2014 SPACEWEATHER PAGES
SEPTEMBER, OCTOBER, NOVEMBER, DECEMBER
PAST SPACEWEATHER PAGES
speed: 457.7 km/sec
density: 4.2 protons/cm3
ARCTIC AURORAS: After a long, long summer day, Arctic skies are darkening again, and in the sunset observers are seeing rays of green in the twilight blue. Frank Olsen of Sortland, Norway, took this picture at sunset on Aug. 31st:
"I went out last night to catch the sunset--but mostly the auroras," says Olsen. "Even before it was dark, the Northern Lights made an appearance."
More lights are in the offing. NOAA forecasters estimate a 20% of polar geomagnetic storms during the next 24 hours. The odds of Arctic auroras are higher, however, because it doesn't take a full-fledged storm to turn the twilight green at polar latitudes. Now is a good time to book a tour. Aurora alerts: text, voice
Realtime Aurora Photo Gallery
speed: 410.0 km/sec
density: 6.9 protons/cm3
MARS COMET PASSES STAR CLUSTER: Comet Siding Spring (C/2013 A1) is hurtling toward Mars for a near miss on Oct. 19, 2014. En route, a different near miss occured. On Aug. 28, the "Mars Comet" pass almost directly in front of globular star cluster NGC 362:
"I took the picture shortly after minimum separation between the two," says astrophotographer Damian Peach of Selsey, UK.
Less than two months from now the comet will reach Mars. Although the comet's nucleus will not strike the planet, gas and dust spewing out of the comet's core will likely interact with the Martian atmosphere. There could be a meteor shower, auroras, and other effects that no one can predict. NASA's fleet of Mars spacecraft and rovers will record whatever happens.
Amateur astronomers can monitor the comet's approach to Mars in the months ahead. Right now, Siding Spring is gliding through the southern constellation Tucana glowing about as brightly as a 11th magntitude star. Mid-sized telescopes such asthe Comet Hunter equipped with CCD cameras should have no trouble picking it up. [light curve] [ephemeris] [3D orbit]
Realtime Comet Photo Gallery
26 FIREBALLS REPORTED
speed: 414.9 km/sec
density: 4.9 protons/cm3
COMET LANDING SITE SLIDESHOW: In mid-November, ESA's Rosetta spacecraft will make history by dropping a probe onto the surface of a comet. Bristling with 10 sensors including a camera, the Philae lander will touchdown somewhere on the rugged double-lobed core of comet 67P/Churyumov-Gerasimenko. But where? A new slideshow previews 5 candidate landing sites.
AURORAS EXPLODE THROUGH ARCTIC TWILIGHT: "After a long summer without stars, the Northern Lights have finally returned," reports Fredrik Broms of Tromsø, Norway (70 deg N latitude). "Last night's display was so strong that, although constellations such as Cassiopeia are still only to be made out very faintly on the blue night sky, the auroras shimmered and danced in an explosion of colors!" This is what he saw almost directly overhead around local midnight on August 28th:
25 FIREBALLS REPORTED
speed: 359.0 km/sec
density: 7.5 protons/cm3
GEOMAGNETIC ACTIVITY: Earth's magnetic field is still reverberating from a pair of CME strikes on August 27th. Although neither impact was particularly strong, the internal magnetic structure of the two solar storm clouds was just right for auroras. Last night, Alan Dyer photographed the display over the Grasslands National Park in Saskatchewan, Canada. Click to view a complete panorama:
"I shot this at the old pioneer Larson Ranch site in the Frenchman River valley just as the magnetic storm of Aug 27/28 hit its peak, covering much of the northern sky and lighting the ground and ranch buildings green," says Dyer. "The Larsons ran their ranch from the 1920s until 1985 when theirs became first land to be bought for the new Grasslands National Park. This is a stitch of 8 segments, each shot with the 15mm full-frame fish-eye lens at f/3.2 and Canon 6D at ISO 2500 for 1 minute each."
The CMEs that instigated the display were launched toward Earth on Aug. 22nd. As NOAA analysts predicted, the solar wind speed did not change much when the slow-moving CMEs arrived. However, the storm clouds were still effective because they contained a south-pointing magnetic field that opened a crack in Earth's magnetosphere. Solar wind poured in to fuel the show.
High-latitude sky watchers, if it is dark where you live, remain alert for auroras. Solar wind conditions continue to favor geomagnetic activity as August 28th unfolds.Aurora alerts: text, voice
27 FIREBALLS REPORTED
speed: 327.8 km/sec
density: 8.4 protons/cm3
GEOMAGNETIC ACTIVITY: Earth's magnetic field is unsettled today following the arrival of a CME during the early hours of August 27th. Around the North and South Poles, high-latitude sky watchers are reporting intermittently-bright auroras, like these photographed last night by Mike Theiss on the east coast of Iceland:
"The lights were incredible," says Theiss. "They changed intensity on and off for about 3 hours." Additional reports have come from New Zealand, Canada and northern-tier US states such as Maine, Michigan, Wisconsin, Idaho, North Dakota, and Washington: photo gallery.
The CME that instigated the display was launched toward Earth on Aug. 22nd. As NOAA analysts predicted, the solar wind speed did not change much when the slow-moving CME arrived. However, the storm cloud was still effective because it contained a south-pointing magnetic field that opened a crack in Earth's magnetosphere. Solar wind is poured in to fuel the show.
High-latitude sky watchers, if it is dark where you live, be alert for auroras. Solar wind conditions continue to favor geomagnetic activity as August 27th unfolds.Aurora alerts: text, voice
COMET CANDIDATE LANDING SITES SELECTED: Working over the weekend, Rosetta mission planners and scientists narrowed a list of 10 candidate landing sites to only 5. They are circled in this image of the core of 67P/Churyumov-Gerasimenko:
In mid-November, Rosetta's Philae lander will attempt to touch down in one of these locations--the first time humankind has ever landed a probe on the core of a comet.
The candidate sites are distributed as follows: three (I, B and J) on the comet's smaller lobe and two (A and C) on the larger. The comet's canyon-like neck has been excluded. All of the candidate landing sites provide at least six hours of daylight per comet rotation and offer some flat terrain. According to the ESA, every site has the potential for unique scientific discoveries by the lander's 10 instruments.
A full discussion of each site may be found in this ESA press release. By September 14th, the five candidates will have been assessed and ranked, leading to the selection of a primary landing site, for which a fully detailed strategy for the landing operations will be developed, along with a backup. Stay tuned for updates as the selection process unfolds.
Realtime Comet Photo Gallery
37 FIREBALLS REPORTED
speed: 254.8 km/sec
density: 3.4 protons/cm3
speed: 254.8 km/sec
density: 3.4 protons/cm3
MINOR STORM WARNING: A CME is heading for Earth. The relatively slow-moving storm cloud left the sun on Aug. 22nd and looks like it will take 4 days to cross the sun-Earth divide. NOAA forecasters estimate a 15% to 20% chance of polar geomagetic storms on Aug. 26-27 when the CME arrives. Aurora alerts: text,voice
7 FIREBALLS REPORTED
speed: 280.5 km/sec
density: 5.8 protons/cm3
M" FOR MAGNIFICENT: In the vocabulary of space weather, an "M-flare" is a medium-sized explosion. Yesterday it had a different meaning: magnificent. On August 24th at 12:17 UT, NASA's Solar Dynamics Observatory recorded this M5.6-category explosion near the eastern limb of the sun:
The source of the blast was sunspot AR2151. As the movie shows, an instability in the suspot's magnetic canopy hurled a dense plume of plasma into space. If that plasma cloud were to hit Earth, the likely result would be strong geomagnetic storms. However, because of the sunspot's location near the edge of the solar disk, Earth was not in the line of fire.
Even so, the flare did produce some Earth effects. A pulse of extreme UV radiation from the explosion partially ionized our planet's upper atmosphere, resulting in a Sudden Ionospheric Disturbance (SID). Waves of ionization altered the normal propagation of VLF (very low frequency) radio transmissions over the the dayside of Earth, an effect recorded at the Polarlightcenter in Lofoten, Norway: data.
Sunspot AR2151 will turn toward Earth in the days ahead, which means subsequent explosions could be more geoeffective. Follow the action @spaceweatherman
An explosion in the magnetic canopy of emerging sunspot AR2151 hurled a dense and twised plume of plasma into space. The Solar and Heliospheric Observatory (SOHO) recorded a bright coronal mass ejection emerging from the blast site:movie. If this CME were to ht Earth, the likely result would be strong geomagnetic storms. However, because of the sunspot's location near the sun's eastern horizon, Earth was not in the line of fire.
Nevertheless, the flare did produce some Earth effects. A pulse of extreme UV radiation partially ionized our planet's upper atmosphere. This "Sudden Ionospheric Disturbance" (SID) altered the normal propagation of VLF (very low frequency) radio transmissions over the the dayside of Earth, an effect recorded at the Polarlightcenter in Lofoten, Norway: data.
This sunspot will turn toward Earth in the days ahead, which means subsequent explosions could be more geoeffective. Stay tuned for updates. Solar flare alerts:text, voice
12 FIREBALLS REPORTED
speed: 321.3 km/sec
density: 3.5 protons/cm3
CELESTIAL TRIANGLE: The three brightest objects in the night sky, Venus, Jupiter and the Moon, converged this morning to form a bright triangle visible around the world. Kenneth Parsons sends this picture from Corpus Christi, Texas:
"I shot this at 6:10 AM on an absolutely clear morning with only a hint of breeze to mar the reflection of the Moon in the water," says Parsons.
Did you miss the show? Another "celestial triangle" is in the offing. This weekend the Moon will pass the sun en route to the evening sky. On August 31st it will join Mars and Saturn to form a new triangle in the constellation Libra. The new triangle won't be quite as luminous, because Mars and Saturn are not as bright as Venus and Jupiter, but the Moon-Mars-Saturn formation will be more compact and just as beautiful. Mark your calendar for the end of the month.
Realtime Conjunction Photo Gallery
19 FIREBALLS REPORTED
speed: 344.7 km/sec
density: 3.6 protons/cm3
COMET LANDING SITE SELECTION: Europe's Rosetta probe has been at Comet 67P/Churyumov-Gerasimenko for two weeks, taking close-up pictures and making measurements of the comet's strange landscape. According to ESA, researchers now have the data they need to start picking a landing site. This weekend, mission planners will meet to consider 10 candidate locations, with the goal of narrowing the list to 5 by Monday. Stay tuned for results!
SOLAR ACTIVITY PICKS UP: A new sunspot emerging over the sun's NE limb is bringing an uptick in solar activity. AR2149 announced itself on August 21st with an impulsive M3-class solar flare. NASA's Solar Dynamics Observatory recorded the explosion's extreme ultraviolet flash:
UV radiation from the flare partially ionized the upper layers of Earth's atmosphere. This "Sudden Ionospheric Disturbance" altered the normal propagation of VLF (very low frequency) radio transmissions over the northern hemisphere, shown here in a recording from the Polarlightcenter in Lofoten, Norway. The disturbance has since subsided.
Because AR2149 is near the sun's eastern horizon, our view of the region is foreshortened. Evaluating the structure of its magnetic field is therefore tricky. As the sunspot turns toward Earth in the days ahead, we will get a better idea of its flare-producing potential. For now, NOAA forecasters are estimating a 25% chance of M-flares in the next 24 hours. Solar flare alerts: text, voice
WEAK IMPACT? MAGNIFICENT AURORAS: Visually, the CME that struck Earth's magnetic field on August 19th was dim and unimpressive. The auroras it produced were magnificent. "For the first time in my life, I saw the Northern Lights," says Tadas Janušonis who sends this photo from Vabalninkas, Lithuania:
"It is a very rare phenomenon here in Lithuania," he says, "but the August 19th impact was strong enough to [produce] them."
Actually, the impact was weak. A CME like this one hits with a mechanical pressure of no more than 1 or 2 nanoPascals. That's 1 or 2 billionths of a Pascal - softer than a baby's breath. The reason it was so effective had more to do with its inner magnetic structure. This CME contained a region of south-pointing magnetism that partially canceled Earth's north-pointing magnetic field, opening a crack in the magnetosphere. Solar wind poured and fueled the display.
The most famous photo of the storm, so far, was taken by astronaut Reid Wiseman onboard the International Space Station. "Never in my wildest dreams did I imagine this, " he tweeted. "Unbelievable." Yet many more photos prove that it really did happen! Aurora alerts: text, voice
Realtime Aurora Photo Gallery
20 FIREBALLS REPORTED
speed: 327.2 km/sec
density: 1.0 protons/cm3
GEOMAGNETIC STORM, AURORAS SEEN FROM SPACE: A moderate (G2-class) geomagnetic storm that erupted following a CME strike on August 19th issubsiding now. At its peak, the storm sparked auroras around both poles visible from the ground and from space. Astronaut Reid Wiseman took this picture from the window of the International Space Station:
"Never in my wildest dreams did I imagine this," tweeted Wiseman (@astro_reid). "Unbelievable."
Around the Arctic Circle where the midnight sun has overwhelmed auroras since Spring, observers caught their first glimpse of Northern Lights in months "At one point a massive corona unfolded just over my head!" reports Alexander Kuznetsov from the Finnish Lapland. "It was a great season opener," added Pekka Hyytinen of Tampere, Finland. "I also caught a lightning strike in one of my photos."
Solar wind conditions are unsettled but calming as Earth passes through the wake of the CME. NOAA forecasters estimate a waning 30% to 15% chance of more geomagnetic storms during the next 24 hours. Aurora alerts: text, voice
Realtime Aurora Photo Gallery
46 FIREBALLS REPORTED
speed: 326.6 km/sec
density: 2.5 protons/cm3
MORNING SHOW CONTINUES: Light pollution? No problem. The morning conjunction of Venus and Jupiter is bright enough to see through the worst urban glare. Jeff Dai sends this picture from metropolitan Chongqing, China:
"I woke up at 5 AM to enjoy this celestial dawn above the cityscape," says Dai. "It was gorgeous."
Dai took the picture on August 20th, two days after Venus and Jupiter were barely 0.2o apart. Many observers have stopped looking now that the planets are separating, but as Dai's photo shows, they are still a beautiful pair. So set your alarm for dawn: the morning show continues. A date of special interest is August 23rd when the crescent Moon joins the planets to form a must-see celestial triangle.A video from NASA previews the meeting.
Realtime Conjunction Photo Gallery
speed: 411.7 km/sec
density: 8.2 protons/cm3
WEAK IMPACT: A CME hit Earth's magnetic field on August 19th at approximately 06:30 UT. The weak impact did not spark a strong geomagnetic storm nor any reports (so far) of visible auroras. NOAA forecasters say there is still a 30% chance of minor geomagnetic storms as Earth passes through the CME's wake. Update:Faint auroras have been reported over Alaska.
"It was a beautiful celestial dawn," says Nikodem, "definitely worth waking up for."
Following their 0.2o near-miss on Monday, August 18th, Venus and Jupiter are separating, but not too quickly. They'll remain in the same patch of sunrise sky for the rest of the week. A date of special interest is August 23rd when the crescent Moon joins the planets to form a must-see celestial triangle. A video from NASA previews the meeting.
HE SURPRISING POTENCY OF "WEAK" FLARES: For the past month, the sun has been mostly quiet with only a smattering of C- and B-class solar flares. As flares go, these are puny. In fact, when the sun is crackling with flares no stronger than B-class, we often say that "solar activity is very low."
But is it, really? A B-class solar flare packs a bigger punch than is generally supposed. Consider this specimen photgraphed by Harald Paleske of Weißenfels/ OT Langendorf, Germany, on August 17th:
"This was a B8-class flare in sunspot AR2144," says Paleske. "Despite poor seeing, I was able to capture a high-resolution view of the explosion using my 225mm Unigraph solartelescope."
The violence frozen in these snapshots belies the idea that this was a weak explosion. And indeed it was not. A typical B-class solar flare releases as much energy as 100 million WWII atomic bombs. Only on the sun, which is itself a 1027ton self-contained nuclear explosion, would such a blast be considered puny.
So the next time you hear that the forecast calls for "low solar activity," remember ... everything is relative. Today's forecast, by the way, calls for low solar activity with only a 10% chance of M-class solar flares.
speed: 293.1 km/sec
density: 4.8 protons/cm3
CHANCE OF MINOR STORMS: NOAA forecasters estimate a 30% chance of polar geomagnetic storms on August 18th when a faint CME is expected to strike Earth's magnetic field head-on. This is not a major event. Nevertheless, high-latitude sky watchers should be alert for auroras when the CME arrives. Follow the action@spaceweatherman.
MORNING PLANETS: Did you see that? This morning Venus and Jupiter converged in the pre-dawn sky for a spectacular conjunction. At closest aproach they were barely 0.2o apart. Richard S. Wright Jr. sends this picture from Lake Mary, Florida:
"This was worth setting my alarm for this morning," says Wright. "Jupiter and Venus were so close together, and rapidly rising as the sky brightened. I grabbed my tripod and caught them under my neighbors trees."
The planets are separating now, but not too quickly. They will still be a beautiful pair for the rest of the week. A date of special interest is August 23rd when the crescent Moon joins the planets to form a bright celestial triangle in the eastern pre-dawn sky.
Observing tips: Go outside 60 minutes before sunrise and look east-northeast. No telescope is required. Jupiter and Venus are bright enough to see with the naked eye even from light polluted cities. Try following the bright pair after the dawn sky begins to brighten. A tight conjunction of Venus and Jupiter framed by twilight blue is a great way to start the day. For more information, see this video from NASA.
Realtime Conjunction Photo Gallery
speed: 294.4 km/sec
density: 3.1 protons/cm3'
speed: 270.3 km/sec
density: 1.5 protons/cm3
MORNING PLANETS: Set your alarm for dawn! Venus and Jupiter are converging for a spectacular conjunction in the early morning sky. Closest approach: August 18th. A video from NASA previews the encounter
THE LANDSCAPE OF A COMET: On August 6th, Europe's Rosetta spacecraft rendezvoused with Comet 67P/Churyumov-Gerasimenko and began to fly alongside it. Seven days later, mission scientists released this spectacular view of the comet's double-lobed core:
A closer look reveals many interesting features: While the comet's head (in the top half of the image) is scored with parallel linear features, the neck is peppered with boulders resting on a smooth underlying terrain. In comparison, the comet's body (lower half of the image) is jagged and dimpled by crater-like depressions.
Now imagine this magnificent landscape ruptured by dozens of geysers spewing dust and gas into space. Future pictures may show exactly that. Rosetta will follow this comet for more than a year as it approaches the sun. In 2015, if not sooner, solar heating will activate the comet's icy core, creating a riot of activity the likes of which no spacecraft has ever seen before. Stay tuned for that.
Realtime Comet Photo Gallery
54 FIREBALLS REPORTED
speed: 327.5 km/sec
density: 1.8 protons/cm3
EARTH-DIRECTED ERUPTION: A magnetic filament snaking down the middle of the solar disk erupted on Aug. 15th at approximately 1700 UT. Quick-look data from NASA's STEREO probes suggest that the blast hurled a CME toward Earth. If so, the cloud would probably arrive on or about Aug. 18th
57 FIREBALLS REPORTED
speed: 372.3 km/sec
density: 2.3 protons/cm3
PERSEID METEOR SHOWER--PEAKING NOW: According to the International Meteor Organization, the Perseid Meteor Shower is peaking now with as many as 50 meteors per hour. These rates are sharply reduced, compared to a normal year, because of the glare from the waning supermoon. It is still, however, a significant shower. If it is dark where you live, go outside and look up. Otherwise, try listening to Perseid radar echoes on Space Weather Radio.
PERSEID METEOR SHOWER, STILL ACTIVE: Observers reporting to the International Meteor Organization say that Perseid meteor rates are still high, greater than 40 per hour on Aug. 13-14. This means Earth has not yet exited the debris stream of parent comet Swift-Tuttle. If it is dark where you live, go outside and look up. Otherwise, try listening to Perseid radar echoes on Space Weather Radio.
PERSEID FIREBALLS AND METEOR SMOKE: Before the Perseid meteor shower began, forecasters worried that people might not see it due to the glare of a supermoon. This photo illustrates why the Perseids succeeded in spite of lunar interference; the shower is rich in fireballs:
This was the brightest Perseid I saw on the night of August 12/13," says photographer Pete Lawrence. "Visually, it was a stunner!"
After the meteor exploded over Lawrence's home in Selsey, UK, a wispy trail of debris appeared where the meteor had been a split-second before. "I recorded it in the very next frame," he says.
This is "meteor smoke," a sinuous cloud of microscopic cinders tracing the path of the incinerating fireball. The particles of meteor smoke disperse in Earth's upper atmosphere and, ultimately, become the seeds of noctilucent clouds. All meteors produce such smoke, but only the brightest fireballs create a lingering trail bright enough to see with the unaided eye.
Light from the supermoon, ironically, helps us see meteor smoke, because reflected moonlight increases the visibility of smoky debris. As a result, the smoke may have been photographed more often than usual during the 2014 Perseids. Browse the realtime meteor gallery to search for additional examples.
speed: 405.2 km/sec
density: 1.3 protons/cm3
speed: 462.4 km/sec
density: 1.3 protons/cm
mars.nasa.gov/comets/sidingspring/ - Similarto Comets: Siding Spring (C/2013 A1) - Mars Exploration Program
All about comet Siding Springs' close approach to Mars on Oct. 19, 2014.
en.wikipedia.org/wiki/C/2013_A1 - Similarto C/2013 A1 - Wikipedia, the free encyclopedia
C/2013 A1 (Siding Spring) is an Oort cloud comet discovered on 3 January 2013 by Robert H. McNaught at Siding Spring Observatory using the 0.5-meter (20 ...
www.fallofathousandsuns.com/comet-siding-spring.html - Similarto Comet Siding Spring and Mars - Fall of a Thousand Suns
Discovery of Comet Siding Spring (C/2013 A1). A comet was discovered by Robert McNaught on January 3, 2013 with a 20" (0.5 m) Schimdt telescope at the ...
www.livecometdata.com/comets/c2013-a1-siding-spring/ - Similarto Comet Siding Spring (C/2013 A1) Real-Time Data and Information
Discovered in January of last year, it was quickly established that Comet Siding Spring (C/2013 A1) was going to pass 'very' close to Mars on October 19th this ...
www.universetoday.com/.../mars-bound-comet-siding-spring-sprout... - Similarto Mars-Bound Comet Siding Spring Sprouts Multiple Jets
Mar 27, 2014 ... Comet Siding Spring, on its way to a close brush with Mars on October 19, has been kicking up a storm lately. New images from Hubble Space ...
May 8, 2014 ... It may be the chance of a lifetime for planetary science. This October, acomet will brush past a planet, giving scientists a chance to study how it ...
www.space.com/25257-mars-comet-siding-spring-photos-c2013-a1.ht... - Similarto Mars-Bound Comet: Photos of Comet C/2013 A1 Siding Spring ...
Mar 27, 2014 ... See photos and images of the Mars-bound comet C/2013 A1 SidingSpring, which will buzz the Red Planet on Oct. 19, 2014.
Aug 4, 2014 ... Comet Siding Spring will sweep past Mars in October, then follow other recent comets around the sun and back into deep space. AUG. 4, 2014 ...
Jun 27, 2014 ... Graphic depiction the orbit of Siding Spring's (aka comet C/2013 A1) trajectory as it swings around the Sun in 2014. On Oct. 19, the comet will ...
PERSEID METEOR SHOWER: The annual Perseid meteor shower peaks tonight, Aug. 12-13, as Earth passes through a stream of debris from Comet Swift-Tuttle. Forecasters expect peak rates of 30 to 40 meteors per hour, less than usual because of the glare from the waning supermoon. Observing tips: To reduce the effects of moonlight, pick an observing site with clear, dry air. Also try watching the sky from the moonshadow of a tall building or other obstacle. Many Perseid fireballs will be visible in spite of the glare. [NASA chat]
Unaffected by moonlight, the Canadian Meteor Orbit Radar (CMOR) is scanning the skies above North America for echoes from disintegrating meteoroids. The latest CMOR sky map shows strong activity from the constellation Perseus (PER):
Click to view a radar map of the entire sky. The Perseids are not alone. In the southern hemisphere, a cluster of lesser radiants is also active. Foremost among them is the Southern Delta Aquarids (SDA) probably caused by debris from Comet96P/Machholz. Delta Aquarid fireballs will augment the Perseids south of the equator.
Because of the moonlight, radar may be the best way to observe tonight's shower. You can listen to meteor radar echoes in realtime on Space Weather Radio.
Realtime Meteor Photo Gallery
48 FIREBALLS REPORTED
speed: 415.6 km/sec
density: 4.6 protons/cm3
ARS COMET WORKSHOP: On Oct. 19, 2014, Comet Siding Spring will pass so close to Mars that the atmosphere of the comet might interact with the atmosphere of the Red Planet. Today, researchers are gathering at the Johns Hopkins University Applied Physics Laboratory to discuss the encounter. The meeting will be streamed live starting at 8:45 AM EDT on Aug. 11th. Members of the public are welcome to listen and ask questions on Twitter using the hashtag #MarsComet.
WEEKEND SUPERMOON: The full Moon of August 10th was as much as 14% bigger and 30% brighter than other full Moons of the year. Some say that makes it asupermoon. Others retort that it's really not as super as the media has made it out to be. Who's correct? Vesa Vauhkonen of Rautalampi, Finland, took a stab at settling the question with this side-by-side comparison:
"I compared the normal full Moon of March 2014 with the Supermoon of Aug 2014," says Vauhkonen. "In individual images, the difference in size might be difficult to see, but putting them side by side makes the difference clear. I used the same photo settings for both images, so the scaling has no errors."
Supermoons are possible because the Moon's orbit is not a circle, it is an ellipse. One side, perigee, is 50,000 km closer than the other, apogee. On August 10th the Moon became full just as it reached perigee, the point closest to Earth. This caused the Moon to appear authentically bigger and brighter than usual.
More photos of the full Moon, and the landscape of Earth bathed in super-moonlight, may be found in the realtime photo gallery:
Realtime Space Weather Photo Gallery
13 FIRBALLS REPORTED
speed: 445.0 km/sec
density: 7.1 protons/cm3
QUIET SUN: As the one-month anniversary of the "All-Quiet Event" approaches, the sun's global X-ray output is sinking again. Solar activity is very low. Only one sunspot (AR2135) poses a threat for significant flares, but it seems reluctant to erupt. Follow the action, or lack thereof, @spaceweatherman.
THE SUPERMOON RISES: Tonight's full Moon is the biggest and brightest full Moon of the year. Astronomers call it a perigee moon; the popular term is "supermoon." Stephen Mudge photographed the bright orb rising over the Mormon temple in Brisbane, Queensland, on Aug. 10th:
Supermoons are possible because the Moon's orbit is not a circle, it is an ellipse. One side, perigee, is 50,000 km closer than the other, apogee. Today the Moon becomes full just as it reaches perigee, the point closest to Earth. The perigee supermoon you see tonight is as much as 14% closer and 30% brighter than other full Moons of the year.
DOUBLE SPACESHIP FLYBY: On Fridy, August 8th, Europe's robotic cargo carrier, the "George Lemaitre," flew just 4 miles underneath the International Space Station. In Berlin, Germany, astrophotographer Thomas Becker recorded the close encounter:
"I caught the two spacecraft over the Wilhelm-Foerster-Observatory in Berlin," says Becker. "Bright moonlight completed the scenery."
Loaded with more than seven tons of fuel and supplies, the George Lemaitre (a.k.a. "ATV-5") is scheduled to dock with the ISS on Tuesday, Aug. 12th. Friday's preliminary flyby allowed mission controllers to test a suite of lasers and sensors that may be incorporated into the design of future European spacecraft.
George Lemaitre, the man, was a 20th century Belgian astronomer and physicist credited with proposing the theory of the expansion of the universe. ATV-5, the fifth in Europe's series of Automated Transfer Vehicles for shuttling supplies to the ISS, was named in his honor.
The duo wil be flying in tandem over the USA
13 FIREBALLS REPORTED
speed: 330.4 km/sec
density: 2.6 protons/cm3
RELUCTANT SUNSPOTS: Sunspot AR2135 has a 'beta-gamma' magnetic field that harbors energy for M-class solar flares. Like every other sunspot that has crossed the solar disk in the past month, however, AR2135 seems reluctant to erupt. Solar activity is low and will likely remain so for the rest of the weekend.
PERSEID METEOR UPDATE The Perseid meteor shower is underway as Earth moves into the debris stream of parent comet Swift-Tuttle. According to the International Meteor Organization, the constellation Perseus is now spitting out meteors at a rate of about 20 per hour. In a normal year, those rates would increase 4- or 5-fold as the shower reaches its peak on August 12-13. But this is no normal year. In 2014, the glare of a supermoon will interfere with Perseid visibility, capping visible meteor rates at no more than ~30 per hour.
Now for the good news: The Perseids are rich in fireballs, and many of those extra-bright meteors can be seen in spite of the lunar glare.
the meteor cut through the moonlight wih ease. In the past week, NASA's network of all-sky cameras has recorded nearly 100 Perseid fireballs over the USA, and more are in the offing. So, note to sky watchers: Don't be put off by the supermoon. A trip to the moonlit countryside on August 12-13 will be rewarded by a display of Perseids, albeit fewer than usual.
A good time to look on those nights might be during the hours after sunset when the Moon is still hanging low in the sky and the constellation Perseus is rising in the northeast. Such an arrangement can produce a special type of meteor called an earthgrazer. Earthgrazers emerge from the horizon and skim the top of the atmosphere above the observer, a bit like a stone skipping across the surface of a pond. An hour's watching might net no more than one or two of this special kind of meteor, but that's plenty. Earthgrazers are colorful and gracefully slow, a rare beauty that makes any meteor-watch worthwhile.
17 FIREBALLS REPORTED
speed: 366.5 km/sec
density: 1.6 protons/cm3
PERSEID FIREBALLS: The full Moon of August 10th is no ordinary full Moon--it's a supermoon, the biggest and brightest of 2014. This has raised concerns that bright moonlight will outshine the Perseid meteor shower, underway now as Earth moves into the debris stream of parent Comet Swift-Tuttle. So far the Perseids are holding their own. In recent nights, observers have reported dozens of Perseid fireballs cutting through the glare.
Play it again. The ghostly warbling sound you hear was a terrestrial radio signal bouncing off the ionized trail of the fireball. This method of detecting meteors is called "forward scatter radar." Ashcraft, who is an amateur radio astronomer, routinely uses this method to monitor meteor activity over his observatory not far from Santa Fe. Lately, he has been recording lots of echoes.
"My radio fireball array and all-sky camera caught this Perseid earthgrazer at 11:30 pm here in New Mexico as the constellation Perseus was coming up over the northern horizon," says Ashcraft. "It caused a dynamic dopplering forward scatter reflection in stereo on two of my radios."
"Even though there is a bright moon at the moment, there will still be some beautiful Perseids over the next few nights," he predicts.
83 FIREBALLS REPORTED
speed: 369.6 km/sec
density: 1.7 protons/cm3
speed: 456.4 km/sec
density: 0.8 protons/cm3
COMET RENDEZVOUS--TODAY! The European Space Agency's Rosetta probe has reached 67P/Churyumov-Gerasimenko and is maneuvering to go into orbit around the comet's core. This is an historic event. After Rosetta goes into orbit, it will follow the comet around the sun, observing its activity from point-blank range for more than a year. Moreover, in November, Rosetta will drop a lander onto the comet's strange surface. Today's events are being streamed live by the ESA.
After 10 years and four billion miles, the European Space Agency’sRosetta spacecraft will arrive at its destination on Wednesday for the first extended, close examination of a comet.
The last in a series of 10 thruster firings over the past few months will slow Rosetta to the pace of a person walking, about two miles per hour relative to the speed of its target, Comet 67P/Churyumov-Gerasimenko, at a distance of about 60 miles.
Photographs have already revealed a surprisingly irregular shape for the 2.5-mile-wide comet, possibly an amalgamation of two icy bodies or a result of uneven weathering during previous flybys. From a distance, the blurry blob initially looked somewhat like a rubber duck. As the details came into the focus, it now more resembles a knob of ginger flying through space.
Continuing a trend of anthropomorphizing, the Rosetta mission managers tweeted a photograph of the comet on Monday with the comment “Do you think I got #67P’s good side yesterday?”
39 FIREBALLS REPORTED
speed: 459.9 km/sec
density: 4.7 protons/cm3
PERSEID METEOR SHOWER: Meteor activity is increasing as Earth plunges deeper into the debris stream of Comet Swift-Tuttle, source of the annual Perseid meteor shower. On the night of Aug 3-4, NASA cameras recorded more than a dozen Perseid fireballs over the USA. Counts are high even though the shower's peak is still more than a week away. To see for yourself, get away from city lights and look up during the dark hours before sunrise. You can also hear the Perseids onSpace Weather Radio.
FIREBALL EXPLODES, SPRAYS COUNTRYSIDE: On Saturday night, August 2nd, NASA meteor cameras detected a fireball that exploded in a flash of light many times brighter than the Moon. It came not from the Perseid debris stream, but rather from the vicinity of the asteroid belt between Mars and Jupiter.
"The meteoroid was about 15 inches in diameter and weighed close to 100 lbs," says Bill Cooke of NASA's Meteoroid Environment Office. "Travelling 47,000 miles per hour, it broke apart in a brilliant flash of light above the Alabama town of Henagar. Our cameras continued to track a large fragment until it disappeared 18 miles above Gaylesville, located near Lake Weiss close to the Georgia state line. At last sight, the fragment was still traveling at 11,000 miles per hour. Based on the meteor's speed, final altitude, and weak doppler radar signatures, we believe that this fireball produced small meteorites on the ground somewhere between Borden Springs, AL and Lake Weiss."
The NASA Meteoroid Environment Office would like to hear from those in the area around Alabama's Lake Weiss who may have heard sonic booms or similar sounds around 10:20 PM Saturday night. Please contact Dr. Bill Cooke at email@example.com with reports.
23 FIREBALLS REPORTED
speed: 420.7 km/sec
density: 3.9 protons/cm3
METEOR ACTIVITY: Meteor activity is increasing as Earth plunges deeper into
the debris stream of Comet Swift-Tuttle, source of the annual Perseid meteor
shower. Last night alone, NASA cameras recorded more than a dozen Perseid
fireballs along with one sporadic bolide (exploding meteor) that might have
dropped pieces of itself over the southeastern USA. Visit
http://spaceweather.com for video and observing tips.
CHANCE OF FLARES: Sunspot AR2130 is directly facing Earth and it has a complex 'delta-class' magnetic field that harbors energy for strong flares. X-flare alerts are available from http://spaceweathertext.com (text) and http://spaceweatherphone.com (voice).
PLANETS CROSSING AT NOON This weekend, Jupiter and Mercury are in conjunction. Don't bother looking because the meeting takes place in the noontime sky. What human eyes cannot see, however, spacecraft can. Using an opaque disk to block the glare of the sun, the Solar and Heliospheric Observatory (SOHO) is monitoring the encounter:
At closest approach on August 2nd, the two bright planets were less than 1o apart. If such an alignment occured at night, it would surely be headline news. At noon, its just spaceweather news. Join SOHO for a ringside seat.
18 FIREBALLS REPORTED
speed: 392.3 km/sec
density: 3.3 protons/cm3
MINOR STORM WARNING, CANCELLED: A CME expected to sideswipe Earth's magnetic field on August 2nd has not arrived. The tardy cloud is either off target or moving more slowly than forecasters thought, or both. The chance of a geomagnetic storm this weekend is waning
sunspot AR2132 has a 'beta-gamma-delta' magnetic field that harbors energy for X-class solar flares. Credit: SDO/HM
18 FIREBALLS REPORTED
speed: 412.6 km/sec
density: 2.6 protons/cm3
MINOR STORM WARNING: A CME is heading for Earth. The cloud was hurled into space on July 30th when a magnetic filament on the sun erupted, and it appears to be on course to sideswipe Earth's magnetic field. NOAA forecasters estimate a 30% chance of polar geomagnetic storms on Aug. 2nd when the CME arrives.Aurora alerts: text, voice
AMAZING NEW PHOTO OF THE ROSETTA COMET: Today, the ESA released a new image of Comet 67P/Churyumov-Gerasimenko as seen from the Rosetta probe only 1000 km away. It shows the rough surface of the comet's double nucleus in amazing detail:
The photo was taken on Aug. 1st at 02:48 UTC by Rosetta's OSIRIS Narrow Angle Camera. The dark spot near image-center is an artifact from the onboard CCD.
This new view heightens anticipation for August 6th when Rosetta reaches the comet and goes into orbit around it. Then we will see the strange double-core from point-blank range, and researchers can start to pick touchdown sites for Philae, a lander that will descend to the comet's surface in November.
Only 4 days to rendezvous! Follow the action @ESA_Rosetta.
Realtime Comet Photo Gallery
RADIO BURSTS FROM THE SUN: Yesterday, the loudspeakers of shortwave radios erupted with static. The source of the noise was the sun. "I have been picking up solar bursts on my RadioJove receiver at 20.1 MHz," reports Kevin Palivec of Hawley, Texas. This chart recording displays 10 minutes of activity on August 1st:
The bursts were triggered by an M2-class explosion in the magnetic canopy of sunspot AR2127. The explosion sent shock waves rippling through the sun's atmosphere. Those shock waves, in turn, excited plasma instabilities that emit static-y radio waves. Becase there are a whole variety of plasma instabilites, there is a corresponding variety of radio burst types. Palivec recorded a mix of two: Type II and Type IV.
More solar radio bursts could be in the offing as sunspot AR2127 and nearby sunspot AR2130 both crackle with M-class solar flares. Visit NASA's RadioJove website to find out how to build your own receiver--and listen up.
On August 1st, two M-class flares fired off from sunspot regions
2130 and 2127, both of which were located at the Sun's central
meridian producing direct hits to Earth.
Within 24 to 48 hours of these solar storms, four tropical storms;
Genevieve, Bertha, Halong, Iselle - were either produced or
elevated. Within an additional 24 hours, the NOAA Tsunami Warning
Center a 7.2 magnitude earthquake hit near Lorengau, Papua New
Guinea at 00:22:03 UTC, August 3rd 2014. No reports of damage or
injury at this time.
On August 1st, two M-class flares fired off from sunspot regions 2130 and 2127, both of which were located at the Sun's central meridian producing direct hits to Earth.
Within 24 to 48 hours of these solar storms, four tropical storms; Genevieve, Bertha, Halong, Iselle - were either produced or elevated. Within an additional 24 hours, the NOAA Tsunami Warning Center a 7.2 magnitude earthquake hit near Lorengau, Papua New Guinea at 00:22:03 UTC, August 3rd 2014. No reports of damage or injury at this time.
25 FIREBALLS REPORTED
speed: 444.4 km/sec
density: 3.4 protons/cm3
potentially Hazardous Asteroids (PHAs) are space rocks larger than approximately 100m that can come closer to Earth than 0.05 AU. None of the known PHAs is on a collision course with our planet, although astronomers are finding new ones all the time.