This week I recommend to follow @NASADryden for interesting tweets from NASA’s Dryden Flight Research Center, a center for atmospheric flight research and operations. For more Twitter follow suggestions see our astronomy list @TheAstroBlog/astronomy
Giant Planet Ejected from the Solar System?
Just as an expert chess player sacrifices a piece to protect the queen, the solar system may have given up a giant planet and spared Earth, according to an article recently published in The Astrophysical Journal Letters. “We have all sorts of clues about the early evolution of the solar system,” says author Dr. David Nesvorny of the Southwest Research Institute. “They come from the analysis of the trans-Neptunian population of small bodies known as the Kuiper Belt, and from the lunar cratering record.”
Evidence for ‘Great Lake’ On Europa and Potential New Habitat for Life
In a significant finding in the search for life beyond Earth, scientists from The University of Texas at Austin and elsewhere have discovered what appears to be a body of liquid water the volume of the North American Great Lakes locked inside the icy shell of Jupiter’s moon Europa. The water could represent a potential habitat for life, and many more such lakes might exist throughout the shallow regions of Europa’s shell, lead author Britney Schmidt, a postdoctoral fellow at The University of Texas at Austin’s Institute for Geophysics, writes in the journal Nature.
Birth of Famous Black Hole: Longstanding Mysteries About Object Called Cygnus X-1 Unraveled
For the first time, astronomers have produced a complete description of a black hole, a concentration of mass so dense that not even light can escape its powerful gravitational pull. Their precise measurements have allowed them to reconstruct the history of the object from its birth some six million years ago. Using several telescopes, both ground-based and in orbit, the scientists unravelled longstanding mysteries about the object called Cygnus X-1, a famous binary-star system discovered to be strongly emitting X-rays nearly a half-century ago.
An uncertain future for solar system exploration
Some fear the upcoming launch of NASA’s Mars Science Laboratory mission may be the beginning of the end of the agency’s Mars exploration plans. In less than two weeks, an Atlas V rocket is slated to lift off from Cape Canaveral, propelling NASA’s Mars Science Laboratory (MSL) spacecraft towards the Red Planet. MSL — aka Curiosity — is one of the most ambitious, and expensive, Mars missions ever flown.
Phobos-Grunt could be rerouted to visit an asteroid
Phobos Grunt, the Russian Mars probe that’s been stuck in a precipitously low Earth orbit for a fortnight, has finally been contacted by a European Space Agency ground station in Perth, Australia. It is unclear, however, if this means the craft and its intricate Martian soil-sampling mission can be rescued. The spacecraft was launched from Baikonur, Kazakhstan on 8 November on an ambitious mission to sample soil from the Martian moon Phobos – and return it to Earth.
Magnetic Fields Set Stage for Birth of New Stars
Astronomers at the Max Planck Institute for Astronomy have, for the first time, measured the alignment of magnetic fields in gigantic clouds of gas and dust in a distant galaxy. Their results suggest that such magnetic fields play a key role in channeling matter to form denser clouds, and thus in setting the stage for the birth of new stars. Stars and their planets are born when giant clouds of interstellar gas and dust collapse. You’ve probably seen the resulting stellar nurseries in beautiful astronomical images: Colorful nebulae, lit by the bright young stars they have brought forth.
NASA Extends MESSENGER Mission Orbiting Mercury
NASA has announced that it will extend the MESSENGER mission for an additional year of orbital operations at Mercury beyond the planned end of the primary mission on March 17, 2012. The MESSENGER probe became the first spacecraft to orbit the innermost planet on March 18, 2011. “We are still ironing out the funding details, but we are pleased to be able to support the continued exploration of Mercury,” said NASA MESSENGER Program Scientist Ed Grayzeck, who made the announcement on November 9 at the 24th meeting of the MESSENGER Science Team in Annapolis, Md.
Why the Milky Way May Be Facing a Midlife Crisis
Our Milky Way galaxy and its neighbor, the Andromeda galaxy, seem to be going through a midlife crisis. New research reveals that both galaxies are in the middle of transitioning from young, star-forming regions into older, stagnant ones, a transition that is revealed by the galaxies’ color. Generally, such a change comes after two galaxies collide, astronomers said, but this pair seems to be making the shift on its own. In galaxies, star formation rates and color are closely related. But, analyses of the shade of the Milky Way are surprisingly rare.
Galaxies Are the Ultimate Recyclers, NASA’s Hubble Confirms
Galaxies learned to “go green” early in the history of the universe, continuously recycling immense volumes of hydrogen gas and heavy elements to build successive generations of stars stretching over billions of years. This ongoing recycling keeps galaxies from emptying their “fuel tanks” and therefore stretches out their star-forming epoch to over 10 billion years. However, galaxies that ignite a rapid firestorm of star birth can blow away their remaining fuel, essentially turning off further star-birth activity.
Spectacular New Image Exposes Nebula’s Cool Clouds
A stunning new image of the Carina nebula reveals cold, dusty cosmic clouds where violent and dynamic star formation is taking place. These clouds of dust and gas play host to some of the most massive and luminous stars in our galaxy, which make them scintillating test beds for studying the interactions between these young stars and their parent molecular clouds. The new observations were made with the Atacama Pathfinder Experiment (APEX) telescope, which is located about 16,700 feet (5,100 meters) above sea level at the Llano de Chajnantor Observatory in the Atacama desert in northern Chile.
Voyager 2 Completes Switch to Backup Thruster Set
NASA’s Voyager 2 has successfully switched to the backup set of thrusters that controls the roll of the spacecraft. Deep Space Network personnel sent commands to the spacecraft to make the change on Nov. 4 and received confirmation Nov. 14 that the switch has been made. Voyager 1 and Voyager 2 are each equipped with six sets, or pairs, of thrusters to control the pitch, yaw and roll motions of the spacecraft. These include three pairs of primary thrusters and three backup, or redundant, pairs.
Most Popular Skywatching Misconceptions Explained
With the return of the brilliant planet Venus to our evening sky, I’m reminded of an amusing anecdote related by a good friend of mine, George Lovi, a well-known astronomy lecturer and author who passed away in 1993. One night, while running a public night at the Brooklyn College Observatory in New York, the telescope was pointed right at Venus, which was displaying a delicate crescent shape at the time. Yet, one student gazing through the telescope eyepiece stubbornly insisted that he was really looking at the moon.
Staring into the eyes of the Dragon
Last Wednesday China launched an observation satellite. Although the media has noted that China has launched a lot of rockets in the recent past, they have devoted less attention to what they’ve actually carried. What the rockets have often been carrying are imaging reconnaissance satellites and ocean surveillance satellites, as well as navigation and meteorology satellites. China has been rapidly building up constellations of dual-use and military satellites that extend its military’s ability to operate beyond its own borders, including its ability to monitor the oceans and to spot — and eventually target — US Navy vessels at sea.
Ancient Stars Shed Light On the Prehistory of the Milky Way
Some of Milky Way’s ‘stellar fossils’ — our galaxy’s oldest stars — contain abnormally large amounts of heavy elements like gold, platinum and uranium. Where these large amounts came from has been a mystery for researchers, since they are usually seen in much later generations of stars. Researchers at the Niels Bohr Institute have been studying these ancient stars for several years with ESO’s giant telescopes in Chile in order to trace the origin of these heavy elements and with recent observations they have concluded how they could have been formed in the early history of the Milky Way.
Mysterious Dark Energy Played No More Than Bit Part in Early Universe
Scientists trying to understand dark energy, one of the weirdest things in the universe, have made a step forward in determining how much of it could have existed shortly after the Big Bang. Dark energy is the mysterious force scientists think is responsible for pulling space apart at the seams, causing the expansion of the universe to accelerate. No one knows what dark energy is, and it hasn’t been detected directly.
Potential New NASA Mission Would Reveal the Hearts of Undead Stars
Neutron stars have been called the zombies of the cosmos, shining on even though they’re technically dead, and occasionally feeding on a neighboring star if it gets too close. They are born when a massive star runs out of fuel and collapses under its own gravity, crushing the matter in its core and blasting away its outer layers in a supernova explosion that can outshine a billion suns.
Phobos-Grunt: a legal analysis of potential liability and options for mitigation
For the third time in as many months the potential exists for a large space object to fall out of orbit and impact the surface of the Earth. Unlike the prior two incidents where the space objects involved were derelict research satellites, the space object in question is a probe launched by the Russian Federation on November 9, 2011, destined to travel to Mars. This essay will briefly address some of the legal issues and the potential for mitigating the impact the spacecraft may have when it reenters.
Astronomers Find Clouds of Primordial Gas from the Early Universe, Just Moments After Big Bang
For the first time, astronomers have found pristine clouds of the primordial gas that formed in the first few minutes after the Big Bang. The composition of the gas matches theoretical predictions, providing direct evidence in support of the modern cosmological explanation for the origins of elements in the universe. Only the lightest elements, mostly hydrogen and helium, were created in the Big Bang.
3 New Heavy Elements Named: Darmstadtium, Roentgenium, Copernicium
The periodic table of elements just got a bit heftier today (Nov. 4), as the names of three new elements were approved by the General Assembly of the International Union of Pure and Applied Physics. Elements 110, 111 and 112 have been named darmstadtium (Ds), roentgenium (Rg) and copernicium (Cn). These elements are so large and unstable they can be made only in the lab, and they fall apart into other elements very quickly.
Tarantula Nebula Glows With X-Rays and Infrared Light
The star-forming region, 30 Doradus, is one of the largest located close to the Milky Way and is found in the neighboring galaxy Large Magellanic Cloud. About 2,400 massive stars in the center of 30 Doradus, also known as the Tarantula Nebula, are producing intense radiation and powerful winds as they blow off material. Multimillion-degree gas detected in X-rays (blue) by the Chandra X-ray Observatory comes from shock fronts — similar to sonic booms — formed by these stellar winds and by supernova explosions.
Why Asteroids Make Lousy Space Weapons
If you lie awake at night worrying about some supervillain steering giant asteroids toward your hometown, you really should relax, experts say. It’s not going to happen anytime soon. Humanity does indeed have the technical skills to move space rocks around, and we may employ this know-how at some point to avoid a catastrophic impact like the one that killed the dinosaurs 65 million years ago. But the odds of any rogue state using asteroids to rain death down on its enemies are minuscule, experts say.
Ancient Lunar Dynamo May Explain Magnetized Moon Rocks
The presence of magnetized rocks on the surface of the moon, which has no global magnetic field, has been a mystery since the days of the Apollo program. Now a team of scientists has proposed a novel mechanism that could have generated a magnetic field on the moon early in its history. The “geodynamo” that generates Earth’s magnetic field is powered by heat from the inner core, which drives complex fluid motions in the molten iron of the outer core.
Deflecting Killer Asteroids Away From Earth: How We Could Do It
A huge asteroid’s close approach to Earth tomorrow reinforces that we live in a cosmic shooting gallery, and we can’t just sit around waiting to get hit again, experts say. Asteroid 2005 YU55, which is the size of an aircraft carrier, will zip within the moon’s orbit tomorrow, but it poses no danger of hitting us for the foreseeable future. Eventually, however, one of its big space rock cousins will barrel straight toward Earth, as asteroids have done millions of times throughout our planet’s history.
Lutetia: A Rare Survivor from the Birth of Earth
New observations indicate that the asteroid Lutetia is a leftover fragment of the same original material that formed Earth, Venus and Mercury. Astronomers have combined data from ESA’s Rosetta spacecraft, ESO’s New Technology Telescope, and NASA telescopes. They found that the properties of the asteroid closely match those of a rare kind of meteorites found on Earth and thought to have formed in the inner parts of the Solar System.
Space ‘Superbubbles’ Could Spawn Energetic Cosmic Rays
Enigmatic cosmic rays that strike Earth with giant amounts of energy might come from hot gaseous “superbubbles” in space, a new study reveals. Cosmic rays have perplexed scientists for a century. These electrically charged particles bombard Earth with energies dwarfing anything we are capable of, but their origins remain a mystery. Since cosmic rays are electrically charged, they can get pushed and pulled around by interstellar magnetic fields in the gas between the stars as they zip through space, obscuring where they come from.
2012: Killer Solar Flares Are a Physical Impossibility, Experts Say
Given a legitimate need to protect Earth from the most intense forms of space weather — great bursts of electromagnetic energy and particles that can sometimes stream from the sun — some people worry that a gigantic “killer solar flare” could hurl enough energy to destroy Earth. Citing the accurate fact that solar activity is currently ramping up in its standard 11-year cycle, there are those who believe that 2012 could be coincident with such a flare.
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