Terry's Astronomy Thread.

[Bluearrowll]

Re: Terry's Astronomy Thread.

Daily Suspicious0bserver's Weather Post:
September 15, 2014

What's in the sky tonight?
September 15, 2014

-Last-quarter Moon (exactly last-quarter at 10:05 p.m. EDT). The Moon rises around midnight tonight under the horn-tips of Taurus. It stands high in the south over Orion by Tuesday's dawn.

-Another CME is en route to Earth. It was launched in our direction three days ago by the eruption of a magnetic filament near the center of the solar disk. The impact won't be as effective as the double-whammy of Sept. 12th, described below. Nevertheless, NOAA forecasters estimate a 40% chance of polar geomagnetic storms on Sept. 16th when the CME arrives. High-latitude sky watchers should remain alert for auroras.

-At the peak of the September 11-12 storm, observers in Scandinavia witnessed stunning coronas and even a rare aurora-rainbow ensemble. A hint of auroras were even photographed in Arizona. The below image was taken by Kjetil Skogli of Tromsų Norway. His comments: "During a workshop I had for group of photographers we experienced a rare combination late evening. Northern lights above a rainbow. It was rainy in the lower part of a valley and we had the moon behind us. The rainbow stayed there for hours. For me this was the third time I experienced this during my 11 years as a Aurora photographer Every time it has been in the same valley." Link to image: http://spaceweathergallery.com/indiv...load_id=101791

Astro Picture of the Day:
September 15, 2014

Source:
Spacecraft Rosetta continues to approach, circle, and map Comet Churyumov-Gerasimenko. Crossing the inner Solar System for ten years to reach the vicinity of the comet last month, the robotic spacecraft continues to image the unusual double-lobed comet nucleus. The reconstructed-color image featured, taken about 10 days ago, indicates how dark this comet nucleus is. On the average, the comet's surface reflects only about four percent of impinging visible light, making it as dark as coal. Comet 67P/Churyumov–Gerasimenko spans about four kilometers in length and has a surface gravity so low that an astronaut could jump off of it. In about two months, Rosetta is scheduled to release the first probe ever to attempt a controlled landing on a comet's nucleus.

[Bluearrowll]

Re: Terry's Astronomy Thread.

Daily Suspicious0bserver's Weather Post:
September 16, 2014

What's in the sky tonight?
September 16, 2014

-Solar activity is low. However, sunspots AR2157, AR2158 and AR2164 have 'beta-gamma' magnetic fields that harbor energy for significant eruptions. NOAA forecasters estimate a 50% chance of M-class flares on Sept. 16th.

Astro Picture of the Day:
September 16, 2014

Source:
Galaxies, stars, and a serene reflecting pool combine to create this memorable land and skyscape. The featured panorama is a 12-image mosaic taken last month from the Salar de Atacama salt flat in northern Chile. The calm water is Laguna Cejar, a salty lagoon featuring a large central sinkhole. On the image left, the astrophotographer's fiancee is seen capturing the same photogenic scene. The night sky is lit up with countless stars, the Large and Small Magellanic Cloud galaxies on the left, and the band of our Milky Way galaxy running diagonally up the right. The Milky Way may appear to be causing havoc at the horizon, but those are just the normal lights of a nearby town.

[Bluearrowll]

Re: Terry's Astronomy Thread.

Daily Suspicious0bserver's Weather Post:
September 17, 2014

What's in the sky tonight?
September 17, 2014

-A slow-moving CME propelled toward Earth by an erupting magnetic filament on the sun is expected to arrive today, Sept. 17th. NOAA forecasters estimate a 50% chance of minor geomagnetic storms in response to the sluggish impact. High-latitude sky watchers, be alert for auroras.

-On Sept. 12th, a CME hit Earth's magnetic field, igniting the most intense geomagnetic storm of the year. The students of Earth to Sky Calculus quickly launched a helium balloon to the stratosphere to see what effect the storm was having on Earth's upper atmosphere. They expected to measure more radiation than usual. Instead, they measured less. This plot shows a sharp drop in high energy radiation on Sept. 12th compared to previous flights in May, June, and August.

What caused this counterintuitive drop? Answer: When the CME swept past Earth, it swept aside many of the cosmic rays that normally surround our planet. The effect is called a "Forbush Decrease," after American physicist Scott F. Forbush who first described it.

Wherever CMEs go, cosmic rays are deflected by magnetic fields inside the CME. Forbush decreases have been observed on Earth and in Earth orbit onboard Mir and the ISS. The Pioneer 10 and 11 and Voyager 1 and 2 spacecraft have experienced them, too, beyond the orbit of Neptune. Now high school students have detected a Forbush Decrease in the stratosphere using little more than an insulated lunchbox and a helium balloon.

The balloon's lunchbox-payload is shown here suspended almost 110,000 feet above the Sierras of central California.

Inside the payload, there was a high-energy radiation sensor, a cryogenic thermometer, multiple GPS altimeters and trackers, and three cameras. During the 2.5 hour flight, the buoy collected more than 50 gigabytes of video and science data ranging in altitude from 8500 ft to 113,700 ft above sea level. The analysis is still underway.

The students wish to thank Caisson Biotech LLC for sponsoring this flight. Note their logo on the upper right corner of the payload!

-If you would like to sponsor an upcoming balloon launch, support the next generation of scientists, and have your logo flown to the edge of space, please contact Dr. Tony Phillips to make arrangements. The cost of sponsorship is $500. Sponsors receive a complete video of the flight along with advertising exposure on spaceweather.com.

Email:

[email protected]

Astro Picture of the Day:
September 17, 2014

Source:
It has been a good week for auroras. Earlier this month active sunspot region 2158 rotated into view and unleashed a series of flares and plasma ejections into the Solar System during its journey across the Sun's disk. In particular, a pair of Coronal Mass Ejections (CMEs) impacted the Earth's magnetosphere toward the end of last week, creating the most intense geomagnetic storm so far this year. Although power outages were feared by some, the most dramatic effects of these impacting plasma clouds were auroras seen as far south as Wisconsin, USA. In the featured image taken last Friday night, rays and sheets of multicolored auroras were captured over Acadia National Park, in Maine, USA. Since another CME plasma cloud is currently approaching the Earth, tonight offers another good chance to see an impressive auroral display.

[Bluearrowll]

Re: Terry's Astronomy Thread.

Daily Suspicious0bserver's Weather Post:
September 18, 2014

What's in the sky tonight?
September 18, 2014

-A minor CME expected to hit Earth's magnetic field on Sept. 17th apparently did not. Either it sailed wide of our planet or its impact was too puny to detect. With no CME to rattle Earth's magnetic field, NOAA forecasters have downgraded the chances of a geomagnetic storm today to only 20%.

-Iceland's largest volcano is restless. The Bardarbunga volcano system, located under the massive Vatnajoekull glacier, has been rocked by hundreds of tremors daily since mid-August. Lava is currently spewing from fissures, prompting fears of a much larger eruption. Local photographers, meanwhile, are having a great time recording a rare mix of lava-red and aurora-green in the night sky. Thorsten Boeckel sends this photo from Mżvatn, Iceland. "The red shine of the fissure eruption together with the green aurora provided a phantastic view," he says.

A full-fledged eruption of this volcano has the potential to be even more disruptive than the 2010 eruption of nearby Eyjafjallajokull, which threw air traffic into chaos across Europe. According to the Icelandic Met Office, there are no signs of decreasing magma output as of Sept. 17th. This means more lava is in the offing--along with more phantastic photo-ops as aurora season unfolds around the Arctic Circle.

Astro Picture of the Day:
September 18, 2014

Source:
In this crowded starfield covering over 2 degrees within the high flying constellation Cygnus, the eye is drawn to the Cocoon Nebula. A compact star forming region, the cosmic Cocoon punctuates a long trail of obscuring interstellar dust clouds. Cataloged as IC 5146, the nebula is nearly 15 light-years wide, located some 4,000 light years away. Like other star forming regions, it stands out in red, glowing, hydrogen gas excited by the young, hot stars and blue, dust-reflected starlight at the edge of an otherwise invisible molecular cloud. In fact, the bright star near the center of this nebula is likely only a few hundred thousand years old, powering the nebular glow as it clears out a cavity in the molecular cloud's star forming dust and gas. But the long dusty filaments that appear dark in this visible light image are themselves hiding stars in the process of formation that can be seen seen at infrared wavelengths.

[Bluearrowll]

Re: Terry's Astronomy Thread.

Daily Suspicious0bserver's Weather Post:
September 19, 2014

What's in the sky tonight?
September 19, 2014

-No geomagnetic storm was in the forecast for Sept. 19th, but a storm occurred anyway. Sky watchers around the Arctic Circle saw the midnight sky turn green as magnetometers registered an unexpected G1-class disturbance between 0300 and 0600 UT. "Suddenly there were lots of Northern Lights above the Lofoten Islands of Norway," reports Eric Fokke, who put his camera on the ground to record the display through a patch of mushrooms.

"Unfortunately there was no Moon to illuminate the mushroms, so I had to take this picture under streetlights," says Fokke. "The auroras were bright enough to see despite the manmade glare."

The source of the display was a fluctuation in the interplanetary magnetic field (IMF). During the early hours of Sept. 19th, the IMF tipped south, opening a crack in our planet's magnetosphere. Solar wind poured in to fuel the storm.

NOAA forecasters estimate a 20% chance of more polar geomagnetic storms tonight. In other words, if you're an Arctic photographer, there's a 1 in 5 chance you should find a pumpkin patch.

Astro Picture of the Day:
September 19, 2014

Source:
For astrobiologists, these may be the four most tantalizing moons in our Solar System. Shown at the same scale, their exploration by interplanetary spacecraft has launched the idea that moons, not just planets, could have environments supporting life. The Galileo mission to Jupiter discovered Europa's global subsurface ocean of liquid water and indications of Ganymede's interior seas. At Saturn, the Cassini probe detected erupting fountains of water ice from Enceladus indicating warmer subsurface water on even that small moon, while finding surface lakes of frigid but still liquid hydrocarbons beneath the dense atmosphere of large moon Titan. Now looking beyond the Solar System, new research suggests that sizable exomoons, could actually outnumber exoplanets in stellar habitable zones. That would make moons the most common type of habitable world in the Universe.

[Bluearrowll]

Re: Terry's Astronomy Thread.

Daily Suspicious0bserver's Weather Post:
September 20, 2014

What's in the sky tonight?
September 20, 2014

-Although the sun is peppered with spots, not one them has the type of complex magnetic field that harbors energy for strong explosions. NOAA forecasters estimate a slight 20% chance of M-class solar flares during what should be a quiet weekend.

-In bright twilight, Mercury and fainter Spica are in conjunction 0.6° apart just above the west-southwest horizon. Use binoculars to scan for them about 20 minutes after sunset.

The eclipsing variable star Algol (Beta Persei) should be at its minimum light, magnitude 3.4 instead of its usual 2.1, for a couple of hours centered on 10:55 p.m. EDT.

In early dawn on Sunday the 21st, the waning crescent Moon shines far below Jupiter and closer to the right of Regulus, as shown below.

Astro Picture of the Day:
September 20, 2014

Source:
Against dark rifts of interstellar dust, the ebb and flow of starlight along the Milky Way looks like waves breaking on a cosmic shore in this night skyscape. Taken with a digital camera from the dunes of Hatteras Island, North Carolina, planet Earth, the monochrome image is reminiscent of the time when sensitive black and white film was a popular choice for dimmly lit night- and astro-photography. Looking south, the bright stars of Sagittarius and Scorpius are near the center of the frame. Wandering Mars, Saturn, and Zubenelgenubi (Alpha Librae) form the compact triangle of bright celestial beacons farther right of the galaxy's central bulge. Of course, the evocative black and white beach scene could also be from that vintage 1950s scifi movie you never saw, "It Came From Beyond the Dunes."

[Dronak]

Re: Terry's Astronomy Thread.

I was just stopping by when I came across this thread. Cool idea. FWIW, I've got a PhD in astronomy. That doesn't make me an expert in every area of the field though, and I'm not currently working in the field (I try to keep up, but it can be tough), but I can try to answer questions and such if you have them. Just note that I'm not a regular visitor here anymore, so responses might take a while. If you want to make sure I see something, sending a PM should give me an e-mail notification, so I'll know to check here. Thanks, and I'm glad to see the general interest in astronomy here!

[Bluearrowll]

Re: Terry's Astronomy Thread.

I was just stopping by when I came across this thread. Cool idea. FWIW, I've got a PhD in astronomy. That doesn't make me an expert in every area of the field though, and I'm not currently working in the field (I try to keep up, but it can be tough), but I can try to answer questions and such if you have them. Just note that I'm not a regular visitor here anymore, so responses might take a while. If you want to make sure I see something, sending a PM should give me an e-mail notification, so I'll know to check here. Thanks, and I'm glad to see the general interest in astronomy here!

That's awesome to hear, I will definitely be in contact with you, cheers! Always nice to see people in the field.


Daily Suspicious0bserver's Weather Post:
September 21, 2014

What's in the sky tonight?
September 21, 2014

-On Sept. 23th the sun will cross the celestial equator heading south, marking the end of northern summer. That's good news for high-latitude sky watchers because, for reasons researchers do not fully understand, auroras love equinoxes. At this time of year when the seasons are changing, even gentle gusts of solar wind can spark a nice display of Northern Lights. Harald Albrigtsen took the picture on Sept. 19th from Kvalųya, Norway. There was no geomagnetic storm predicted that night, and indeed no CME struck our planet. Instead a relatively minor fluctuation in the magnetic orientation of the solar wind sparked the display.

NOAA forecasters estimate a 30% chance of polar geomagnetic storms on Sept 21st, and the probability of Arctic auroras is probably even higher than that.

-Sky watchers in parts of California are finding that, suddenly, they can view sunspots without a solar telescope. Smoke from the epic King Fire is providing a natural filter. David Wheat photographed the fiery sunset from Tuolumne CA. "Notice the 3 sunspots on the upper left of the solar disk " points out Wheat.

The fire, which began a week ago in a canyon east of Sacramento, has ballooned in size to 80,000 acres, larger than the city of Portland. Dense smoke has grounded planes and choked the air for hundreds of miles around the blaze--including a Sierra peak where the headquarters of Spaceweather.com is located. Because the fire is only 10% contained, fiery sunsets will likely continue for days to come.

Astro Picture of the Day:
September 21, 2014

Source:
How would Saturn look if its ring plane pointed right at the Sun? Before August 2009, nobody knew. Every 15 years, as seen from Earth, Saturn's rings point toward the Earth and appear to disappear. The disappearing rings are no longer a mystery -- Saturn's rings are known to be so thin and the Earth is so near the Sun that when the rings point toward the Sun, they also point nearly edge-on at the Earth. Fortunately, in this third millennium, humanity is advanced enough to have a spacecraft that can see the rings during equinox from the side. In August 2009, that Saturn-orbiting spacecraft, Cassini, was able to snap a series of unprecedented pictures of Saturn's rings during equinox. A digital composite of 75 such images is shown above. The rings appear unusually dark, and a very thin ring shadow line can be made out on Saturn's cloud-tops. Objects sticking out of the ring plane are brightly illuminated and cast long shadows. Inspection of these images is helping humanity to understand the specific sizes of Saturn's ring particles and the general dynamics of orbital motion. This week, Earth undergoes an equinox.

[Bluearrowll]

Re: Terry's Astronomy Thread.

Daily Suspicious0bserver's Weather Post:
September 22, 2014

What's in the sky tonight?
September 22, 2014

-NOAA forecasters estimate a 30% chance of polar geomagnetic storms on Sept. 23-24 when a co-rotating interaction region (CIR) is expected to hit Earth's magnetic field. CIRs are transition zones between fast- and slow-moving solar wind streams. Solar wind plasma piles up in these regions, producing density gradients and shock waves that do a good job of sparking auroras.

-The northern autumnal equinox is less than a day away. That's good news for sky watchers because, for reasons researchers do not fully understand, auroras love equinoxes. At this time of year even gentle gusts of solar wind can spark a nice display of Northern Lights. Igor Matveev took the picture on Sept. 19th from Monchegorsk, Russia. There was no geomagnetic storm predicted that night--and no meteor shower. Yet Matveev saw both. "What luck!" he says. "I caught the entire meteor streaking beneath the auroras."

No CME was required to spark the auroras. Instead, a relatively minor fluctuation in the magnetism of the solar wind caused the display. Tomorrow's CIR (co-rotating interaction region), explained above, could be even more effective.

Astro Picture of the Day:
September 22, 2014

Source:
Earth is at equinox. Over the next 24 hours, day and night have nearly equal duration all over planet Earth. Technically, equinox transpires at 2:29 am Universal Time tomorrow, but this occurs today in North and South America. This September equinox signal that winter is approaching in the northern hemisphere, and summer is approaching in the south. At equinox, the dividing line between the sunlit half of Earth and the nighttime half of Earth temporarily passes through Earth's north and south spin poles. This dividing line is shown in clear detail in the featured video, taken by the Russian meteorological satellite Elektro-L during last year's September equinox. The Elektro-L satellite is in geostationary orbit over one spot on Earth's equator and always points directly toward the Earth. The featured video shows a time lapse for an entire day surrounding the equinox, with a new image taken every 30 minutes. Cloud motions are visible as well as the reflection of the Sun are visible as the equinox day progressed. The next Earth equinox is scheduled for March.

[Bluearrowll]

Re: Terry's Astronomy Thread.

Daily Suspicious0bserver's Weather Post:
September 23, 2014

What's in the sky tonight?
September 23, 2014

-Solar activity is low. However, new sunspot AR2172 threatens to break the quiet. Karzaman Ahmad photographed the behemoth active region on Sept. 22nd from the Langkawi National Observatory in Maylasia. The sunspot's primary dark cores are nearly as wide as Earth, and the entire group stretches more than 80,000 km from end to end. These dimensions make AR2172 an easy target for small solar telescopes. "I took the picture using an 11-inch telescope," says Ahmad.

Yesterday, for a while, the sunspot's magnetic field displayed an unstable mixture of polarities that harbored energy for strong explosions. Now the threat has subsided. As the situation shifts back and forth, NOAA forcasters estimate a 30% chance of M-class flares and a 5% chance of X-flares on Sept. 23rd.

-Today, Sept. 23rd at 0229 UT, the sun crossed the celestial equator heading south. The crossing marks the beginning of fall in the northern hemisphere--a.k.a. the autumnal equinox. Equinox means equal night. With the sun near the celestial equator, we experience equal amounts of daylight and darkness, 12 hours of each. Good news for sky watchers: It's also the beginning of aurora season.

Astro Picture of the Day:
September 23, 2014

Source:
That's no sunset. And that thin red line just above it -- that's not a sun pillar. The red glow on the horizon originates from a volcanic eruption, and the red line is the eruption's reflection from fluttering atmospheric ice crystals. This unusual volcanic light pillar was captured over Iceland earlier this month. The featured scene looks north from Jökulsįrlón toward the erupting volcano Bįršarbunga in the Holuhraun lava field. Even the foreground sky is picturesque, with textured grey clouds in the lower atmosphere, shimmering green aurora in the upper atmosphere, and bright stars far in the distance. Although the last eruption from Holuhraun was in 1797, the present volcanic activity continues.

[Bluearrowll]

Re: Terry's Astronomy Thread.

Daily Suspicious0bserver's Weather Post:
September 24, 2014

What's in the sky tonight?
September 24, 2014

-Today, the interplanetary magnetic field (IMF) near Earth is tilting south, not much, but enough to open a crack in Earth's magnetosphere. Solar wind is pouring through the opening to fuel beautiful polar auroras. NOAA forecasters estimate a 40% chance that a full-fledged geomagnetic storm could develop in the next 24 hours.

-Northern autumn began with a bang, albeit only a medium-sized one. Big sunspot AR2172 erupted on Sept. 23rd at 2316 UT, producing an impulsive M2-class solar flare. NASA's Solar Dynamics Observatory captured the extreme ultraviolet flash.

The explosion might have hurled a CME toward Earth, but SOHO and STEREO coronagraph data are not yet available to confirm this possibility. Stay tuned for updates in the hours ahead.

Meanwhile, more flares are in the offing. AR2172 continues to grow and it has a 'beta-gamma' magnetic field that harbors energy for strong explosions. NOAA forcasters estimate a 30% chance of M-class flares and a 5% chance of X-flares on Sept. 24th.

Astro Picture of the Day:
September 24, 2014

Source:
The large majestic Lagoon Nebula is home for many young stars and hot gas. Spanning 100 light years across while lying only about 5000 light years distant, the Lagoon Nebula is so big and bright that it can be seen without a telescope toward the constellation of Sagittarius. Many bright stars are visible from NGC 6530, an open cluster that formed in the nebula only several million years ago. The greater nebula, also known as M8 and NGC 6523, is named "Lagoon" for the band of dust seen to the left of the open cluster's center. A bright knot of gas and dust in the nebula's center is known as the Hourglass Nebula. The featured picture is a newly processed panorama of M8, capturing five times the diameter of the Moon. Star formation continues in the Lagoon Nebula as witnessed by the many globules that exist there.

[Bluearrowll]

Re: Terry's Astronomy Thread.

Daily Suspicious0bserver's Weather Post:
September 25, 2014

What's in the sky tonight?
September 25, 2014

-A CME launched into space by the M2-class flare of Sept 23rd will not hit Earth, according to NOAA analysts. Forecast models predict that it will sail wide of our planet. More CMEs may be in the offing, however. The source of the Sept. 23rd explosion, big sunspot AR2172, has an unstable magnetic field that is likely to erupt again. Because the sun's rotation is turning the sunspot toward Earth, future CMEs will probably be geoeffective.

-How do you know it's autumn in Iceland? It's when the icebergs turn green. Last night, Steve Lansdell photographed the phenomenon from the Jokulsaron Ice Lagoon. "We've seen auroras 4 nights in a row, but last night was really spectacular," says Lansdell. "The green lit up the icebergs in a wonderful display that thrilled my friends."

These are equinox auroras, appearing less than 48 hours after the onset of northern autumn. For reasons researchers don't fully understand, auroras love equinoxes. At this time of year even a gentle gust of solar wind can spark a beautiful display. Mindful of the season, NOAA forecasters estimate a 50% chance of more polar geomagnetic storms--and more green ice--in the next 24 hours.

Astro Picture of the Day:
September 25, 2014

Source:
The large stellar association cataloged as NGC 206 is nestled within the dusty arms of the neighboring Andromeda galaxy. Also known as M31, the spiral galaxy is a mere 2.5 million light-years away. NGC 206 is near top center in this gorgeous close-up of the southwestern extent of Andromeda's disk, a remarkable composite of data from space and ground-based observatories. The bright, blue stars of NGC 206 indicate its youth. In fact, its youngest massive stars are less than 10 million years old. Much larger than the open or galactic clusters of young stars in the disk of our Milky Way galaxy, NGC 206 spans about 4,000 light-years. That's comparable in size to the giant stellar nurseries NGC 604 in nearby spiral M33 and the Tarantula Nebula, in the Large Magellanic Cloud. Star forming sites within Andromeda are revealed by the telltale reddish emission from clouds of ionized hydrogen gas.

[Bluearrowll]

Re: Terry's Astronomy Thread.

Daily Suspicious0bserver's Weather Post:
September 26, 2014

What's in the sky tonight?
September 26, 2014

-New sunspot AR2175 didn't exist one day ago. Now it stretches more than 100,000 km across the face of the sun with a primary dark core larger than Earth. The fast-growing region has a 'beta-gamma' magnetic field that harbors energy for M-class solar flares.

-As early as 8 or 9 p.m. now look for Fomalhaut, the lonely 1st-magnitude Autumn Star, twinkling on its way up from the southeast horizon. It will be highest due south around 11 or midnight (depending on your location).

-The waxing crescent Moon works its way eastward above the star-and-planet display low in the southwestern twilight. (These scenes are plotted for the middle of North America.)

Astro Picture of the Day:
September 26, 2014

Source:
Launched on November 18, 2013, the MAVEN (Mars Atmosphere and Volatile EvolutioN) spacecraft completed its interplanetary voyage September 21, captured into a wide, elliptical orbit around Mars. MAVEN's imaging ultraviolet spectrograph has already begun its planned exploration of the Red Planet's upper atmosphere, acquiring this image data from an altitude of 36,500 kilometers. In false color, the three ultraviolet wavelength bands show light reflected from atomic hydrogen (in blue), atomic oxygen (in green) and the planet's surface (in red). Low mass atomic hydrogen is seen to extend thousands of kilometers into space, with the cloud of more massive oxygen atoms held closer by Mars' gravity. Both are by products of the breakdown of water and carbon dioxide in Mars' atmosphere and the MAVEN data can be used to determine the rate of water loss over time. In fact, MAVEN is the first mission dedicated to exploring Mars' tenuous upper atmosphere, ionosphere and interactions with the Sun and solar wind. But the most recent addition to the fleet of spacecraft from planet Earth now in martian orbit is MOM.

[Bluearrowll]

Re: Terry's Astronomy Thread.

Daily Suspicious0bserver's Weather Post:
September 27, 2014

What's in the sky tonight?
September 27, 2014

-Fast-growing sunspot AR2175 has developed a 'beta-gamma-delta' magnetic field that harbors energy for significant eruptions. As a result, NOAA forecasters have upped the daily odds of M-class flares to 65% and X-flares to 10%. Stay tuned for weekend fireworks.

-During the early hours of Sept. 26th, something exploded behind the southeastern edge of the solar disk. NASA's Solar Dynamics Observatory photographed a massive plume of debris rising over the sun's limb.

As the inset shows, the plasma-plume was big enough to swallow dozens of planets Earth. In this case, however, Earth was not in the line of fire. The ejecta will completely miss our planet.

X-rays from the eruption registered C8 on the Richter Scale of Solar Flares. The actual intensity must have been much higher, though, because the flare was eclipsed by the edge of the sun. The underlying active region might be potent.

In a few days, the blast site will emerge into view as the sun's rotation turns it toward Earth. Then we will be able to evaluate its potential for future eruptions, increasingly geoeffective as the sun slowly spins on its axis.

Astro Picture of the Day:
September 27, 2014

Source:
Taken from an Atlantic beach, Cape Canaveral, planet Earth, four identically framed digital images are combined in this night skyscape. Slightly shifted short star trails dot the sky, but the exposure times were adjusted to follow the flight of a Falcon 9 rocket. The September 21 launch delivered a Dragon X capsule filled with supplies to the International Space Station. Above the bright flare seen just after launch, the rocket's first stage firing trails upward from the left. After separation, the second stage burn begins near center with the vehicle climbing toward low Earth orbit. At the horizon, the flare near center records the re-ignition and controlled descent of the Falcon 9's first stage to a soft splashdown off the coast.

[Bluearrowll]

Re: Terry's Astronomy Thread.

Daily Suspicious0bserver's Weather Post:
September 28, 2014

What's in the sky tonight?
September 28, 2014

-Weekend fireworks were predicted, and the sun complied. On Sunday, Sept. 28th (0258 UT), the magnetic canopy of sunspot AR2173 erupted, producing an M5-class solar flare. The sun was high overhead in Australia when Matt Wastell of Brisbane photographed the explosion. Extreme UV radiation from the flare ionized the top of Earth's atmosphere, disturbing the normal propagation of radio transmissions around our planet. In particular, there was a limited blackout of HF radio communications and a probable loss of shortwave radio contact in daylit areas for some tens of minutes.

At the moment, we do not know if this explosion hurled a coronal mass ejection (CME) toward Earth. Based on the impulsiveness (brevity) of the flare, we think not. A final answer awaits coronagraph data from the SOHO and STEREO spacecraft.

Wastell's picture, which he took using a solar telescope tuned to the red glow of solar hydrogen, shows more than a half-dozen dark magnetic filaments winding across the face of the sun. Like sunspots, these filaments pose a threat for flares. When a magnetic filament collapses it can hit the stellar surface and explode, causing a type of "spotless" explosion called a Hyder flare.

Taking into account all of the sunspots as well as the filaments, NOAA forecasters estimate a 65% chance of M-class flares and a 10% chance of X-flares in the next 24 hours.

Astro Picture of the Day:
September 28, 2014

Source:
What's happening at the center of active galaxy 3C 75? The two bright sources at the center of this composite x-ray (blue)/ radio (pink) image are co-orbiting supermassive black holes powering the giant radio source 3C 75. Surrounded by multimillion degree x-ray emitting gas, and blasting out jets of relativistic particles the supermassive black holes are separated by 25,000 light-years. At the cores of two merging galaxies in the Abell 400 galaxy cluster they are some 300 million light-years away. Astronomers conclude that these two supermassive black holes are bound together by gravity in a binary system in part because the jets' consistent swept back appearance is most likely due to their common motion as they speed through the hot cluster gas at 1200 kilometers per second. Such spectacular cosmic mergers are thought to be common in crowded galaxy cluster environments in the distant universe. In their final stages the mergers are expected to be intense sources of gravitational waves.