SOLAR WEATHER
and some interesting space stuff

2009

compiled by Dee Finney

updated 8-31-09

JANUARY - FEBRUARY - MARCH - APRIL - MAY  - JUNE - JULY -
 

AUGUST - SEPTEMBER - OCTOBER - NOVEMBER - DECEMBER

THIS COMPILATION IS BEING DONE IN HONOR OF KENT STEADMAN
OF  www.cyberspaceorbit.com  who left his earthly abode in 2008

2008 SOLAR WEATHER

PAGE 8 - AUGUST 2009

On January 6, 2009 there were 1014 potentially hazardous asteroids.
On February 2, 2009, there were 1019 potentially hazardous asteroids.
On March 2nd, there were 1033 potentially hazardous asteroids.
On April 8th, there were 1050 potentially hazardous asteroids.
On May 3, there were 1054 potentially hazardous asteroids.
On June 2, there were 1061 potentially hazardous asteroids
On July 23rd, there are 1067 potentially hazardous asteroids.
 
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.
On August 4, 2009 there were 1067 potentially hazardous asteroids.
August 2009 Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2009 MC9
Aug. 7
70.3 LD
16
1.2 km
2009 OF
Aug. 8
15.4 LD
18
220 m
2007 RQ17
Aug. 9
8.4 LD
17
130 m
2000 LC16
Aug. 17
75.6 LD
14
2.0 km
2006 SV19
Aug. 21
59.2 LD
16
1.3 km

Notes: LD means "Lunar Distance." 1 LD = 384,401 km, the distance between Earth and the Moon. 1 LD also equals 0.00256 AU. MAG is the visual magnitude of the asteroid on the date of closest approach.

 


GOES 8 MAGNETOMETER MONITOR
GOES 8 SATELLITE DATA
CURRENT SOLAR FLARE DATA

CURRENT SPACE WEATHER DATA
CURRENT SOLAR X-RAY DATA
LASCO IMAGES
SOHO IMAGES
 

A Triple Sunrise Over Gdansk Bay
Credit & Copyright: Barry & Noemi Diacon (McMaster U.)

Explanation: How can the same Sun rise three times? Last month on Friday, 2009 July 10, a spectacular triple sunrise was photographed at about 4:30 am over Gdansk Bay in Gdansk, Poland. Clearly, our Sun rises only once. Some optical effect is creating at least two mirages of the Sun -- but which effect? In the vast majority of similarly reported cases, mirages of the brightest object in the frame can be traced to reflections internal to the camera taking the images. Still, the above image is intriguing because a sincere photographer claims the effect was visible to the unaided eye, and because the photographer took several other frames that show variants of the same effect. Therefore, polite readers are invited to debate whether the above image captures a particularly spectacular example of common reflections inside a standard digital camera, shows one of the most spectacular examples of atmospheric lensing yet recorded, or was caused by something completely different.

 

NEBULA - THE RIGHT HAND OF APOLLO

TOWARD THE END OF TIME
IT'S THE DANGER OF THE SUN

Explore the Sunspot Cycle

 

8-31-09 - Sunspot finally showed up.
 
NEW SUNSPOT: A new sunspot is emerging about 15o north of the sun's equator: map. Pete Lawrence sends this picture from his backyard observatory in Selsey, UK:

"It is small, but a welcome sight, especially after the current long run of no surface activity," he says.

Indeed, if this active region consolidates into a true dark-cored sunspot, it will break a string of nearly 52 spotless days, one of the longest quiet spells of the current solar minimum. Readers with solar telescopes are encouraged to monitor developments.


VANISHING RINGS:
On Sept. 4, 2009, Saturn will turn its rings edge-on to Earth, and for the first time in 14 years they will seem to disappear. "To mark the occasion I've made an animation combining six years of Saturn observations," says New York amateur astronomer Alan Friedman. "It shows the changing plane of the ring system as viewed from my Buffalo backyard from 2004 to 2009."

"The final frame is constructed from observations I made earlier this year," he explains. "it shows how the planet will appear on Sept. 4th."

Unfortunately, the actual ring plane crossing on Sept. 4th will be practically impossible to observe. "On that day, Saturn will be very close to the sun--only 11o away--and the glare will hide the big event. In the fall of 2009, Saturn will emerge from the glare of the sun in the early morning sky and provide Earth-bound astronomers with our first glimpse of its blue north pole in 14 years."

A solar wind stream flowing
from the indicated coronal hole
could reach Earth on or about
Sept. 3rd.
Credit: SOHO Extreme UV Telescope

Current conditions

Solar wind
speed: 401.5 km/sec
density: 1.1 protons/cm3
explanation | more data
Updated: Today at 0315 UT

X-ray Solar Flares
6-hr max: A0
2355 UT Aug31
24-hr: A0
0030 UT Aug31
explanation | more data
Updated: Today at: 2355 UT

 

8-30-09 - No sunspots today

Current conditions

Solar wind
speed: 450.6 km/sec
density: 1.3 protons/cm3
explanation | more data
Updated: Today at 2306 UT

X-ray Solar Flares
6-hr max: A0
2305 UT Aug30
24-hr: A0
0915 UT Aug30
explanation | more data
Updated: Today at: 2305 UT

SOLAR SURPRISE: Even during the deepest solar minimum in a century, the sun has the capacity for surprise. Larry Alvarez got one yesterday when he bent over the eyepiece of his solar telescope in Flower Mound, Texas. "I thought it would be just another day with a vanilla-wafer solar disk, but I was in for a blazing shock when I checked out the edge of the sun," he says. "There was a huge worm popping out of the apple--a prominence of magnificent proportions!" Here is what he saw:

View a video of the prom in action!

"What a doozy," he says. "I watched the prominence for more than two hours and captured many good images." The video he made is a must-see (DivX required).

Realtime images from the Solar and Heliospheric Observatory indicate that the prominence remains active. Readers with solar telescopes should take a look. It's no longer a surprise, but still a doozy.

images: from Michael Borman of Evansville, Indiana; from Matt Wastell of Brisbane, Australia; from Pavol Rapavy of Observatory Romavska Sobota, Slovakia; from Mark Townley of Brierley Hill, West Midlands, UK; from Stephen Ames of Hodgenville, KY; from Fabio Mariuzza of Biauzzo-Codroipo, Italy; from Cai-Uso Wohler of Bispingen, Germany; from Emiel Veldhuis of Zwolle, the Netherlands; from Francisco A. Rodriguez of Cabreja Mountain Observatory, Vega de San Mateo, Gran Canaria, Canary Islands; from Gianfranco Meregalli of Milano, Italy;

This photos is from LASCO images
http://sohowww.nascom.nasa.gov/data/realtime/realtime-c2.html

 

8-29-09 - No sunspots today

Current conditions

Solar wind
speed: 358.3 km/sec
density: 2.2 protons/cm3
explanation | more data
Updated: Today at 2344 UT

X-ray Solar Flares
6-hr max: A0
2340 UT Aug29
24-hr: A0
0320 UT Aug29
explanation | more data
Updated: Today at: 2340 UT

ARCTIC AURORAS: There are some places on Earth where all you have to do to see the Northern Lights is ... to want to. The Inuit village of Salluit in Nunavik, Canada, is such a place. On most clear nights at least a hint of auroras--and often much more than a hint--can be found in the sparkling midnight sky. Salluit resident Sylvain Serre took this picture on August 27th:

"With a clear sky and very good weather, I decided to go outside and take some pictures of the Northern Lights--and there they were," he says.

Salluit is located under Earth's persistent auroral oval, a luminous ring circumscribing the north magnetic pole. Our planet's magnetic field guides particles from space into the oval and voila!--Northern Lights. No geomagnetic storm is required.

August 2009 Aurora Gallery
[
previous Augusts: 2008, 2007, 2006, 2005, 2004, 2003, 2002, 2001]


 

8-28-09 - No sunspots today

Current conditions

Solar wind
speed: 320.7 km/sec
density: 0.8 protons/cm3
explanation | more data
Updated: Today at 2344 UT

X-ray Solar Flares
6-hr max: A0
2340 UT Aug28
24-hr: A0
2340 UT Aug28
explanation | more data
Updated: Today at: 2340 UT

 

8-27-09 - No sunspots today

Current conditions

Solar wind
speed: 381.8 km/sec
density: 3.8 protons/cm3
explanation | more data
Updated: Today at 2344 UT

X-ray Solar Flares
6-hr max: A0
2340 UT Aug27
24-hr: A0
2340 UT Aug27
explanation | more data
Updated: Today at: 2340 UT

LUNAR OCCULTATION: On Thursday, Aug. 27th, the half Moon will pass directly in front of first-magnitude star Antares. The event is best seen from the Atlantic side of North America. Small telescopes pointed at the Moon will show Antares vanish behind the Moon's dark limb around 4:30 pm EDT, all framed by afternoon blue sky. [time tables]

SOLAR ACTIVITY: In the pits of a century-level solar minimum, the sun is setting new records for quiet. But really, how quiet can a 1027-ton nuclear explosion (a star) ever be? The Solar and Heliospheric Observatory recorded some lively action on August 25th and 26th:

The 42-hour time-lapse movie shows a prominence, a swirling cloud of hydrogen held up unsteadily by solar magnetic fields. Prominences appear to be the one form of solar activity that continues apace even when sunspots are absent. Readers with solar telescopes, for a good show train your optics on the edge of the sun.

more images: from Joe Bartolick of Livermore, California; from Michael Buxton of Ocean Beach, California; from Adrian Guzman of San Jose, CA; from Richard Bailey of Barham, Kent, UK; from Monty Leventhal of Sydney. Australia; from Stephen Ames of Hodgenville, Kentucky; from Pavol Rapavy of Observatory Rimavska Sobota, Slovakia; from Fabio Mariuzza of Biauzzo, Codroipo, Italy

 

8-26-09 - No sunspots today

Current conditions

Solar wind
speed: 367.3 km/sec
density: 1.6 protons/cm3
explanation | more data
Updated: Today at 2344 UT

X-ray Solar Flares
6-hr max: A0
2340 UT Aug26
24-hr: A0
2340 UT Aug26
explanation | more data
Updated: Today at: 2340 UT

 

8-25-09 - No sunspots today

Current conditions

Solar wind
speed: 354.2 km/sec
density: 1.2 protons/cm3
explanation | more data
Updated: Today at 1342 UT

X-ray Solar Flares
6-hr max: A0
1340 UT Aug25
24-hr: A0
1340 UT Aug25
explanation | more data
Updated: Today at: 1340 UT

ETERNAL DARKNESS: For years, planetary scientists have speculated about places on the Moon where the sun never shines. NASA may have just found one of them. Behold the inky depths of Crater Erlanger:

NASA's Lunar Reconnaissance Orbiter (LRO) flew over the 10-km crater last week and took a look inside. It was pure shadow. Crater Erlanger is near the Moon's north pole. Because the Moon's spin axis is tilted only 1.5 degrees, sunlight cannot surmount the crater's steep rim to flood the interior.

What lies inside the darkness? An exciting possibility is frozen water. Temperatures in the dark bottom could be as low as -370 Fahrenheit, cold enough to keep ice from sublimating even in hard lunar vacuum. Ice in dark craters could be an invaluable resource for future human explorers. Just melt and drink. Or split H2O into hydrogen for rocket fuel and oxygen for breathing. Water also makes an excellent radiation shield. Two spacecraft, the LRO and India's Chandrayaan-1 probe, are pinging the crater using onboard radars to learn more about Erlanger's hidden deposits. Get the full story from Arizona State University.

 

8-24-09 - No sunspots today

WHO NEEDS THEM? Not all forms of solar activity require sunspots. Throughout the weekend, amateur astronomers monitored a huge prominence surging along the sun's northeastern limb. This morning it erupted:

Prominences are clouds of red-hot hydrogen held above the sun's surface by solar magnetic fields. Sometimes those fields become unstable and erupt, hurling the cloud into space. Such was the case today, Aug. 24th. The Solar and Heliospheric Observatory recorded the action from beginning to end in a 36-hour time-lapse movie.

During the maximum phase of the solar cycle, an eruption like this might be lost in the hubbub of sunspots, solar flares, and geomagnetic storms. But now....? Deep solar minimum does have its advantages.

Current conditions

Solar wind
speed: 359.6 km/sec
density: 2.3 protons/cm3
explanation | more data
Updated: Today at 2345 UT

X-ray Solar Flares
6-hr max: A0
2340 UT Aug24
24-hr: A0
2340 UT Aug24
explanation | more data
Updated: Today at: 2340 UT

 

8-23-09 - No sunspots today

Current conditions

Solar wind
speed: 422.6 km/sec
density: 2.2 protons/cm3
explanation | more data
Updated: Today at 2345 UT

X-ray Solar Flares
6-hr max: A0
2340 UT Aug23
24-hr: A0
0335 UT Aug23
explanation | more data
Updated: Today at: 2340 UT

 

8-22-09

Hodgenville, KY Details:

A large set of complex proms spanning almost 1/4 of the limb is gracing the NW limb. A very clear loop part of the group...

HUGE PROMINENCE: A solar prominence big enough to swallow ten planet Earths is dancing along the northeastern limb of the sun today. Readers with solar telescopes should take a look.

images: from Les Cowley of the United Kingdom; from Cai-Uso Wohler of Bispingen, Germany; from Stephen Ames of Hodgenville, Kentucky

ARE SUNSPOTS DISAPPEARING? Sunspots are made of magnetism. The "firmament" of a sunspot is not matter but rather a strong magnetic field that appears dark because it blocks the upflow of heat from the sun's fiery depths. Without magnetism, there would be no sunspots.

That's what makes the following graph a little troubling:

According to Bill Livingston and Matt Penn of the National Solar Observatory in Tucson, Arizona, sunspot magnetic fields are waning. The two respected solar astronomers have been measuring solar magnetism since 1992. Their technique is based on Zeeman splitting of infrared spectral lines emitted by iron atoms in the vicinity of sunspots. Extrapolating their data into the future suggests that sunspots could completely disappear within decades. That would be a bummer for Spaceweather.com.

Don't count out sunspots just yet, however. While the data of Livingston and Penn are widely thought to be correct, far-reaching extrapolations may be premature. This type of measurement is relatively new, and the data reaches back less than 17 years. "Whether this is an omen of long-term sunspot decline, analogous to the Maunder Minimum, remains to be seen," they caution in a recent EOS article.

One thing is certain. Solar Minimum is a lot more interesting than it sounds: more.

Current conditions

Solar wind
speed: 508.7 km/sec
density: 2.0 protons/cm3
explanation | more data
Updated: Today at 2345 UT

X-ray Solar Flares
6-hr max: A0
2340 UT Aug22
24-hr: A0
0025 UT Aug22
explanation | more data
Updated: Today at: 2340 UT

 

8-21-09 - QUIET SUN: According to NOAA sunspot counts, the longest stretch of spotless suns during the current solar minimum was 52 days in July, August and Sept. of 2008. The current spate of blank suns is putting that record in jeopardy. There have been no sunspots for almost 42 days and there are none in the offing. Deep solar minimum continues.

Current conditions

Solar wind
speed: 476.5 km/sec
density: 1.8 protons/cm3
explanation | more data
Updated: Today at 2340 UT

X-ray Solar Flares
6-hr max: A0
2340 UT Aug21
24-hr: A0
0745 UT Aug21
explanation | more data
Updated: Today at: 2340 UT

FLYING ISLANDS: On August 14th, gravity was revoked in the Netherlands--or so it seemed when photographer Rik ter Horst looked out across the water and saw Schiermonnikoog Island floating in mid-air:

"It was just a mirage," he says. Temperature gradients in the air over the cool, open water caused light from the island and its surroundings to curve in unusual ways en route to the camera. The apparent gap between the island and the sea is actually an upside-down image of the sky above. Note the hint of antenna pointing into the water. But don't look too closely, cautions Horst. "You might start believing islands can fly."

more images: from Peter von Bagh of Porvoo, Finland; from Mila Zinkova of San Francisco, California; from Ivar Marthinusen of Storlien, Sweden; from Becky Ramotowski of Amarillo, Texas
 

8-20-09 - BLANK SUN: The sun is entering its 41st consecutive day without sunspots. This remarkable string of blank suns shows that we are still in the pits of the deepest solar minimum in a century. If the streak continues for 11 more days, it will match the longest blank spell of the current cycle.

Current conditions

Solar wind
speed: 517.4 km/sec (This is the highest wind speed this year)
density: 1.4 protons/cm3
explanation | more data
Updated: Today at 2347 UT

X-ray Solar Flares
6-hr max: A0
2345 UT Aug20
24-hr: A0
2345 UT Aug20
explanation | more data
Updated: Today at: 2345 UT

8-19-09  No sunspots today - 39 days without a sunspot

Current conditions

Solar wind
speed: 431.6 km/sec
density: 9.3 protons/cm3
explanation | more data
Updated: Today at 2146 UT

X-ray Solar Flares
6-hr max: A0
2140 UT Aug19
24-hr: A0
2140 UT Aug19
explanation | more data
Updated: Today at: 2140 UT
 

The sun lives! More out of hope than expectation I took an H-alpha look at the sun with my Solarmax60 this afternoon, usually a time of poor seeing. Remarkably the image was steady and this complex prominence was evolving on the NW limb. Eyepiece sketch at 50X.

  JUPITER MOON MOVIE: Four hundred years ago when Galileo discovered the moons of Jupiter, the satellites appeared in his primitive telescope as tiny, almost infinitesimal specks of light pirouetting around the giant planet. Their discovery transformed 17th century cosmology and made Galileo famous, but he never saw them as anything more than star-like pinpricks. The "Galilean satellites" were second-class citizens in the heirarchy of known worlds.

What would Galileo say now?

On August 16th, Philippine astrophotographer Christopher Go used a modern 11-inch Celestron telescope to photograph Io casting its shadow on Ganymede. Click on the image to launch the movie:

"I captured this rare event through a hole in the clouds," says Go. "It was a lucky clearing!"

In the movie, Io and Ganymede reveal themselves as fully-formed worlds with surface markings and a spherical shape. Io's circular shadow cuts a dark swath across Ganymede, transforming that giant moon (it is larger than Mercury) into a succession of crescents rarely seen by observers. Indeed, as far as we know, no telescope on Earth or space has ever photographed one of Jupiter's moons casting its circular shadow so clearly across another.

"While imaging the shadow transit, I took the time to photograph Jupiter itself," says Go. "The Great Red Spot, an anticyclone twice the size of Earth, was very prominent."

At this point, one imagines Galileo would jump up and exclaim--"bring me a telescope!" If only we could. August 2009 is a superb time to watch the giant planet. Jupiter is at its closest to Earth and outshines every star in the night sky. Backyard optics reveal giant storms, clouds, moons, moon shadows and occasionally an explosive surprise. The place to look is here.

 

8-18-09 - No sunspots today

Current conditions

Solar wind
speed: 340.4 km/sec
density: 5.8 protons/cm3
explanation | more data
Updated: Today at 2346 UT

X-ray Solar Flares
6-hr max: A0
2340 UT Aug18
24-hr: A0
2340 UT Aug18
explanation | more data
Updated: Today at: 2340 UT

HERE IS SOHO ANOMALY FROM 2005 - SEE MORE FROM 2009 BELOW

8-17-09

Current conditions

Solar wind
speed: 331.3 km/sec
density: 8.1 protons/cm3
explanation | more data
Updated: Today at 2137 UT

X-ray Solar Flares
6-hr max: A0
2130 UT Aug17
24-hr: A0
2130 UT Aug17
explanation | more data
Updated: Today at: 2130 UT

WHAT IS IT?  THESE ARE THREE CONSECUTIVE IMAGES OFF THE SOHO PAGE FROM YESTERDAY

It was from this page:  http://sohodata.nascom.nasa.gov/cgi-bin/data_query_search_url?Session=web&Resolution=2&Display=Images&NumImg=30&Types=instrument=LASCO:detector=C3


 
BUSY MORNING: Monday began with a flurry of activity in the eastern sky. Theenter"> .

"Wow, what a show!" says Dorman.

Elsewhere, the Moon-Venus conjunction provided a backdrop for rocket launches and other forms of air travel. It was a busy morning, indeed.

 

8-16-09 - No sunspots today<

Solar wind
speed: 274.6 km/sec
density: 2.3 protons/cm3
explanation | more data
Updated: Today at 0406 UT

X-ray Solar Flares
6-hr max: A0
2355 UT Aug15
24-hr: A0
2355 UT Aug15
explanation | more data
Updated: Today at: 2355 UT

MORNING SHOW: If you wake up before sunrise this weekend, look east. The crescent Moon is approaching Venus for a Monday-morning close encounter. The International Space Station is likely to be there, too. So be alert for a gathering of bright lights in the dawn sky; it's a great way to start the day. Sky maps: Aug. 16th, 17th.

PERSEIDS NEWS

According to the International Meteor Organization, the shower peaked an extraordinary three times. The first peak, around 0800 UT on August 12th, was caused by Earth hitting a filament of dust shed by Perseid parent Comet Swift-Tuttle in 1610. The second peak, around 1800 UT on August 12th, was another cloud of dust from Comet Swift-Tuttle nudged toward Earth by the gravity of Saturn. The third peak, around 0600 UT on August 13th, is a mystery. Researchers are working now to "reverse-forecast" the shower and figure out the source of the third outburst.

NOTE:  In California: I sat out for 3 hours and only saw one meteor - and a small one at that.

td>8-15-09 - No sunspots today

Current conditions

Solar wind
speed: 275.9 km/sec
density: 2.9 protons/cm3
explanation | more data
Updated: Today at 2346 UT

X-ray Solar Flares
6-hr max: A0
2340 UT Aug15
24-hr: A0
2340 UT Aug15
explanation | more data
Updated: Today at: 2340 UT

Storm Clouds Found on Saturn's Moon Titan

The climate on Saturn's moon, Titan, resembles the Earth, but
instead of a water cycle it rains methane. Here, Ontario Lacus, a
 methane lake near to Saturn's moon Titan's South Pole is shown.

Clara Moskowitz ,
Space.com

A tropical storm was not what astronomers expected to see when they pointed their telescopes toward the equator of Saturn's moon Titan last summer.
 
But that's exactly what they found on this beguiling moon, home to a weather system both eerily familiar and perplexingly strange. The discovery was announced Wednesday.

In many ways Titan's climate resembles that of Earth, but instead of a water cycle, Titan has a methane cycle. Clouds, rain and lakes all exist on Titan, but they are all made of methane. In the moon's frigid climate, any water is frozen into rock-hard ice.
Clouds of vaporized methane are not uncommon on Titan, though they have never before been observed in Titan's tropics. But in April 2008, astronomers using the Gemini North telescope and NASA's Infrared Telescope Facility in Hawaii spotted a severe storm covering almost 2 million square miles (3 million square km) over the equator.
"The models predicted that the equatorial region should be very dry and should not support cloud formation," said astronomer Henry Roe of Lowell Observatory in Arizona. "But this episode created clouds over both the equator and the south pole. We don't know what set off that sequence, but something gave a pretty good kick to the atmosphere."
Scientists suspect the storm's trigger may have been some kind of geologic activity on the moon's surface, such as a geyser or new mountain range forming. Atmospheric effects may also have set off the storm.

The situation is a new wrinkle in the study of this complex moon.
 
"It's an amazing place because it is deeply familiar to us, being form Earth, in terms of the processes - clouds forming, rainfall, carved out channels on the surface, huge fields of what look like sand dunes," Roe told SPACE.com. "But the materials that are involved are quite alien."

Scientists hope to learn more as Saturn's 30-year-long orbit plays out a full rotation of seasons on the moon. NASA's Cassini spacecraft is currently in orbit around Saturn, but it only flies by Titan once every six weeks or so. In the meantime, ground-based telescopes can keep a near-steady eye on the moon.

"We really need to keep observing Titan in detail for many more years in order to get a true understanding of how its seasons change," Roe said.

The researchers, led by Emily Schaller of the Institute for Astronomy in Hawaii (now at the University of Arizona), detail the new finding in the August 13 issue of the journal Nature.

 

8-14-09 - No sunspots today

Current conditions

Solar wind
speed: 302.8 km/sec
density: 1.6 protons/cm3
explanation | more data
Updated: Today at 2347 UT

X-ray Solar Flares
6-hr max: A0
2340 UT Aug14
24-hr: A0
0720 UT Aug14
explanation | more data
Updated: Today at: 2340 UT

GOOD SHOW: Veteran meteor watchers say the Perseids of 2009 were the best in years.
One look at this photo shows why:

NASA astronomers Danielle Moser and Bill Cooke made the composite of 130+ Perseids that flew over the Marshall Space Flight Center on August 12th. "We recorded a bright meteor or fireball every 3 minutes--a fabulous rate," says Cooke. Their meteor detection system consists of two cameras separated by 100 miles--one in Alabama and one in Georgia. The wide baseline allows Cooke and his team to triangulate the trajectory of meteoroids with some accuracy. Here is a geographic map of the Perseids they saw. "The stars really did fall on Alabama!" he says.

Worldwide, observers counted as many as 200 Perseids per hour. Some of the prettiest may be found in the photo gallery.

UPDATED: 2009 Perseid Photo Gallery
[
Science@NASA: The Perseids are Coming, Horse Flies and Meteors]

PERFECT NIGHT: Robert Postma of Fort Simpson, Canada, went outside on August 12th to see the Perseids and got more than he bargained for. "I was treated to a triple whammy," he says. "The auroras came out, noctilucent clouds lit up the horizon, and a meteor streaked across the sky. It was a perfect night."

And an unlikely one....

The Perseids and, to a lesser degree, the noctilucent clouds were expected. But where did the auroras come from? There was no solar flare or gust of solar wind to spark the display. It appears to have been an unprovoked spasm of geomagnetic activity, which appeared on its own schedule, in the middle of the best meteor shower in years.

Sometimes it just pays to be outside. Keep looking up!

 

8-13-09 - No sunspots today

Current conditions

Solar wind
speed: 352.4 km/sec
density: 6.2 protons/cm3
explanation | more data
Updated: Today at 1255 UT

X-ray Solar Flares
6-hr max: A0
1255 UT Aug13
24-hr: A0
0605 UT Aug13
explanation | more data
Updated: Today at: 1255 UT

PLANET HUNTERS from the UK have discovered the largest EXOPLANET yet, and its uniqueness doesn't end there. Dubbed WASP-17, this extra large world is twice the size of Jupiter but is super-lightweight, "as dense as expanded polystyrene" one astronomer said. Plus it is going the WRONG WAY around its home sun, making it the first exoplanet known to have a
retrograde orbit. As a likely a victim of planetary billiards, astronomers say this unusual planet casts new light on how planetary systems form and evolve.

ASTRONOMERS SAY the planet must have flipped direction after a near miss with another huge "big brother" planet swung it around like a slingshot. Astronomers have long wondered why some EXTRASOLAR PLANETS are far bigger than expected, and WASP-17 points to the explanation. Scattered into a highly elliptical, retrograde orbit, it would have been subjected to intense tides. Tidal compression and stretching would have heated the gas-giant planet to its current, hugely bloated extent. -- Written by Nancy Atkinson

WASP-17b: an ultra-low density planet in a probable retrograde orbit

Abstract: We report the discovery of the transiting giant planet WASP-17b, the least-dense planet currently known. It is 1.6 Saturn masses but 1.5-2 Jupiter radii, giving a density of 6-14 per cent that of Jupiter. WASP-17b is in a 3.7-day orbit around a sub-solar metallicity, V = 11.6, F6 star. Preliminary detection of the Rossiter-McLaughlin effect suggests that WASP-17b is in a retrograde orbit (lambda ~ -150 deg), indicative of a violent history involving planet-planet or planet-star scattering.
WASP-17b's bloated radius could be due to tidal heating resulting from recent or ongoing tidal circularisation of an eccentric orbit, such as the highly eccentric orbits that typically result from scattering interactions. It will thus be important to determine more precisely the current orbital eccentricity by further high-precision radial velocity measurements or by timing the secondary eclipse, both to reduce the uncertainty on the planet's radius and to test tidal-heating models. Owing to its low surface gravity, WASP-17b's atmosphere has the largest scale height of any known planet, making it a good target for transmission spectroscopy.
Comments: 9 pages, 7 figures, 4 tables, submitted to ApJ
Subjects: Earth and Planetary Astrophysics (astro-ph.EP)
  arXiv:0908.1553v1 [astro-ph.EP]

Huge new planet tells of game of planetary billiards

A team of scientists has found a new planet which orbits the wrong way around its host star. The planet, named WASP-17, and orbiting a star 1000 light years away, was found by the UK's WASP project in collaboration with Geneva Observatory. The discovery, which casts new light on how planetary systems form and evolve, is being announced today (12th August) in a paper submitted to Astrophysical Journal

An artist's impression of a transiting exoplanet
An artist's impression of a transiting exoplanet
Credit:NASA/Hubble

Since planets form out of the same swirling gas cloud that creates a star, they are expected to orbit in the same direction that the star spins. Graduate students David Anderson, of Keele University, and Amaury Triaud, of Geneva Observatory, were surprised to find that WASP-17 is orbiting the wrong way, making it the first planet known to have a ``retrograde'' orbit. The likely explanation is that WASP-17 was involved in a near collision with another planet early in its history.

WASP-17 appears to have been the victim of a game of planetary billiards, flung into its unusual orbit by a close encounter with a ``big brother'' planet. Professor Coel Hellier, of Keele University, remarks: "Shakespeare said that two planets could no more occupy the same orbit than two kings could rule England; WASP-17 shows that he was right.”

David Anderson added “Newly formed solar systems can be violent places. Our own moon is thought to have been created when a Mars-sized planet collided with the recently formed Earth and threw up a cloud of debris that turned into the moon. A near collision during the early, violent stage of this planetary system could well have caused a gravitational slingshot, flinging WASP-17 into its backwards orbit.”

The first sign that WASP-17 was unusual was its large size. Though it is only half the mass of Jupiter it is bloated to nearly twice Jupiter's size, making it the largest planet known.

Astronomers have long wondered why some extra-solar planets are far bigger than expected, and WASP-17 points to the explanation. Scattered into a highly elliptical, retrograde orbit, it would have been subjected to intense tides. Tidal compression and stretching would have heated the gas-giant planet to its current, hugely bloated extent. "This planet is only as dense as expanded polystyrene, seventy times less dense than the planet we're standing on", notes Prof. Hellier.

Professor Keith Mason, Chief Executive of the Science and Technology Facilities Council, which funded the research, said, “This is a fascinating new find and another triumph for the WASP team. Not only are they locating these far flung and mysterious planets but revealing more about how planetary systems, such as our own Solar System, formed and evolved. The WASP team has proved once again why this project is currently the World's most successful project searching for transiting exoplanets.”

WASP-17 is the 17th new exoplanet (planet outside our solar system) found by the Wide Area Search for Planets (WASP) consortium of UK universities. The WASP team detected the planet using an array of cameras that monitor hundreds of thousands of stars, searching for small dips in their light when a planet transits in front of them. Geneva Observatory then measured the mass of WASP-17, showing that it was the right mass to be a planet. The WASP-South camera array that led to the discovery of WASP-17 is hosted by the South African Astronomical Observatory.

Notes to editors

Artist's impression of two close extra-solar planets.
Credit: KASI/CBNU/ARCSEC.

An artist's impression of a transiting exoplanet.
Credit: ESA C Carreau

An artist's impression of a transiting exoplanet.
Credit: ESA C Carreau

An artist's impression of a transiting exoplanet.
Credit NASA/Hubble

The discovery paper for WASP-17 is available at astro-ph and has been submitted to Astrophysical Journal. A forthcoming paper led by Amaury Triaud confirms the retrograde orbit and studies the orbital dynamics in greater depth.

The WASP Project (Wide Area Search for Planets) is the UK's leading extra-solar planet detection program and includes Keele University, St. Andrews University, Queen's University Belfast, Leicester University, the Open University, and the Isaac Newton Group. WASP collaborates with the Geneva Observatory, Switzerland, who have a world-leading programme of planet discovery using the Coralie and HARPS spectrographs.

Shakespeare's Henry IV, Part 1, Act 5, Scene 4:
"Two stars keep not their motion in one sphere, Nor can one England brooke a double reign, Of Harry Percy, and the Prince of Wales."
(The word "stars" referred to planets in the cosmology of Shakespeare's time.)

"Transit": Term for a planet passing in front of its star, blocking a tiny fraction of its light.

"Retrograde": Term for an orbit in the opposite direction to the rotation of the star being orbited. All Solar System planets are in ``prograde'' orbits around our sun, orbiting in the same direction that the sun is spinning. "Extra-solar planet": A planet not in our Solar System, instead orbiting another star.

"Elliptical orbit": While the planets in our solar system have orbits that are close to circular, planet orbits can also trace out long, thin ellipses. "Tidal interactions": Just as our moon pulls the earth's oceans, causing tides, a star's gravity would cause tidal bulges on any planet nearby.

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Page last updated: 12 August 2009 by Julia Short
PERSEID OUTBURST: Last night, amateur astronomer Chris Peterson witnessed a flurry of bright Perseids streaking over his observatory in Guffey, Colorado. "Here are the 96 brightest recorded by my all-sky camera," he says.

Peterson plotted the frequency of events and found "a clear outburst of meteor activity around 0800 UT on Aug. 12th." That's exactly when NASA's Meteoroid Environment Office said Earth would run into a filament of dust shed by Perseid parent Comet Swift-Tuttle in 1610. Their prediction beautifully matches actual worldwide meteor counts--a demonstration that meteor science has moved into the realm of precision forecasting.

The outburst is over but the meteor shower is still underway. Stray comet dust is hitting Earth's atmosphere at 130,000 mph, producing an drizzle of 50 or more Perseids per hour. If it is dark where you live, be alert for shooting stars.

8-12-09

Current conditions

Solar wind
speed: 356.2 km/sec
density: 5.5 protons/cm3
explanation | more data
Updated: Today at 0727 UT

X-ray Solar Flares
6-hr max: A0
0720 UT Aug12
24-hr: A0
0720 UT Aug12
explanation | more data
Updated: Today at: 0720 UT

POSSIBLE PERSEID METEOR OUTBURST: This year's Perseid meteor shower could be even better than usual.  According to NASA's Meteoroid Environment Office, a  filament of comet dust has drifted across Earth's path and when Earth passes through it, sometime between 0800 and 0900 UT (1 - 2 am PDT) on August 12th, the Perseid meteor rate could surge to twice its normal value. 

POSSIBLE PERSEID OUTBURST: This year's Perseid meteor shower could be even better than usual. "A filament of comet dust has drifted across Earth's path and when Earth passes through it, sometime between 0800 and 0900 UT (1 - 2 am PDT) on August 12th, the Perseid meteor rate could surge to twice its normal value," says Bill Cooke of NASA's Meteoroid Environment Office. The following profile is based on the debris stream models of veteran forecasters Jeremie Vaubaillon and Mikhail Maslov:

The filament was shed by Perseid parent comet Swift-Tuttle in the year 1610, and this is one of Earth's first encounters with it. "In addition," notes Cooke, "the main Perseid debris stream, which we run into every year, may be denser than normal due to a gravitational enhancement by Saturn. The total combination of these effects could result in as many as 200 meteors per hour (ZHR)."

Bright moonlight will overwhelm the outburst's fainter Perseids, but even a fraction of 200 is a good show. Science@NASA's "The Perseids are Coming" offers observing tips and sky maps.

BARCELONA, SPAIN - by Pepe Manteca

PERSEIDS NOW! The Perseid meteor shower is about to peak. The show begins after sunset on Tuesday, August 11th, and continues until dawn on Wednesday, August 12th. During the long night, sky watchers could see dozens of meteors per hour.

are seeing some bright ones," he says.

A time of particular interest is 0800 UT (1 am PDT) on August 12th. That's when Earth is expected to pass through a denser-than-usual filament of dust from the shower's parent Comet Swift-Tuttle. For an hour or so, rates could surge to 200 per hour. Bright moonlight will blot out many of those Perseids, but even a fraction of 200 is a good show. Observing tips may be found in the Science@NASA story "The Perseids are Coming."

UPDATED: 2009 Perseid Photo Gallery
[
Previous Perseids: 2008, 2007, 2006, 2005, 2004, 2001]

 

8-11-09 No sunspots today

Current conditions

Solar wind
speed: 349.3 km/sec
density: 6.5 protons/cm3
explanation | more data
Updated: Today at 2346 UT

X-ray Solar Flares
6-hr max: A0
2340 UT Aug11
24-hr: A0
2340 UT Aug11
explanation | more data
Updated: Today at: 2340 UT

 

8-10-09 - No sunspots today

Current conditions

Solar wind
speed: 391.1 km/sec
density: 3.7 protons/cm3
explanation | more data
Updated: Today at 0646 UT

X-ray Solar Flares
6-hr max: A0
0640 UT Aug10
24-hr: A0
0640 UT Aug10
explanation | more data
Updated: Today at: 0640 UT

TOP SECRET: Not every light that streaks across the night sky is a Perseid. Some of them are spy satellites. Here's one gliding over Maghaberry, Northern Ireland, on August 10th:

"It was Lacrosse 3," reports photographer John McConnell. "Spaceweather's Simple Satellite Tracker predicted a flyby and there it was."

Lacrosse 3 is a top-secret yet easily observed US National Reconnaissance Office spy satellite. It often attracts attention when sunlight glints brightly from its solar panels, rumored to span 45 meters from tip to tip. The solar arrays power a synthetic aperture radar, which can image Earth's surface with meter-resolution even through clouds. Some web sites claim that the radar can also sense objects underground, but that's just speculation.

"I couldn't mistake Lacrosse 3 because it was so bright," says McConnell. "This is even better than Perseids!"

 

8-9-09 - No sunspots today

Solar wind
speed: 396.6 km/sec
density: 3.6 protons/cm3
explanation | more data
Updated: Today at 2346 UT

X-ray Solar Flares
6-hr max: A0
2345 UT Aug09
24-hr: A0
2345 UT Aug09
explanation | more data
Updated: Today at: 2345 UT

PERSEID FIREBALL: "Last night I photographed 17 Perseids," reports John Chumack of Dayton, Ohio. "The best one was a fireball of magnitude -8, about 40 times brighter than Venus. It had a double explosion, too!"

"The Perseid meteor shower is definitely underway," he says.

It should get even better in the nights ahead. Members of the International Meteor Organization are now counting more than 25 Perseids per hour: data. The rate is expected to increase almost 10-fold on the night of August 11th and 12th when Earth passes through a denser-than-usual filament of comet dust crossing Earth's orbit. Oberving tips may be found in the Science@NASA story "The Perseids are Coming."

 

8-8-09 - No sunspots today

Current conditions

Solar wind
speed: 441.9 km/sec
density: 7.5 protons/cm3
explanation | more data
Updated: Today at 2346 UT

X-ray Solar Flares
6-hr max: A0
2340 UT Aug08
24-hr: A0
2340 UT Aug08
explanation | more data
Updated: Today at: 2340 UT

Earth is inside a solar wind
stream flowing from the indicated
coronal hole.
Credit: STEREO-A Extreme UV Telescope

PERSEID UPDATE: The Perseid meteor rate is holding steady at 20 per hour, according to observers from the International Meteor Organization: data. Most of these meteors are difficult to see, however, because bright moonlight is blotting them out. The situation should improve on peak night, August 11th and 12th, when as many as 200 meteors per hour are expected to dash through waning moonlight. Get the full story from Science@NASA.

RADIO PERSEIDS: Awash in moonlight, the Perseid meteor shower is at present not very easy to see. Some observers have given up on looking, choosing instead to monitor the shower by means of radio. This plot from Dave Swan shows how he is counting more than 300 Perseid radio echoes per hour using a Yagi antenna and 55.25 MHz receiver in Bransgore, UK:

In the loudspeaker, each echo sounds like a little "ping." It is the reflection of a distant TV transmitter from the meteor's ionized trail. Forward scatter meteor detection, as this technique is called, is more sensitive than ordinary visual observation. Very small meteoroids are able to create a radio echo without leaving any trace of optical light in the sky. That's why Swan is counting 300 radio Perseids per hour while naked-eye observers are couting no more than about 20. Click here to monitor forward scatter stations around the world.

 

8-7-09 - No sunspots today

Current conditions

Solar wind
speed: 472.8 km/sec
density: 4.3 protons/cm3
explanation | more data
Updated: Today at 2346 UT

X-ray Solar Flares
6-hr max: ff0000"> INTENSIFYING PERSEIDS: The Perseid meteor rate is increasing as Earth plunges deeper into the debris stream of Comet Swift-Tuttle. International Meteor Organization observers are now counting 20 per hour: data. Forecasters say the rate could increase another tenfold to 200 per hour on peak night, Aug. 11th and 12th. Observing tips may be found in the Science@NASA story "The Perseids are Coming."

HOW HIGH IS A PERSEID? Perseid meteors seem so nearby when they fly overhead, but appearances can be deceiving. Consider the following fireball, which lit up the sky above the Marshall Space Flight Center two nights ago:

NASA astronomer Bill Cooke photographed the Perseid using not one but two all-sky cameras located 100 miles apart. The system's wide baseline, which crosses state lines between Alabama and Georgia, allowed him to triangulate the meteor's position and measure its velocity. "It came in at 58.8 km/s (130,000 mph) and disintegrated between 111 and 86 km above Earth's surface," he says.

So far, the dual-camera system has captured seven bright Perseids suitable for analysis. Cooke's histograms of starting and ending heights answer the question, how high is a Perseid?

 

8-6-09 - No sunspots today

Current conditions

Solar wind
speed: 504.9 km/sec
density: 3.1 protons/cm3
explanation | more data
Updated: Today at 2344 UT

X-ray Solar Flares
6-hr max: A0
2340 UT Aug06
24-hr: A0
2340 UT Aug06
explanation | more data
Updated: Today at: 2340 UT

METEOR UPDATE: Perseid meteors are now hitting Earth's upper atmosphere with a speed of 58 to 60 km/s, about 130,000 mph. That's the result of triangulation by a dual-station meteor monitoring system operated by NASA's Meteoroid Environment Office. Last night the system detected five fireballs that provided the data for this speed estimate.

EARLY PERSEIDS: The Perseid meteor shower is slowly intensifying as Earth plunges deeper in Comet Swift-Tuttle's debris stream. On August 4th, amateur astronomer Thomas Ashcraft caught an early arrival using an all-sky camera at his observatory near Santa Fe, New Mexico. Click on the image to play a movie with sound effects:

The "ping" you just heard was a 61.25 MHz TV signal bouncing off the meteor's ionized tail. Ashcraft keeps an antenna trained on the sky so that he can record the echos and lay them down as soundtracks for his all-sky movies. "I'm sure I'll record many more in the days ahead," he says. "Highlights will be posted here."

According to the International Meteor Organization, about 10 Perseids per hour are now streaking across the night sky: data. This number could increase to as many as 200 per hour when Earth crosses an anticipated filament of comet dust around 0800 UT (1 a.m. PDT) on August 12th. Observing tips and a sky map may be found in the Science@NASA story "The Perseids are Coming."

2009 Perseid Meteor Gallery
[
previous Perseids: 2008, 2007, 2006, 2005, 2004, 2001]

 

8-5-09 - No sunspots today

Current conditions

Solar wind
speed: 380.0 km/sec
density: 16.2 protons/cm3
explanation | more data
Updated: Today at 2346 UT

X-ray Solar Flares
6-hr max: A0
2340 UT Aug05
24-hr: A0
1350 UT Aug05
explanation | more data
Updated: Today at: 2340 UT

 

8-4-09 - No sunspots today  - 24 days without a spot

Solar wind
speed: 332.2 km/sec
density: 4.3 protons/cm3
explanation | more data
Updated: Today at 1647 UT

X-ray Solar Flares
6-hr max: A0
1645 UT Aug04
24-hr: A0
1645 UT Aug04
explanation | more data
Updated: Today at: 1645 UT

SWIRLING DEBRIS ON JUPITER: The "Wesley impact cloud" on Jupiter continues to expand and evolve. On August 1st and 2nd, worldwide observers noted that it had transformed from a concentrated, cindery-black spot to an Earth-sized paling swirl. South is up in this just-updated Aug. 3rd image from the cloud's discoverer, Anthony Wesley of Murrumbateman, Australia:

"Polar winds seem to be carrying the main body of the cloud westward (to the right in the photo)," says Wesley. "Also, a small stream of dark material is being pulled down and in the opposite direction--perhaps around a cyclone or some other localized weather feature?"

Researchers are scrambling to study the cloud before it disperses. Light reflected from the debris may hold clues to the nature of the mystery-impactor. "If the cloud's spectra contain signs of water, that would suggest an icy comet. Otherwise, it's probably a rocky or metallic asteroid," says JPL planetary scientist Glenn Orton. Several teams of professional astronomers are working to obtain the data.

Meanwhile, amateur astronomers can monitor the cloud as it shifts and swirls near Jupiter's System II longitude 210°. For the predicted times when it will cross the planet's central meridian, add 2 hours and 6 minutes to Sky and Telescope's predicted transit times for Jupiter's Great Red Spot. [sky map]

more images: from Raffaello Lena of Rome, Italy; from Glenn Jolly of Gilbert, Arizona, USA; from Wah! of Hong Kong; from William Rison of Newburg, Maryland; from Joel Warren of Amarillo, Texas; from David Kolb of Lawrence, Kansas; from Alphajuno of League City, Texas; from Mariano Ribas of Buenos Aires, Argentina; from Giancarlo Ubaldo Nappi of Belo Horizonte, Minas Gerais, Brazil

 

A solar wind stream flowing
from the indicated coronal hole
could reach Earth on or about
 Aug. 7th.
Credit: SOHO Extreme UV Telescope

 

8-3-09 - No sunspots today

Current conditions

Solar wind
speed: 381.7 km/sec
density: 7.4 protons/cm3
explanation | more data
Updated: Today at 2346 UT

X-ray Solar Flares
6-hr max: A0
2340 UT Aug03
24-hr: A0
0020 UT Aug03
explanation | more data
Updated: Today at: 2340 UT

Jupiter Blots Out a Star

This might just be the busiest time in living memory for people who love to observe Jupiter. First the plane of its moons pointed edge-on to Earth, allowing remarkable "mutual events" when the moons eclipse and occult each other.

Then, on July 19th, Australian amateur astronomer Anthony Wesley discovered that a comet or asteroid had struck the giant planet, leaving a dark marking that's still clearly visible. This is just the second time in the 400-year history of telescopic observing that such an event has been clearly documented.

And on the night of August 3-4, Jupiter will cover a 6th-magnitude star — a once-in-a-lifetime occurrence for most locations on Earth. The event occurs roughly from 22:53 Universal Time on August 3rd to 1:00 UT August 4th, varying slightly depending on your location. It happens at prime time for stargazers in Europe and Africa, and is also readily visible in the Middle East and Brazil.

S&T illustration
-->In North America, the occultation can only be seen from New England and the Maritime Provinces — and barely so. In those locations, Jupiter will rise while it's hiding 45 Cap, and will still be extremely low in the sky when the star reappears.

But by amazing good luck, 45 Cap will be masquerading as a fifth moon during a particularly eventful period for Jupiter's Galilean moons. So weather permitting, every telescope owner on Earth will have a chance to see many fascinating events during the days before and after the occultation.

All of these events should be visible through small telescopes if the atmosphere is very steady, but extra aperture and high magnification will improve the views greatly. Try our Javascript utility or our PDF table for details of the moons' interactions with Jupiter. And download a PDF article from the July 2009 issue of Sky & Telescope to see the details of the "mutual events" between the moons.

Aug. 1-2, 10:19 p.m. to 1:48 a.m. PDT, 1:19 to 4:48 a.m. EDT: The first sequence is visible across the Americas. It starts with just three moons visible (not counting 45 Cap), because Ganymede is behind Jupiter. During this period Europa and its shadow pass over Jupiter, Ganymede reappears, and Io disappers.

Aug. 2-3, 9:49 p.m. to 12:25 a.m. PDT, 12:49 to 3:25 a.m. EDT: Again visible across the Americas, a normal transit of Io and its shadow across Jupiter — fairly common but spectacular nonetheless.

Aug. 2, 15:55 to 16:32 UT: Best in eastern Asia and Australia. Io casts its shadow on Europa from 15:55 to 16:02 UT, dimming it 50%. Then Io passes in front of Europa from 16:26 to 16:36 UT, blocking 74% of its surface. Meanwhile, 45 Cap is just 30" to their south.

Aug. 3-4, 22:53 to 4:39 UT, Jupiter rise to 12:39 a.m. EDT: This is the big event. The occultation of 45 Cap is best observed from Europe and Africa, but as you can see in the diagram above, Europa disappears into Jupiter's shadow while the star is hidden, and Io disappears shortly after the star reappears. By 4:39 UT (12:39 a.m. EDT or 9:39 PDT), all three have reappeared from behind Jupiter, but they're still spectacularly close to Jupiter and each other.

Aug. 4, 21:47 to 22:57 UT: In most of Europe and Africa, and much of Asia, Ganymede casts its shadow on Europa, diminishing its light 94%, from 21:47 to 21:59 UT. Then Ganymede clips the edge of Europa from 22:48 to 22:57 UT.

Aug. 4-5, 23:18 to 1:51 UT: In Europe and Africa, a normal transit of Io and its shadow.

Aug. 5, 14:38 to 23:05 UT: A very long sequence of events, best viewed in the Middle East and eastern Africa, but with parts visible across Eurasia and Oceania. A transit of Ganymede and its shadow overlapping a transit of Europa and its shadow, with Io disappearing and reappearing toward the end of the sequence.

 
Posted by Tony Flanders, July 30, 2009

 

8-2-09 - No sunspots today

Current conditions

Solar wind
speed: 370.8 km/sec
density: 13.6 protons/cm3
explanation | more data
Updated: Today at 2346 UT

X-ray Solar Flares
6-hr max: A0
2340 UT Aug02
24-hr: A0
2340 UT Aug02
explanation | more data
Updated: Today at: 2340 UT

LONELY PROMINENCE: Yesterday, Alan Friedman of Buffalo, New York, looked through his solar telescope and actually felt sorry for the sun. "Seeing this solitary prominence, I imagined the sun experiencing a twinge of melancholia ... or perhaps it's my reaction to the seemingly endless solar minimum."

When Friedman took the picture on August 1st, the sun had just entered its 22nd consecutive day of spotlessness--no sunspots for more than three weeks! This is typical of 2009. So far this year, the sun has been blank 77% of the time, confirming the solar minimum of 2008-2009 as a century-class event.

But endless? No. Solar jet streams are beginning to stimulate new-cycle sunspot production--e.g., sunspot 1024 in early July. NOAA forecasters expect solar activity to intensify in late 2009-early 2010 leading to a new solar maximum in 2012-2013. If they're correct, soon, the lonely prominence will be a thing of the past.

 

8-1-09 - No sunspots today

Current conditions

Solar wind
speed: 385.4 km/sec
density: 4.7 protons/cm3
explanation | more data
Updated: Today at 2346 UT

X-ray Solar Flares
6-hr max: A0
2340 UT Aug01
24-hr: A2
0240 UT Aug01
explanation | more data
Updated: Today at: 2340 UT

TOP SECRET: The US National Reconnaisance Office won't confirm that it exists, but last night in Switzerland, astrophotographer Olivier Staiger saw it with his own eyes--the Lacrosse 3 spy satellite:

"As I saw the satellite fly across the sky," says Staiger, "I clearly got the impression that it became quite bright, that it flared, akin to an Iridium flare, so I was curious to see if the flare would show on the photo--and yes it does."

The flare was probably sunlight glinting from the satellite's solar panels, rumored to span 45 meters from tip to tip. The solar arrays are thought to power a synthetic aperture radar, which can image Earth's surface with meter-resolution even through clouds. Some web sites claim that the radar can also sense objects underground, but that's just speculation.

You can see this top-secret satellite for yourself--and maybe catch a flare as it soars overhead. Check the Simple Satellite Tracker for flyby times.

 

SPACE DATABASE ON THIS SITE

DREAMS OF THE GREAT EARTHCHANGES - MAIN INDEX