Space

NASA study finds increasing solar trend that can change climate

Since the late 1970s, the amount of solar radiation the sun emits, during times of quiet sunspot activity, has increased by nearly .05 percent per decade, according to a new NASA funded study. “This trend is important because, if sustained over many decades, it could cause significant climate change,” said Richard Willson, a researcher affiliated with NASA’s Goddard Institute for Space Studies and Columbia University’s Earth Institute, New York. He is the lead author of the study recently published in Geophysical Research Letters. “Historical records of solar activity indicate that solar radiation has been increasing since the late 19th century. If a trend, comparable to the one found in this study, persisted throughout the 20th century, it would have provided a significant component of the global warming the Intergovernmental Panel on Climate Change reports to have occurred over the past 100 years,” he said.

Experiment may help size up neutrinos

A new experiement in Israel may help rectify the disparity between how many neutrinos scientists think should be produced by the Sun and how many have been detected at research stations around the world.

Worried About Asteroid-Ocean Impacts? Don't Sweat the Small Stuff

The idea that even small asteroids can create hazardous tsunamis may at last be pretty well washed up. Small asteroids do not make great ocean waves that will devastate coastal areas for miles inland, according to both a recently released 1968 U.S. Naval Research report on explosion-generated tsunamis and terrestrial evidence. University of Arizona planetary scientist H. Jay Melosh is talking about it today at the 34th annual Lunar and Planetary Science Conference in League City, Texas. His talk, “Impact-Generated Tsunamis: an Over-Rated Hazard,” is part of the session, “Poking Holes: Terrestrial Impacts.”

Pulsar Bursts Coming From Beachball-Sized Structures

In a major breakthrough for understanding what one of them calls “the most exotic environment in the Universe,” a team of astronomers has discovered that powerful radio bursts in pulsars are generated by structures as small as a beach ball. “These are by far the smallest objects ever detected outside our solar system,” said Tim Hankins, leader of the research team, which studied the pulsar at the center of the Crab Nebula, more than 6,000 light-years from Earth. “The small size of these regions is inconsistent with all but one proposed theory for how the radio emission is generated,” he added.

European astronomers observe first evaporating planet

Using the Hubble Space Telescope, astronomers have, for the first time, observed the atmosphere of an extrasolar planet evaporating into space. Much of this planet may eventually disappear, leaving only a dense core. It is a type of extrasolar planet known as a ‘hot Jupiter’. These giant gaseous planets orbit their stars very closely, drawn to them like moths to a flame. The scorched planet called HD 209458b orbits ‘only’ 7 million kilometres from its yellow Sun-like star. By comparison, Jupiter, the closest gas giant in our Solar System, orbits 780 million kilometres from our Sun. NASA/ESA Hubble Space telescope observations reveal a hot and puffed-up evaporating hydrogen atmosphere surrounding the planet. This huge envelope of hydrogen resembles a comet with a tail trailing behind the planet. Earth also has an extended atmosphere of escaping hydrogen gas, but the loss rate is much lower.

Clouds mitigate effects of warming on Arctic

Cloudy weather may dampen the human spirit, but it also may dampen the effects of global warming on the Arctic, according to new study published in the March 14 issue of the journal Science. Data from dozens of meteorological stations show that the surface temperature across Arctic land and water keeps getting warmer. However, researchers at the University of Wisconsin-Madison now show that Arctic clouds and the climate conditions with which the clouds interact produce a cooling effect, possibly offsetting to some degree the effects of global warming in this region.

Virtual observatory prototype produces surprise discovery

A new approach to finding undiscovered objects buried in immense astronomical databases has produced an early and unexpected payoff: a new instance of a hard-to-find type of star known as a brown dwarf. Scientists working to create the National Virtual Observatory (NVO), an online portal for astronomical research unifying dozens of large astronomical databases, confirmed discovery of the new brown dwarf recently. The star emerged from a computerized search of information on millions of astronomical objects in two separate astronomical databases. Thanks to an NVO prototype, that search, formerly an endeavor requiring weeks or months of human attention, took approximately two minutes.

NASA Maps Reveal Dinosaur Crater

From Canada to Central America, the many grandeurs of North America’s diverse topography star in a just-released high-resolution map from NASA’s Shuttle Radar Topography Mission. But a relatively obscure feature, all but hidden in the flat limestone plateau of Mexico’s Yucatan Peninsula, is what emerges as the initial showstopper from the mission’s first released continental data set. The existence of the impact crater known as Chicxulub (Chik-sah-loob) was first proposed in 1980. In the 1990s, satellite data and ground studies allowed it to gain prominence among many scientists as the long sought-after “smoking gun” responsible for the demise of the dinosaurs and more than 70 percent of Earth’s living species 65 million years ago. Now, the Shuttle Radar Topography Mission has provided the most telling visible evidence to date of a 180-kilometer (112-mile) wide, 900-meter (3,000-foot) deep impact crater, the result of a collision with a giant comet or asteroid on one of Earth’s all-time worst days.

NASA-funded research looking at El Ni?o events to forecast western US snowfall

A NASA-funded study uses a computer model to understand an observed link between winter and spring snowfall in the Western U.S. and El Ni?o Southern Oscillation. Almost 75 to 85 percent of water resources in the Western U.S come from snow that accumulates in the winter and early spring and melts as runoff in spring and summer. Understanding this connection and using it to predict future snowfall rates would greatly help both citizens and policy makers.

Nasa finds 'cocoon' inside the Black Widow's web

NASA’s Chandra X-ray Observatory image of the mysterious “Black Widow” pulsar reveals the first direct evidence of an elongated cocoon of high-energy particles. (A pulsar is a rotating neutron star producing powerful beams of radiation that sweep like a searchlight.) This discovery shows this billion-year-old rejuvenated pulsar is an extremely efficient generator of a high-speed flow of matter and antimatter particles.

NASA spots monster gas cloud around Jupiter moon

Using a sensitive new imaging instrument on NASA’s Cassini spacecraft, researchers have discovered a large and surprisingly dense gas cloud sharing an orbit with Jupiter’s icy moon Europa. Stretching millions of miles around Jupiter, the donut-shaped cloud, known as a “torus,” is believed to result from the uncommonly severe bombardment of ion radiation that Jupiter sends toward Europa. That radiation damages Europa’s surface, kicking up and pulling apart water-ice molecules and dispersing them along Europa’s orbit into a neutral-gas torus with a mass of about 60,000 tons.

OK, our next caller is… from Mars!

It is midnight on 1 January 2004 and you want to send a greeting on your mobile phone to a friend. Sorry, the line is too busy, try again later. If you think you are alone with this problem, you are wrong. Space agencies have had to work out ingenious solutions to prevent similar ‘engaged, call later’ tones from happening on Mars. For the first time, there will be seven spacecraft on the Red Planet at the same time. Will they all be able to ‘phone home’?

Bon voyage: Pioneer 10 spacecraft bids adieu

After more than 30 years, it appears the venerable Pioneer 10 spacecraft has sent its last signal to Earth. Pioneer’s last, very weak signal was received on Jan. 22, 2003. NASA engineers report Pioneer 10’s radioisotope power source has decayed, and it may not have enough power to send additional transmissions to Earth. NASA’s Deep Space Network (DSN) did not detect a signal during the last contact attempt Feb. 7, 2003. The previous three contacts, including the Jan. 22 signal, were very faint with no telemetry received. The last time a Pioneer 10 contact returned telemetry data was April 27, 2002. NASA has no additional contact attempts planned for Pioneer 10.