Tag Archives: gravity

Berkeley Lab’s Saul Perlmutter wins Nobel Prize in Physics

By Guest PostOctober 4, 2011Science2011 nobel prize in physics, accelerating expansion of the universe, adam riess, anisotropy of the cosmic microwave background radiation, astrophysicist, berkeley lab, brian schmidt, Chile, dark energy, department of energy, expansion of the universe, france, george smoot iii, gravity, high z supernova search team, international supernova cosmology project, Japan, knowledge, lawrence berkeley national laboratory, mysterious force, nature of dark energy, nobel prize, nobel prize in physics, paul alivisatos, saul perlmutter, spain, supernova cosmology project, supernovae, Sweden, swedish kroner, united kingdom, united states, university of california at berkeley

BERKELEY, CA — Saul Perlmutter, an astrophysicist at the U.S. Department of Energy’s Lawrence Berkeley National Laboratory and a professor of physics at the University of California at Berkeley, has won the 2011 Nobel Prize in Physics “for the discovery of the accelerating expansion of the universe through observations of distant supernovae.” Perlmutter heads the international Supernova Cosmology Project, which pioneered the methods used to discover the accelerating expansion of the universe, and he has been a leader in studies to determine the nature of dark energy.

Perlmutter shares the prize with Brian Schmidt and Adam Riess, leader of the High-z Supernova Search Team and first author of that team’s analysis, respectively, which led to their almost simultaneous announcement of accelerating expansion. (more…)

Exeter Physicist Advances Early Universe Theory

By Guest PostSeptember 25, 2011Scienceastrophysicist, big bang, christoph federrath, ecole normale supérieure de lyon, exoplanet research, france, Galaxy, gilles chabrier, gravity, how the first stars and galaxies formed, magnetic fields, magnetic fields in the intergalactic media, professor gilles chabrier, telescopes, three dimensional computer simulations, university of exeter

*Research by a University of Exeter astrophysicist has helped to explain how the first stars and galaxies formed.*

*Research led by Professor Gilles Chabrier of the University of Exeter suggests that large magnetic fields were generated shortly after the Big Bang and played a key role in the formation of the first stars and galaxies.*

The international team of researchers, headed by Professor Chabrier and Dr Christoph Federrath of the Ecole Normale Supérieure de Lyon (France), used three-dimensional computer simulations to make their discovery. Their simulations show that even under extreme physical conditions, magnetic fields are efficiently amplified by turbulent flows. The findings are now published in the journal Physical Review Letters.

Both the gas between the stars in a galaxy and the medium between galaxies are magnetised. However, little is known so far about how these magnetic fields, which can be seen with telescopes, actually came about. Now, the international research team has proposed an answer. (more…)

NASA’s WISE Mission Captures Black Hole’s Wildly Flaring Jet

By Guest PostSeptember 21, 2011Sciencea w blain, accretion disks, astronomers, black hole called gx 339 4, black holes, blazing jets, center of our galaxy, d m russell, extreme environments around black holes, flaring black hole, gamma rays, gravity, infrared observations, japan aerospace exploration agency, jaxa, jets, magnetic field, NASA, neowise, peter eisenhardt, physics of jets, poshak gandhi, radio waves, s markoff, speed of light, ultra dense collection of matter, wide field infrared survey explorer, wise, xrays

PASADENA, Calif. — Astronomers using NASA’s Wide-field Infrared Survey Explorer (WISE) have captured rare data of a flaring black hole, revealing new details about these powerful objects and their blazing jets.

Scientists study jets to learn more about the extreme environments around black holes. Much has been learned about the material feeding black holes, called accretion disks, and the jets themselves, through studies using X-rays, gamma rays and radio waves. But key measurements of the brightest part of the jets, located at their bases, have been difficult despite decades of work. WISE is offering a new window into this missing link through its infrared observations. (more…)

NASA’s Dawn Spacecraft Enters Orbit Around Asteroid Vesta

By Guest PostJuly 17, 2011Scienceasteroid, asteroid vesta, ceres, charles bolden, dawn, dawn spacecraft, dwarf planet, german aerospace center, gravitational pull, gravity, italian space agency, jet propulsion laboratory, los angeles, main asteroid belt between mars and jupiter, marshall space flight center in huntsville, max planck institute for solar system research, NASA, President Obama, spacecraft, university of california, vesta

PASADENA, Calif. — NASA’s Dawn spacecraft on Saturday became the first probe ever to enter orbit around an object in the main asteroid belt between Mars and Jupiter.

Dawn will study the asteroid, named Vesta, for a year before departing for a second destination, a dwarf planet named Ceres, in July 2012. Observations will provide unprecedented data to help scientists understand the earliest chapter of our solar system. The data also will help pave the way for future human space missions. (more…)

NASA Telescope Helps Confirm Nature of Dark Energy

By Guest PostMay 20, 2011Science3 d map, albert einstein, anglo australian telescope, australia, big bang, caltech, chris blake, christopher martin, constant force, cosmic time, dark energy, dark matter, galaxies, galaxy evolution explorer, gravitational attractions, gravity, how dark energy works, jon morse, melbourne, NASA, siding spring mountain, swinburne university of technology, universe

PASADENA, Calif. — A five-year survey of 200,000 galaxies, stretching back seven billion years in cosmic time, has led to one of the best independent confirmations that dark energy is driving our universe apart at accelerating speeds. The survey used data from NASA’s space-based Galaxy Evolution Explorer and the Anglo-Australian Telescope on Siding Spring Mountain in Australia.

The findings offer new support for the favored theory of how dark energy works — as a constant force, uniformly affecting the universe and propelling its runaway expansion. They contradict an alternate theory, where gravity, not dark energy, is the force pushing space apart. According to this alternate theory, with which the new survey results are not consistent, Albert Einstein’s concept of gravity is wrong, and gravity becomes repulsive instead of attractive when acting at great distances. (more…)

Spacecraft will Enable Scientists to Study Space Environment around Moon, Earth

By Guest PostNovember 2, 20102 commentsScienceacceleration, artemis, artemis spacecraft, aurora borealis, earth, electrodynamics, Environment, events, gravity, lunar environment, macroscale interactions, magnetic field, mission, moon environment, NASA, particle acceleration, reconnection, satellites, Space, spacecraft, substorms, sun-earth-moon, themis, time history, turbulence, vassilis angelopoulos

Two spacecraft are now beginning to study the moon’s environment as part of NASA’s ARTEMIS mission, whose principal investigator is Vassilis Angelopoulos, a UCLA professor of Earth and space sciences.

One of these satellites has been in the lunar environment since Aug. 25, and the second arrived Oct. 22, marking the start of the ARTEMIS mission to gather new scientific data in the sun-Earth-moon environment.

About the image: An artist’s rendering of the two ARTEMIS spacecraft in the lunar environment. Image credit: NASA/SVS (more…)

Intricate, Curving 3D Nanostructures Created Using Capillary Action Forces

By Guest PostOctober 20, 2010Science3d, 3d nanotube structures, a john hart, acetone condense, aircraft, bending petals, capillary action, capillary forming, carbon nanotubes, concentric rings, drinking straw, evaporate, gravity, john hart, liquids, microdevices, miniature, phenomenon, spacecraft, three-dimensional, twisting spires, university of michigan

Twisting spires are one of the 3D shapes researchers at the University of Michigan were able to develop using a new manufacturing process. Image credit: A. John Hart

ANN ARBOR, Mich

.— Twisting spires, concentric rings, and gracefully bending petals are a few of the new three-dimensional shapes that University of Michigan engineers can make from carbon nanotubes using a new manufacturing process.

The process is called “capillary forming,” and it takes advantage of capillary action, the phenomenon at work when liquids seem to defy gravity and spontaneously travel up a drinking straw.

The new miniature shapes have the potential to harness the exceptional mechanical, thermal, electrical, and chemical properties of carbon nanotubes in a scalable fashion, said A. John Hart, an assistant professor in the Department of Mechanical Engineering and in the School of Art & Design.

The 3D nanotube structures could enable countless new materials and microdevices, including probes that can interface with individual cells, novel microfluidic devices, and lightweight materials for aircraft and spacecraft. (more…)

Eyjafjallajokull

By PravdaApril 19, 2010Scienceecological catastrophe, eyjafjallajökull, fluoride gas, gravity, iceland-mountains glacier, Icelandic volcano, katla volcano, laki, maria neira, NASA, newtonwise, particulate, sulphur dioxide, terra satellite, volcanic plume, world health organization

Eyjafjallajökull. While some say it is “unpronounceable”, it would be a good idea to get used to the name because for sure it is going to be around the international media for a long time to come.

(more…)