone killer

70652986 — Mon, 26 Mar 2007 05:35:41 -0400

Harvard researchers have implicated a particular molecule in the destruction of Earth's ozone layer. The molecule, made up of two chlorine atoms and two oxygen atoms, is called a chlorine monoxide dimer or chlorine peroxide, Cl-O-O-Cl. It has a crucial role in the process by which chlorine destroys atmospheric ozone. Though a variety of chemicals are implicated in ozone loss in the polar winter stratosphere, chlorine is thought to dominate, with a large contribution from bromine radicals. Scientists have been concerned about the impact of man-made processes on the Earth's ozone layer for decades. The ozone layer, a thin band high in the stratosphere, is responsible for shielding the Earth from harmful ultraviolet rays.

Researchers close in on date of critical rise in Earth's oxygen

70652986 — Mon, 26 Mar 2007 05:35:43 -0400

Findings by Harvard researchers and colleagues narrow the range of possible dates for a critical change in the Earth's atmosphere. Scientists had previously believed oxygen first appeared sometime between 2.45 billion and 2.22 billion years ago, a span of about 230 million years. The new findings narrow that window dramatically - to about 130 million years. "It's a fascinating transition, from a physical, chemical, and biological point of view," said Heinrich D. Holland, Harry C. Dudley Research Professor of Economic Geology, who, with postdoctoral fellow Andrey Bekker and colleagues from other institutions, conducted the research. The increase in oxygen allowed the development of early oxygen-using creatures and sowed the seeds for the eventual development of large land animals, an event scientists believe occurred after a second large increase in oxygen more than a billion years later. Whatever the cause, Bekker, Holland, and their colleagues, writing in the Jan. 7, 2004, issue of Nature, detailed their investigation of a black shale, a sedimentary rock thought to have been deposited 2.32 billion years ago in a shallow marine river delta. Researchers examined rock cores drilled by mining companies exploring South Africa's rich mineral resources.

Raging storms of hot and cold gas

70652986 — Mon, 26 Mar 2007 05:34:49 -0400

New observations with the Space Telescope Imaging Spectrograph (STIS), Hubble's high-precision and ultra-sensitive spectrometer, show that the warm chromosphere of Betelgeuse extends out to more than 50 times its radius in visible light, a size five times larger than the orbit of Neptune. (The chromosphere is an inner layer of a star's atmosphere, between the photosphere and the corona. The Sun's chromosphere is visible as a thin reddish line during a total solar eclipse, and extends outward for only a fraction of a solar radius.) STIS detected the spectral signatures of tenuous hot gas in cold, remote, and dusty places of Betelgeuse's mammoth atmosphere. The observations help to determine the mechanisms that form and sustain warm gaseous envelopes in many other red and yellow stars, including the Sun. The team investigated the atmosphere of Betelgeuse, the brightest star in the constellation Orion, over the past five years with the STIS instrument aboard Hubble. They found that the bubbling action of the chromosphere tosses gas out one side of the star, while it falls inward at the other side, similar to the slow-motion churning of a lava lamp. A team led by Alex Lobel of the Harvard-Smithsonian Center for Astrophysics announced the findings at the American Astronomical Society meeting on Jan. 6, 2004.

Picturing a universe that's out of sight

70652986 — Mon, 26 Mar 2007 05:33:26 -0400

Giovanni Fazio, a senior physicist at the Harvard-Smithsonian Center for Astrophysics, directed the design and construction of a camera that is looking beyond the visible universe to see planets, stars, and galaxies being born. On Aug. 25, 2003, he waited for the ignition of a Delta rocket, with extra boosters strapped to it, to blast his life's ambition into an orbit around the sun. The launch was successful, and since December 2003 the best-ever infrared images of the universe have started coming down from space. "They are so spectacular, they are worth the 20 years of heartbreaks," Fazio says. "I feel like a kid in a toy store. It's a science wonderland." The space telescope has been officially named the Spitzer Space Telescope in honor of Lyman Spitzer Jr., an astronomer who first proposed launching telescopes into space to rise above the veiling effect of moisture and dust in Earth's atmosphere. The telescope is operated by the Jet Propulsion Laboratory, a NASA facility in Pasadena, California.

Speedy solar storm reaches Earth

70652986 — Mon, 26 Mar 2007 05:32:43 -0400

An Oct. 28, 2003 eruption created a monstrous solar flare - the third largest recorded since 1976 - and an associated coronal mass ejection, in which superheated gas, called plasma, streaks away from the sun at millions of miles an hour. When the plasma hits the Earth it can disrupt the planet's magnetic field, triggering a geomagnetic storm. The geomagnetic storm associated with this event began at about 4 a.m. Oct. 29 and reached the highest level for such storms - G5 on a scale that starts at G1 - for about three hours before decreasing, according to John Kohl, a solar astrophysicist at the Harvard-Smithsonian Center for Astrophysics. Kohl is the principal investigator for the Ultraviolet Coronagraph Spectrometer on board NASA's Solar and Heliospheric Observatory spacecraft (SOHO) The event could provide some insights as to the sun's magnetic nature, Kohl said. Immediately after the enormous eruption, scientists saw material not only moving toward the Earth, but also moving away from it, as if the force of the explosion blew the magnetic field back, away from the Earth, pulling some material with it. "I think we're going to learn about magnetic fields during this event," Kohl said.

State-of-the-art solar model tracks eruption

70652986 — Mon, 26 Mar 2007 05:31:08 -0400

The Sun may appear to be a bright, steadily shining orb, but it is actually a seething cauldron of hot gases prone to violent eruptions. The most dramatic eruptions are coronal mass ejections (CMEs), in which giant, bubble-shaped balloons of plasma and magnetic field lines blast outward at speeds of up to 1,500 miles per second. CMEs can eject up to 200 billion pounds of matter into interplanetary space. These bursts of plasma can wreak havoc if they impact the Earth. CMEs have the potential to disable satellites, disrupt pager and cell phone networks, and knock out electrical power grids. They also pose a danger to astronauts, particularly future travelers to Mars. Solar physicists Jun Lin (Harvard-Smithsonian Center for Astrophysics) and Terry G. Forbes (University of New Hampshire) have developed a state-of-the-art computer model for the massive solar eruptions. "An astronaut on Mars, unprotected by a strong magnetic field and thick atmosphere like we have on Earth, could be exposed to a lethal dose of radiation and ionized particles. All of these reasons show why it is so important that we understand, and eventually be able to predict, CMEs," said Lin.

Professor honored for ongoing environmental research

70652986 — Mon, 26 Mar 2007 05:29:41 -0400

Harvard Professor Jack Spengler and MIT professor Mario Molina shared the $250,000 Heinz award, which recognized the independent bodies of work by Spengler and Molina, although coincidentally the researchers are collaborating on air quality studies in Mexico City. Spengler, Akira Yamaguchi Professor of Environmental Health and Human Habitation in the Department of Environmental Health at the Harvard School of Public Health, was recognized for his research as well as his advocacy efforts. "Dr. Spengler is a true scientific explorer, having charted, virtually by himself, an undiscovered environmental scourge -- indoor air pollution," said Teresa Heinz, chairman of the Heinz Family Foundation. "He has succeeded in focusing the nation's attention on a new insidious, invisible threat, one that had been silently and adversely affecting the nation's health. The technology that scientists rely on today for critical air pollution measurements would not have been possible without Dr. Spengler's pioneering work." Spengler is currently helping to lead the Healthy Public Housing Initiative, an endeavor to respond to high levels of asthma in low-income communities in Boston. He was co-editor of the Indoor Air Quality Handbook. Earlier in his career, he was a researcher with the groundbreaking Six Cities Studies, which explored the environmental risks associated with sulfur dioxide and particle emissions from coal-burning power plants. The studies found a lethal relationship between particulate matter and cardiovascular mortality.

Putting bacteria to work

70652986 — Mon, 26 Mar 2007 05:24:01 -0400

A nautical group of bacteria known as Prochlorococcus removes carbon dioxide from air and fixes it into the carbon content of their own tiny bodies. The more carbon dioxide they take from the air, the less is available to capture the heat that is causing the warm-up of our planet. That adds up to a lot of carbon. "Prochlorococcus is a major ocean sink for carbon," says George Church, professor of genetics at Harvard Medical School and a faculty member of the Harvard-M.I.T. Division of Health Sciences and Technology. "It is responsible for 40 percent of the photosynthesis (carbon dioxide removal) on Earth." A quart of ocean water often contains 100 million Prochlorococcus cells. Its population in the global ocean could be as high as 10 trillion trillion.

Weather watchers forecast better forecasts

70652986 — Mon, 26 Mar 2007 05:23:37 -0400

Brian Farrell, the Robert P. Burden Professor of Meteorology, is spearheading a project that is part of a five-year initiative funded by the National Science Foundation and the Office of Naval Research to spark progress in the general area of predictability of the atmosphere and oceans. "Right now we have a fairly good forecast out to 48 hours," Farrell says, "maybe two or three days. After that, you never know." The reason for this, he adds, is that starting out with a certain amount of error is inevitable. Both the observational data and the mathematical model used to parse it are imperfect; the necessity of using them together only compounds the problem.

South Pole telescope maps heart of Milky Way

70652986 — Mon, 26 Mar 2007 05:21:54 -0400

Research results obtained by a team of astronomers at the Harvard-Smithsonian Center for Astrophysics (CfA) led by Chris Martin and Antony Stark suggest that we are headed for some celestial fireworks. Sometime in the next 300 million years, the galactic center will experience a dramatic burst of star formation and will shine with the light of thousands of newborn suns. The effects of these starbursts will be dramatic. "Many of the stars that form will be very massive and short-lived," says Stark. "They'll quickly use up their fuel and explode as supernovae. Right now, we see one supernova in our galaxy about every 100 years. When the starburst happens, we'll see one supernova every year."

Scientists predict calmer weather ahead

70652986 — Mon, 26 Mar 2007 05:20:03 -0400

When the Sun is more active, it has bad effects on our planet. For instance, energy from solar eruptions changes the orbits of satellites, causing them to spiral back to the Earth. Solar eruptions perturb the Earth's magnetic field, causing communications disruptions, especially to cell phone and other wireless devices. Magnetic storms also cause current surges in power lines that destroy equipment and knock out power over large areas. Now, a new instrument called the Ultraviolet Coronagraph Spectrometer, or UVCS, is allowing first-of-a-kind observations by astronomers. The observations are providing the best descriptions yet of the workings of the Sun from its core to its surface. Recent observations have convinced astronomers that calmer weather is ahead in space. Such observations also are leading the way to better long-term predictions of how and when the Sun's gusty particle emissions will affect spacecraft and life on Earth. Improved predictions are expected after next-generation instruments come on line later in the decade. "We need these better predictions as we become more dependent upon satellites and reliable long-distance communications," says Mari Paz Miralles of the Harvard-Smithsonian Center for Astrophysics.

Oceans key to global warming

70652986 — Mon, 26 Mar 2007 05:19:55 -0400

One of the largest unknowns about global warming is, How much of an overload of man-made carbon dioxide can the Earth take?