The largest sunspot observed on the sun in more than 20 years has been firing off powerful solar flares for the past week, and it's still producing strong solar storms.
Today, the huge sunspot erupted with a large solar flare, peaking at around 10:47 a.m. EDT (1447 GMT).
The flare caused a strong radio blackout on Earth, according to the National Weather Service's Space Weather Prediction Center. This solar flare is the fourth X-flare (the most powerful kind of solar storms) in as many days.
On Sunday (Oct. 26), the giant sunspot unleashed a solar flare, which peaked at about 6:56 a.m. EDT (1056 GMT). The sunspot, called Active Region 12192 (also known as AR 2192), also shot out another powerful flare on Saturday. Today and Sunday's flares measured in at X2, while Saturday's is classified as an X1 flare.
Sunday's X2-class flare was "the third X-class flare in 48 hours, erupting from the largest active region seen on the sun in 24 years," NASA spokesperson Karen Fox wrote in an update yesterday (Oct. 26). AR 2129 also shot out an X3.1-class flare on Friday (Oct. 24).
The sun unleashed an X2-class solar flare on Oct. 26, 2014. NASA's Solar Dynamics Observatory captured this photo of the flare (lower right). Credit: NASA/SDO
A nearby star is not acting its age, thanks to the influence of a massive exoplanet.
The close-orbiting alien planet, known as WASP-18b, is apparently disrupting the magnetic field of its host star so much that the object is behaving like a much older star, researchers said.
"It is one of the most massive hot Jupiters known and one of the closest to its host star, and these characteristics lead to unexpected behaviour. The planet is causing its host star to act old before its time."
Artist's concept depicting the giant alien planet WASP-18b and its star, which are about 330 light-years away. Credit: NASA/CXC/M. Weiss
The star WASP-18, which lies about 330 light-years away, is about as massive as our own sun.
The gas giant WASP-18b weighs in at more than 10 times the mass of Jupiter and completes one orbit around the star in less than 23 hours, leading scientists to classify it as a "hot Jupiter."
WASP-18b's tight orbit has led scientists to estimate that it may have only one million years of life or so remaining before it's destroyed by the parent star.
Young stars tend to be more active, with stronger magnetic fields, larger flares and more intense X-ray emission.
Stellar activity is connected to rotation, a process that slows with age.
Observations of WASP-18 using Chandra revealed no X-ray emission.
This by itself would suggest that the star has an age similar to the sun's 5 billion years, researchers said.
However, Pillitteri and his team used other data as well as theoretical models to calculate that WASP-18 is actually just 500 million to 2 billion years old, and thus approximately 100 times less active than a star its age should be.
Clouds cruise through the skies of Saturn's largest moon, Titan, in striking new imagery captured by NASA's Cassini spacecraft.
In a rare sight for scientists, Cassini captured views of methane clouds drifting across Ligeia Mare, a big hydrocarbon sea near Titan's north pole, from July 20 through July 22.
Few clouds had been seen on Titan since the dissipation of a major storm in 2010, so researchers are trying to gauge the significance of the new observations.
"We're eager to find out if the clouds' appearance signals the beginning of summer weather patterns, or if it is an isolated occurrence," Cassini imaging team associate Elizabeth Turtle, of the Johns Hopkins University Applied Physics Lab in Laurel, Maryland, said in a statement.
"Also, how are the clouds related to the seas? Did Cassini just happen catch them over the seas, or do they form there preferentially?"
NASA's Cassini spacecraft viewed renewed cloud activity in Titan's northern polar region. Image taken on July 21, 2014. Credit: NASA /JPL-Caltech /Space Science Institute
The clouds' motion suggests wind speeds of about 7 to 10 mph (11 to 16 km/h), researchers said.
Saturn and its many moons take 30 years to complete one lap around the sun, so seasons in the Saturn system each last a little more than seven years.
It is now summer in Titan's northern hemisphere; the moon's summer solstice, which marks the midpoint of the season, comes in 2017. Titan, at 3,200 miles (5,150 kilometers) across, is about 50 percent larger than Earth's moon.
Modeling work had suggested that cloud formation should have increased in Titan's northern regions as summer took hold and temperatures rose, but such predictions have not been borne out to date, researchers said.
Titan is the only body in the solar system besides Earth known to possess stable bodies of liquid on its surface. Unlike Earth, however, Titan's climate system is hydrocarbon-based, with methane rain flowing into seas and lakes on the frigid moon's surface.
The $3.2 billion Cassini mission launched in 1997 and began orbiting Saturn in 2004, at the height of the gas giant's northern winter.
Cassini's long life is allowing researchers to track seasonal changes in the Saturn system; the probe is currently scheduled to operate through September 2017, when it will make an intentional death plunge into the ringed planet's thick atmosphere.
That final, fatal maneuver will ensure that Cassini does not contaminate Titan or Enceladus, two Saturn moons that may be capable of supporting life.
Cassini imaged the Titan clouds last month as it sped away from the satellite after a close flyby. Another encounter with Titan is planned for Aug. 21.
Infrared light data gathered by NASA's Spitzer Space Telescope shows that these bursts of particles create shock waves, similar to sonic booms, when they strike the main disk of the galaxy.
The shock waves heat up huge pockets of hydrogen gas to thousands of degrees.
Spiral Galaxy Messier 106
Spiral Galaxy Messier 106 has two extra swirling arms that glow in X-ray, optical and radio light. Credit: X-ray: NASA /CXC /Caltech /P.Ogle et al; Optical: NASA /STScI; IR: NASA /JPL-Caltech; Radio: NSF /NRAO /VLA
The new composite image released by NASA earlier this month shows X-rays seen by NASA's Chandra X-Ray Observatory in blue; radio waves captured by the NSF's Karl Janksy Very Large Array are shown in purple; visible light data from the Hubble telescope can be seen in yellow and blue; and infrared light from the Spitzer telescope in red.
Chandra X-Ray images reveal huge, superheated gas bubbles above and below the plane of the galaxy.
This suggests that much of the gas inside the galaxy is heated to millions of degrees and then rides along the shock waves streaming from the black hole to the outer regions of the galaxy.
Researchers predict all the gas from the galaxy will be cast out within the next 300 million years unless it is somehow replenished. Since most of the gas is already gone, less gas is available for star formation.
Researchers using Spitzer estimate that stars are forming in Messier 106 almost 10 times more slowly than they are in the Milky Way.
The black hole at the center of Messier 106 is about 10 times larger than the black hole in the Milky Way and is sucking in material much more quickly.
A large asteroid shaped like a cosmic peanut zipped safely by Earth this month, and a new NASA video retells the entire space rock encounter as it happened using impressive radar images.
Scientists using NASA's Deep Space Network Goldstone antenna in California tracked the near-Earth asteroid 2006 DP14 using radar imaging as the space rock passed within 2.6 million miles (4.2 million kilometers) of our planet on Feb. 12.
The new radar images show that 2006 DP14 is about 1,300 feet long (400 meters) and 660 feet wide (200 m).
The asteroid is known as a "contact binary" because the two halves of its peanut shape seem to be touching and moving through space together.
2006 DP14 made its closest approach to Earth on Feb. 10 when it traveled about 1.5 million miles (2.4 million km) from the planet's surface, NASA officials said.
Scientists then observed the asteroid on Feb. 12 from 12:03 a.m. EST to 2:27 a.m. EST (0503 GMT to 0727 GMT).
"Radar is a powerful technique for studying an asteroid's size, shape, rotation state, surface features and surface roughness, and for improving the calculation of asteroid orbits," NASA representatives wrote in a statement.
"Radar measurements of asteroid distances and velocities often enable computation of asteroid orbits much further into the future than if radar observations weren't available."
Earlier studies have shown that about 10 percent of near-Earth asteroids larger than 650 feet (200 m) have contact binary shapes, NASA officials said.
Comets and asteroids are considered near-Earth objects (NEOs) of they fly within about 28 million miles (45 million km) of Earth's orbital distance, NASA officials have said.
The sun's magnetic field is poised to reverse its polarity. The effects of the event will be closely monitored by Stanford solar physicists. Credit: Kurt Hickman
The sun's magnetic field is poised to reverse its polarity. The effects of the event, which occurs every 11 years, will ripple throughout the solar system and be closely monitored by Stanford solar physicists.
Every 11 years, the sun undergoes a complete makeover when the polarity of its magnetic field – its magnetic north and south – flips. The effects of this large-scale event ripple throughout the solar system.
Although the exact internal mechanism that drives the shift is not entirely understood, researchers at Stanford's Wilcox Solar Observatory have monitored the sun's magnetic field on a daily basis since 1975 and can identify the process as it occurs on the sun's surface. This will be the fourth shift the observatory has monitored.
New polarity builds up throughout the 11-year solar cycle as sunspots – areas of intense magnetic activity – appear as dark blotches near the equator of the sun's surface.
Over the course of a month, a sunspot spreads out, and gradually that magnetic field migrates from the equator to one of the sun's poles.
As the polarity moves toward the pole, it erodes the existing, opposite polarity, said Todd Hoeksema, a solar physicist at Stanford since 1978 and director of the Wilcox Solar Observatory.
The magnetic field gradually reduces toward zero, and then rebounds with the opposite polarity.
"It's kind of like a tide coming in or going out," Hoeksema said. "Each little wave brings a little more water in, and eventually you get to the full reversal."
The effects of this event are widespread: The area of space where the sun's magnetic field exerts its influence – called the heliosphere – stretches well beyond Pluto, past NASA's Voyager probes near the edge of interstellar space.
The sun is also typically at the peak of its activity during a magnetic field reversal, which, in addition to an increased number of sunspots, is marked by a surge in solar flares and mass ejections.
The sun's changing magnetic field and the bursts of charged particles can interact with Earth's own magnetic field, one manifestation of which is a noticeable uptick in the occurrence and range of auroras.
Earth's magnetic field can also affect major electronic systems, Hoeksema said, such as power distribution grids and GPS satellites, so scientists are keen to monitor the heliosphere.
"We also see the effects of this on other planets," Hoeksema said. "Jupiter has storms, Saturn has auroras, and this is all driven by activity of the sun."
ESA's Mars Express orbited the Red Planet nearly 12,500 times by October 2013. Its high resolution stereo camera images, assembled in this "fly-around," show riverbeds, volcanoes, canyons and craters.
Credit: ESA / DLR / FU Berlin (G. Neukum)
This is the remnant of Kepler's supernova, the famous explosion that was discovered by Johannes Kepler in 1604. The red, green and blue colors show low, intermediate and high energy X-rays observed with NASA's Chandra X-ray Observatory, and the star field is from the Digitized Sky Survey. CREDIT: X-ray: NASA/CXC/NCSU /M.Burkey
Scientists have conducted a postmortem exam on the last gigantic star explosion ever observed by the naked eye in our galaxy, revealing that the supernova was triggered by a compact white dwarf containing more heavy elements than the sun.
The supernova suddenly appeared in the night sky in 1604. Brighter than all other stars and planets at its peak, it was observed by German astronomer Johannes Kepler, who thought he was looking at a new star. Centuries later, scientists determined that what Kepler saw was actually an exploding star, and they named it Kepler's supernova.
The recent cosmic autopsy — made possible by X-ray observations from the Japan-led Suzaku satellite — could help scientists better understand phenomena known as Type Ia supernovae.
"Kepler's supernova is one of the most recent Type Ia explosions known in our galaxy, so it represents an essential link to improving our knowledge of these events," Carles Badenes, an assistant professor of physics and astronomy at the University of Pittsburgh, said in a statement from NASA.
Type Ia supernovae are thought to originate from binary systems where one at least one star is a white dwarf — a tiny, superdense core of a star that has ceased undergoing nuclear fusion reactions.
Gas transferred from a "normal" star in the pair may accumulate on the white dwarf, or if both stars in the system are white dwarfs, their orbits around each other may shrink until they fuse together.
In either case, when the white dwarf or white dwarf conglomerate puts on too much weight (around 1.4 times the sun's mass), a runaway nuclear reaction begins inside, eventually leading to a brilliant supernova.
Last year, Belarus and Russian astronomers Vitaly Nevsky(Belarus) and Artyom Novichonok(Russia), in the ISON-Kislovodsk observatory in Russia, discovered a new gigantic sungrazing comet that is currently approaching Earth.
C/2012 S1 or the ISON comet, which is expected to become brighter than the full moon, will be visible to the naked eye by late 2013.
The astronomers say that given the comet's unique orbit, its origin may be the Oort Cloud, a cluster of frozen rocks and ices surrounding the solar system, located almost a light-year from the Sun.
The comet is currently passing outside Jupiter, gaining speed and becoming brighter by the day. In September 2012, the Russian astronomers spotted what appeared to be a comet in images taken by a telescope that is part of the worldwideInternational Scientific Optical Network ( ISON), from which the object draws its name.
Thanks to ISON, astronomers can get images taken by remote telescopes in other countries, including in New Mexico, where a Russian automatic observatory is located.
The ISON comet never plunged into the inner solar system, and its surface darkened because of the impact of galactic particles. At the same time, the comet avoided being damaged by the so-called solar wind, which is not the case for the Moon, for example.
Sergei Smirnov, press secretary of the Pulkovo Astronomical Observatory in Russia, says that studying surface of the ISON comet may shed more light on evolution of the Universe.
"In the future, it would be good to have special space vehicles on standby so that they can approach such celestial objects, something that may finally come true given the ongoing development of air navigation," Smirnov says.
Thus far, Comet ISON has only been visible through powerful telescopes. In November 2013, heat from the sun will vaporize ices in the comet's body, creating what could be a spectacular tail that will be visible in Earth's night sky without telescopes or even binoculars from about October 2013 through January 2014.
Posts
