A fleet of orbiting x-ray telescopes has been used by an international team of scientists in the discovery of a "millisecond pulsar" star with a dual identity. The star readily shifts back and forth between two mutually exclusive styles of pulsed emissions, one in x-rays, the other in radio waves. The discovery, the scientists say, reveals a long-sought intermediate phase in the life of these powerful objects.
For astrophysicists, the interplay of hydrogen and the clouds of dust that fill the voids of interstellar space has been an intractable puzzle of stellar evolution. The dust, astronomers believe, is a key phase in the lifecycle of stars, which are formed in dusty nurseries throughout the cosmos. But how the dust interacts with hydrogen and is oriented by the magnetic fields in deep space has proved a theoretical challenge. Until now.
Kids grumble about homework. But their complaints will hold no water with a group of theoretical physicists who’ve spent almost 50 years solving one homework problem: a calculation of one type of subatomic particle decay aimed at helping to answer the question of why the early universe ended up with an excess of matter. Without that excess, the matter and antimatter created in the Big Bang would have completely annihilated one another.
Imagine the distance between the sun and the star nearest to it—a star called Alpha Centauri. That’s a distance of about 4 light years. Now, imagine as many as 10,000 of our suns crammed into that relatively small space. That is about the density of a galaxy that was recently discovered by an international team of astronomers led by a Michigan State Univ. faculty member.
Since the discovery of the Van Allen radiation belts in 1958, space scientists have believed these belts encircling the Earth consist of two doughnut-shaped rings of highly charged particles. In February of 2013, a team of scientists reported the surprising discovery of a previously unknown third radiation ring. In new research, scientists have successfully modeled and explained the unprecedented behavior of this third ring.
To get a better understanding of the subatomic soup that filled the early universe, and how it “froze out” to form the atoms of today’s world, scientists are taking a closer look at the nuclear phase diagram. Like a map that describes how the physical state of water morphs from solid ice to liquid to steam with changes in temperature and pressure, the nuclear phase diagram maps out different phases of the components of atomic nuclei.
Like the wind adjusting course in the middle of a storm, scientists have discovered that the particles streaming into the solar system from interstellar space have most likely changed direction over the last 40 years. Such information can help us map out our place within the galaxy surrounding us, and help us understand our place in space.
The origin of cosmic rays in the universe has confounded scientists for decades. But a study by researchers using data from the IceCube Neutrino Observatory at the South Pole reveals new information that may help unravel the longstanding mystery of exactly how and where these “rays”, which are actually high-energy particles, are produced.
Physicists have reproduced a pattern resembling the cosmic microwave background radiation in a laboratory simulation of the Big Bang, using ultracold cesium atoms in a vacuum chamber at the Univ. of Chicago. According to the researchers, this is the first time an experiment like this has simulated the evolution of structure in the early universe.
The combined computing power of 200,000 private PCs helps astronomers take an inventory of the Milky Way. The Einstein@Home project connects home and office PCs of volunteers from around the world to a global supercomputer. Using this computer cloud, an international team analyzed archival data to discover 24 pulsars which has been previously missed by astronomers.
An analysis of gravity and topography data from Saturn's largest moon, Titan, has revealed unexpected features of the moon's outer ice shell. The best explanation for the findings, say scientists, is that Titan's ice shell is rigid and that relatively small topographic features on the surface are associated with large roots extending into the underlying ocean.
Astronomers have found a clever new way to slice and dice the flickering light from a distant star in a way that reveals the strength of gravity at its surface. The method could be used to significantly improve estimates of the sizes of the hundreds of exoplanets that have been discovered in the last 20 years.
On Tuesday, the sun erupted with an Earth-directed coronal mass ejection or CME, a solar phenomenon which can send billions of tons of particles into space that can reach Earth one to three days later. These particles cannot travel through the atmosphere to harm humans on Earth, but they can affect electronic systems in satellites and on the ground.
A new theory by fluid dynamics experts at the Univ. of California, Berkeley, shows how “zombie vortices” help lead to the birth of a new star. In a recent report, a UC Berkeley-led team shows how variations in gas density lead to instability, which then generates the whirlpool-like vortices needed for stars to form.
In the time it takes you to complete a single workday, or get a full night’s sleep, a small fireball of a planet 700 light-years away has already completed an entire year. Researchers have discovered an Earth-sized exoplanet named Kepler 78b that whips around its host star in a mere 8.5 hours, one of the shortest orbital periods ever detected.
Carrying Earthly greetings on a gold plated phonograph record and still-operational scientific instruments NASA's Voyager 1 has traveled farther from Earth than any other human-made object. And now, researchers say, it has begun the first exploration of our galaxy beyond the Sun's influence. The finding could be, however, somewhat controversial.
A meteor weighing 10,000 metric tons exploded 14 miles above Chelyabinsk, Russia, on Feb. 15, 2013. Unlike similar past events, this time scientists had the sensitive instruments on the Suomi NPP satellite to deliver unprecedented data and help them track and study the meteor plume for months.
A recent arrival to NASA’s Kennedy Space Center in Florida, the Mars Atmosphere and Volatile Evolution (MAVEN) spacecraft will have quite a different approach than that taken by recent probes dispatched to the Red Planet. Instead of rolling about on the surface looking for clues to the planet's hidden heritage, MAVEN will orbit high above the surface so it can sample the upper atmosphere for signs of what changed over the eons and why.
Astronomers have solved a 40-year-old mystery on the origin of the Magellanic Stream, a long ribbon of gas stretching nearly halfway around our Milky Way galaxy. It appears to originate from two dwarf galaxies, but astronomers did not know if one or both galaxies were the source. Hubble Space Telescope’s Cosmic Origins Spectrograph was used to examine the gas and find the answer.
Using infrared data from the Subaru Telescope in Hawaii, an international team of astronomers has imaged a giant planet around the bright star GJ 504. Several times the mass of Jupiter and similar in size, the new world, dubbed GJ 504b and still glowing from the heat of its formation, is the lowest-mass planet ever detected around a star like the sun using direct imaging techniques.
After studying data from a pair of NASA probes roaming the harsh space environment within the Van Allen radiation belts, researchers at Los Alamos National Laboratory believe they have solved a lingering mystery about how electrons within Earth’s radiation belt can suddenly become energetic enough to kill orbiting satellites.
On July 17, 2013, the international team which supported and built NASA's Interface Region Imaging Spectrograph, or IRIS, was rewarded for its hard work when the door of the telescope opened to view the mysterious lowest layers of the sun's atmosphere in unprecedented detail. Imaging in ultraviolet light and using a spectrograph, the orbiter has already revealed a multitude of previously unseen structures.
Three years of research, led by the Univ. of Leicester in the U.K., has produced a new catalog of x-ray source observations call 3XMM. With the help of the university’s supercomputer, the scientists were able to log 531,261 detections of x-ray emitting objects and 372,728 unique x-ray sources. The catalog will provide a useful dataset for generating large, well-defined samples of celestial objects.
Researchers at Brown Univ. have shown that some Martian valleys appear to have been caused by runoff from orographic precipitation—moisture carried part of the way up a mountain and deposited on the slopes. The new findings are the most detailed evidence yet of an orographic effect on ancient Mars.
After a quarter-century of searching, scientists have nailed down how one particularly rare subatomic particle decays into something else. CERN on Friday it had measured the decay time of a particle known as a Bs (B sub s) meson into two other fundamental particles called muons, which are much heavier than but similar to electrons.