Thousands of amateur (ham) radio operators around the world were able to say “Hi” to NASA’s Juno spacecraft Oct. 9 as it swung past Earth on its way to Jupiter.
According to Donald Kirchner, University of Iowa research engineer on Juno and one of the coordinators of the all-volunteer “Say Hi to Juno” project, all licensed amateur radio operators were invited to participate by visiting a website and following posted instructions.
“The idea was to coordinate the efforts of amateur radio operators all over the world, and send a message in Morse code that could be received by the University of Iowa-designed-and-built instrument on the Juno spacecraft,” he says. “We know that over a thousand participated, and probably many more than that.”
The Karl G. Jansky Very Large Array (VLA) will get a new system allowing it to continuously monitor the sky to study the Earth’s ionosphere and detect short bursts of radio emission from astronomical objects. The National Radio Astronomy Observatory (NRAO) and the Naval Research Laboratory (NRL) signed a $1 million contract under which NRL will fund a system to capture data from low-frequency radio receivers mounted on VLA antennas that will allow simultaneous and completely independent operation alongside the VLA’s standard scientific observations.
“This essentially will turn the VLA into two telescopes, working in parallel to perform different types of scientific research simultaneously,” said Dale Frail, NRAO’s Director for New Mexico Operations.
The new system, called VLITE (VLA Ionospheric and Transient Experiment), will tap data from 10 VLA antennas, and is a pathfinder for a proposed larger system called the Low Band Observatory (LOBO) that would equip all 27 antennas of the VLA. “The new system will operate independently of the VLA’s higher-frequency systems, using a separate path for data transmission and processing,” said Paul Ray, NRL’s VLITE system engineer.
NASA has released a natural-color image of Saturn from space, the first in which Saturn, its moons and rings, and Earth, Venus and Mars, all are visible.
The new panoramic mosaic of the majestic Saturn system taken by NASA’s Cassini spacecraft, which shows the view as it would be seen by human eyes, was unveiled at the Newseum in Washington on Tuesday.
Cassini’s imaging team processed 141 wide-angle images to create the panorama. The image sweeps 404,880 miles (651,591 kilometers) across Saturn and its inner ring system, including all of Saturn’s rings out to the E ring, which is Saturn’s second outermost ring. For perspective, the distance between Earth and our moon would fit comfortably inside the span of the E ring.
“In this one magnificent view, Cassini has delivered to us a universe of marvels,” said Carolyn Porco, Cassini’s imaging team lead at the Space Science Institute in Boulder, Colo. “And it did so on a day people all over the world, in unison, smiled in celebration at the sheer joy of being alive on a pale blue dot.”
A team of NASA and international scientists for the first time have gathered a detailed understanding of the effects on Earth from a small asteroid impact.
The unprecedented data obtained as the result of the airburst of a meteoroid over the Russian city of Chelyabinsk on Feb. 15, 2013, has revolutionized scientists’ understanding of this natural phenomenon.
The Chelyabinsk incident was well observed by citizen cameras and other assets. This provided a unique opportunity for researchers to calibrate the event, with implications for the study of near-Earth objects (NEOs) and developing hazard mitigation strategies for planetary defense. Scientists from nine countries have now established a new benchmark for future asteroid impact modeling.
“Our goal was to understand all circumstances that resulted in the shock wave,” said meteor expert Peter Jenniskens, co-lead author of a report published in the journal Science.
The first ever evidence of a comet entering Earth’s atmosphere and exploding, raining down a shock wave of fire which obliterated every life form in its path, has been discovered by a team of South African scientists and international collaborators, and will be presented at a public lecture on Thursday.
The discovery has not only provided the first definitive proof of a comet striking Earth, millions of years ago, but it could also help us to unlock, in the future, the secrets of the formation of our solar system.
“Comets always visit our skies – they’re these dirty snowballs of ice mixed with dust – but never before in history has material from a comet ever been found on Earth,” says Professor David Block of Wits University.
The comet entered Earth’s atmosphere above Egypt about 28 million years ago. As it entered the atmosphere, it exploded, heating up the sand beneath it to a temperature of about 2 000 degrees Celsius, and resulting in the formation of a huge amount of yellow silica glass which lies scattered over a 6 000 square kilometer area in the Sahara. A magnificent specimen of the glass, polished by ancient jewellers, is found in Tutankhamun’s brooch with its striking yellow-brown scarab.
In 2012, Astronomy & Astrophysics published a statistical study of the isotopic records of solar activity, in which Abreu et al. claimed that there is evidence of planetary influence on solar activity. A&A is publishing a new analysis of these isotopic data by Cameron and Schüssler. It corrects technical errors in the statistical tests performed by Abreu et al. They find no evidence of any planetary effect on solar activity.
The Sun is a magnetically active star. Its activity manifests itself as dark sunspots and bright faculae on its visible surface, as well as violent mass ejections and the acceleration of high-energy particles resulting from the release of magnetic energy in its outer atmosphere. The frequency with which these phenomena occur varies in a somewhat irregular activity cycle of about 11 years, during which the global magnetic field of the Sun reverses. The solar magnetic field and the activity cycle originate in a self-excited dynamo mechanism based upon convective flows and rotation in the outer third of the solar radius.
Systematic observations of sunspots since the beginning of the 17th century indicate that solar activity also varies on longer timescales, including periods of very low activity, such as the so-called Maunder minimum between 1640 and 1700.
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Using data from a NASA satellite, scientists have discovered a massive particle accelerator in the heart of one of the harshest regions of near-Earth space, a region of super-energetic, charged particles surrounding the globe and known as the Van Allen radiation belts.
New results from NASA’s Van Allen Probes show the acceleration energy is in the belts themselves. Local bumps of energy kick particles inside the belts to ever-faster speeds, much like a well-timed push on a moving swing. Knowing the location of the acceleration within the radiation belts will help scientists improve predictions of space weather, which can be hazardous to satellites near Earth. The results were published Thursday in the journal Science.
“Until the 1990s, we thought the Van Allen belts were pretty well-behaved and changed slowly,” says Geoff Reeves, lead author on the paper and a radiation belt scientist at Los Alamos National Laboratory in Los Alamos, N.M. “With more and more measurements, however, we realized how quickly and unpredictably the radiation belts change. They are basically never in equilibrium, but in a constant state of change.”