NASA’s WISE mission has tracked down 93 percent of the 1 kilometer diameter or larger asteroids whose size could devastate our planet. The project’s asteroid census has revised the total number of NEO’s down from 36,000 to 20,500.
Physics Nobel Explainer: Why Is Expanding Universe Accelerating?
More than a decade after prize-worthy find, dark energy still baffles.
What goes up must come down. Few on Earth would argue with the fundamental law of gravity. But today the 2011 Nobel Prize in Physics was awarded to three scientists who uncovered a dark side of the force.
The finding led to the now widely accepted theory of dark energy, a mysterious force that repels gravity. Measurements show that dark energy accounts for about 74 percent of the substance of the universe.
Dense knots of dust in otherwise normal galaxies dim the light of a dark gamma-ray burst. The dust absorbs most or all of a burst’s visible light but not higher-energy X-rays and gamma rays. Credit NASA/Swift/Aurore Simonnet
The Great Nebula in Orion is a colorful place. Visible to the unaided eye as a fuzzy patch in the constellation of Orion, this image taken with the Big Throughput Camera shows the Orion Nebula to be a busy neighborhood of young stars, hot gas, and dark dust.
Reality Catches Up With Fiction: First Planet Discovered that Orbits Two Suns at Once
Sometimes the orange sun rises first. Sometimes it is the red one, although they are never far apart in the sky and you can see them moving past each other, casting double shadows across the firmament and periodically crossing right in front of each other.
The official name of the new planet is Kepler 16b, but astronomers are already referring to it informally as Tatooine, after the home planet of Luke and Anakin Skywalker in the George Lucas “Star Wars” movies, which also had two suns.
“Reality has finally caught up with science fiction,” said Alan P. Boss of the Carnegie Institution, a member of the research team.
Scientists provided new insights into a cosmic accident that has been streaming X-rays toward Earth since March. Two studies appearing in the Aug. 25 issue of the journal Nature revealed the information about the accident.
NASA’s Swift satellite first alerted astronomers to intense and unusual high-energy flares from the new source in the constellation Draco.
“Incredibly, this source is still producing X-rays and may remain bright enough for Swift to observe into next year,” said David Burrows, professor of astronomy at Penn State University and lead scientist for the mission’s X-Ray Telescope instrument. “It behaves unlike anything we’ve seen before.”
Astronomers soon realized the source, known as Swift J1644+57, was the result of a truly extraordinary event — the awakening of a distant galaxy’s dormant black hole as it shredded and consumed a star. The galaxy is so far away, it took the light from the event approximately 3.9 billion years to reach Earth.
As if the idea ideas of quantum entanglement and time travel weren’t difficult enough to wrap one’s head around separately, two physicists at the Universtiy of Queensland in Australia have further compounded the headache by merging the two ideas via a new kind of quantum entanglement that links particles not across space, but across time.
Quantum entanglement is that “spooky action” (Einstein’s words, not ours) that links two particles such that a measurement on one immediately influences the state of the other, even if the two particles are separated by miles, or even light years. Entanglement defies the intuitive way we understand the universe to work (as does most of quantum mechanics). The idea of “time teleportation,” as described by S. Jay Olson and Timothy Ralph, doesn’t add clarity but it does introduce some interesting questions about the fundamentals of the universe.
“The idea is that a detector acts on a qubit and then generates a classical message describing how this particle can be detected. Then, at some point in the future, another detector at the same position in space, receives this message and carries out the required In a sense, everyone and everything is time traveling, moving forward in time at a given rate. What Olson and Ralph propose is that it’s possible to take a shortcut into the future without being present in the interim. How? Tech Review’s KFC explains:
This infrared image from NASA’s Wide-field Infrared Survey Explorer (WISE), shows that some gas clouds are so cool and thick that even infrared can’t penetrate them. The clouds colored green, yellow and red are only seen in infrared. However, the black areas in this image — called infrared dark clouds (IRDCs) — are exceptionally cold, dense cloud cores seen in silhouette against the bright diffuse infrared glow of the plane of the Milky Way. The density in these clouds is high enough to lead to the formation of new stars and planets.