Terry's Astronomy Thread.

[Bluearrowll]

Re: Terry's Astronomy Thread.

Daily Suspicious0bserver's Weather Post:
July 17, 2014

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

-The Big Dipper, high in the northwest after dark, is beginning to turning around to "scoop up water" through the nights of summer and early fall.

-The waning Moon, nearly at last quarter, rises around 11 or midnight and climbs high in the early-morning hours. Far in its background is Uranus, magnitude 5.8.

-The European Space Agency's Rosetta probe is now less than 10,000 km from its target: 67P/Churyumov-Gerasimenko. Rosetta is expected to reach and begin orbiting the comet's nucleus on August 6th. Long-range images suggest that the comet is a contact binary. This could present some interesting challenges for Philae, the probe's lander, which is slated to touch down on the comet's surface in early November.

A contact binary occurs when two celestial objects, such as asteroids or comets, slowly move towards each other until they are touching.
The slow approach of the two means they will form a single-oddly shaped body, rather than rebounding of one another.
Nine near-Earth objects are known to be contact binaries.
However, it is estimated that as many as 15 per cent of all near-Earth asteroids more than 650 feet (200 metres) in size are actually contact binaries.

Astro Picture of the Day:
July 17, 2014

Source:
If you're looking for something to print with that new 3D printer, try out a copy of the Homunculus Nebula. The dusty, bipolar cosmic cloud is around 1 light-year across but is slightly scaled down for printing to about 1/4 light-nanosecond or 80 millimeters. The full scale Homunculus surrounds Eta Carinae, famously unstable massive stars in a binary system embedded in the extensive Carina Nebula about 7,500 light-years distant. Between 1838 and 1845, Eta Carinae underwent the Great Eruption becoming the second brightest star in planet Earth's night sky and ejecting the Homunculus Nebula. The new 3D model of the still expanding Homunculus was created by exploring the nebula with the European Southern Observatory's VLT/X-Shooter. That instrument is capable of mapping the velocity of molecular hydrogen gas through the nebula's dust at a fine resolution. It reveals trenches, divots and protrusions, even in the dust obscured regions that face away from Earth. Eta Carinae itself still undergoes violent outbursts, a candidate to explode in a spectacular supernova in the next few million years.

[Bluearrowll]

Re: Terry's Astronomy Thread.

Daily Suspicious0bserver's Weather Post:
July 18, 2014

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

-Last-quarter Moon (exact at 10:08 p.m. Eastern Daylight Time). The Moon rises around midnight tonight, shining in Pisces.

-This week, solar activity has sharply declined. There is only one numbered sunspot on the Earth-facing side of the sun, and it is so small you might have trouble finding it. The sun today draws similarities to 2008-2009, where there were years of spotlessness when the sun plunged into the deepest solar minimum in a century. The resemblance, however, is only superficial. Deep inside the sun, the solar dynamo is still churning out knots of magnetism that should soon bob to the surface to make new sunspots. Solar Max is not finished, it's just miniature.

Until the sunspots return, solar flares are unlikely. NOAA forecasters estimate the odds of an M-flare today to be no more than 1%.

Astro Picture of the Day:
July 18, 2014

Source:
A mysterious, squid-like apparition, this nebula is very faint, but also very large in planet Earth's sky. In the mosaic image, composed with narrowband data from the 2.5 meter Isaac Newton Telescope, it spans some 2.5 full moons toward the constellation Cepheus. Recently discovered by French astro-imager Nicolas Outters, the remarkable nebula's bipolar shape and emission are consistent with it being a planetary nebula, the gaseous shroud of a dying sun-like star, but its actual distance and origin are unknown. A new investigation suggests Ou4 really lies within the emission region SH2-129 some 2,300 light-years away. Consistent with that scenario, the cosmic squid would represent a spectacular outflow of material driven by a triple system of hot, massive stars, cataloged as HR8119, seen near the center of the nebula. If so, this truly giant squid nebula would physically be nearly 50 light-years across.

[Bluearrowll]

Re: Terry's Astronomy Thread.

Daily Suspicious0bserver's Weather Post:
July 19, 2014

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

-Mars at dusk is still slightly less than 3° (two finger widths at arm's length) from Spica in the southwestern sky. But they're widening and sinking lower day by day.

-For the 4th day in a row, solar activity is extremely low. Compared to the beginning of July, when sunspots were abundant, the sun's global X-ray output has dropped by a factor of ten. Moreover, on July 17th the sunspot number fell all the way to zero. We call it "the All Quiet Event."

As July 19th unfolds, the sun is no longer completely blank. Three small sunspots are emerging, circled in this image from NASA's Solar Dynamics Observatory. These small sunspots are not about to break the quiet. None of them has the kind of complex magnetic field that harbors energy for strong flares. NOAA forecasters estimate the odds of a significant flare (M- or X-class) in the next 24 hours to be no more than 1%.

Before July 17, 2014, the previous spotless day was August 14, 2011, a gap of nearly 3 years. What happened then provides context for what is happening now. Overall, 2011 was a year of relatively high solar activity with multiple X-flares; the spotless sun was just a temporary intermission. 2014 will probably be remembered the same way. Or not. Almost anything is possible because, as one pundit observes, "you just can't predict the sun."

Astro Picture of the Day:
July 19, 2014

Source:
In this beach and skyscape from Alicante, Spain, July's Full Moon shines in the dark blue twilight, its reflection coloring the Mediterranean waters. Near the horizon, the moonlight is reddened by its long path through the atmosphere, but this Full Moon was also near perigee, the closest point to Earth along the Moon's elliptical orbit. That made it a Supermoon, a mighty 14% larger and 30% brighter than a Full Moon at apogee, the Moon's farthest orbital swing. Of course, most warm summer nights are a good time to enjoy a family meal oceanside, but what fish do you catch on the night of a Supermoon? They must be Moon breams ...

[Bluearrowll]

Re: Terry's Astronomy Thread.

Daily Suspicious0bserver's Weather Post:
July 20, 2014

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

-Solar activity is extremely low. Nevertheless, space weather continues. High above thunderstorms in the American west, red sprites are dancing across the cloudtops, reaching up to the edge of space itself. Harald Edens photographed this specimen on July 18th from the Langmuir Laboratory for Atmospheric Research in New Mexico.

"This colorful sprite occurred over a large thunderstorm system in northeast New Mexico and was visible to the naked eye," says Edens. "I took the picture using a Nikon D4s and a 50 mm f/2 lens at ISO 25600."

Inhabiting the upper reaches of Earth's atmosphere alongside noctilucent clouds, meteors, and some auroras, sprites are a true space weather phenomenon. Some researchers believe they are linked to cosmic rays: subatomic particles from deep space striking the top of Earth's atmosphere produce secondary electrons that, in turn, could provide the spark that triggers sprites.

Although sprites have been seen for at least a century, most scientists did not believe they existed until after 1989 when sprites were photographed by cameras onboard the space shuttle. Now "sprite chasers" regularly photograph the upward bolts from their own homes. Give it a try!

Astro Picture of the Day:
July 20, 2014

Source:
What's happened to our Sun? Nothing very unusual -- it just threw a filament. Toward the middle of 2012, a long standing solar filament suddenly erupted into space producing an energetic Coronal Mass Ejection (CME). The filament had been held up for days by the Sun's ever changing magnetic field and the timing of the eruption was unexpected. Watched closely by the Sun-orbiting Solar Dynamics Observatory, the resulting explosion shot electrons and ions into the Solar System, some of which arrived at Earth three days later and impacted Earth's magnetosphere, causing visible aurorae. Loops of plasma surrounding an active region can be seen above the erupting filament in the ultraviolet image. Over the past week the number of sunspots visible on the Sun unexpectedly dropped to zero, causing speculation that the Sun has now passed a very unusual solar maximum, the time in the Sun's 11-year cycle when it is most active.

[Bluearrowll]

Re: Terry's Astronomy Thread.

Daily Suspicious0bserver's Weather Post:
July 21, 2014

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

-As dawn begins very early early Tuesday morning the 22nd, look for Aldebaran near the waning crescent Moon in the east as shown below. Can you catch the Hyades stars before dawn gets too bright?

-The "All Quiet Event" is still underway. For the 6th day in a row, solar activity is extremely low, with weak solar wind, no flares, and a sunspot number near zero. NOAA forecasters put the odds of a significant flare today at no more than 1%.

Astro Picture of the Day:
July 21, 2014

Source:
Why does this comet's nucleus have two components? The surprising discovery that Comet 67P/Churyumov–Gerasimenko has a double nucleus came late last week as ESA's robotic interplanetary spacecraft Rosetta continued its approach toward the ancient comet's core. Speculative ideas on how the double core was created include, currently, that Comet Churyumov–Gerasimenko is actually the result of the merger of two comets, that the comet is a loose pile of rubble pulled apart by tidal forces, that ice evaporation on the comet has been asymmetric, or that the comet has undergone some sort of explosive event. Pictured above, the comet's unusual 5-km sized comet nucleus is seen rotating over the course of a few hours, with each frame taken 20-minutes apart. Better images -- and hopefully more refined theories -- are expected as Rosetta is on track to enter orbit around Comet Churyumov–Gerasimenko's nucleus early next month, and by the end of the year, if possible, land a probe on it.

[Spenner]

Re: Terry's Astronomy Thread.

Those sprites are really interesting/cool, something I really haven't heard of before. They look dazzling.

[Bluearrowll]

Re: Terry's Astronomy Thread.

Sprite's are something I would love to capture a photo of - where you are located is almost perfect too. Head on over to the northern shores of Lake Ontario when there is a severe thunderstorm on the US side of the lake, and look above the storm. The lake is sufficiently dark even though you're in the middle of a large metropolis area, and because the storm is so far away you stay dry. Here's the source article about the sprites, it's a good read: http://www.fma-research.com/Papers&p...pr-view-1.html

Daily Suspicious0bserver's Weather Post:
July 22, 2014

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

-Vega is the brightest star very high in the east. Far down to its lower right shines Altair, almost as bright. Altair is flagged by little Tarazed a finger-width above it, an orange-giant star far in Altair's background.

-Solar activity remains very low. There is only one sunspot (AR2119) on the Earth-facing side of the sun, and it has a simple magnetic field that poses no threat for strong explosions. NOAA forecasters estimate a scant 1% chance of M- or X-flares during the next 24 hours.

-Some of us have seen the midnight sun. Even more have witnessed sundogs. But have many people have seen a mashup of the two--the elusive midnight sundog? On July 21-22, Stine Bratteberg photographed the combo from Bleik, Andøya, Norway. "These fantastic sundogs appeared near midnight on the last day of the summer Midnight Sun here in northern Norway," says Bratteberg.

Sundogs, the rainbow-colored splashes of light on either side of the sun, are caused by sunlight striking ice crystals in the air. Plate-shaped crystals flutter down from the sky like leaves falling from trees. Aerodynamic forces align their flat sides parallel to the ground, and when sunlight hits a patch of well-aligned crystals at the right distance from the sun, voila!--a sundog. Bratteberg's photo also captured a faint midnight sun halo and a midnight upper tangent arc.

You can see a lot of midnight atmospheric optics from the Arctic Circle. But not for much longer. As northern summer comes to an end, the midnight sun will fade and auroras will chase the sundogs into the darkening Arctic night.

Astro Picture of the Day:
July 22, 2014

Source:
Yes, but have you ever seen aurora from a cave? To capture this fascinating juxtaposition between below and above, astrophotographer Bjargmundsson spent much of a night alone in the kilometer-long Raufarhólshellir lava cave in Iceland during late March. There, he took separate images of three parts of the cave using a strobe for illumination. He also took a deep image of the sky to capture faint aurora, and digitally combined the four images later. The 4600-year old lava tube has several skylights under which stone rubble and snow have accumulated. Oh -- the person standing on each mound -- it's the artist.

[Bluearrowll]

Re: Terry's Astronomy Thread.

Daily Suspicious0bserver's Weather Post:
July 23, 2014

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

-As dawn brightens on Thursday morning the 24th, spot Venus low in the east-northeast with the waning crescent Moon to its right and Mercury still to its lower left, as shown here.

-Today is the second anniversary of a scary near-miss. On July 23, 2012, Earth narrowly evaded a powerful solar storm capable of knocking civilization back into the 19th century. The event confirms that "solar superstorms" are real, and the odds of impact may be higher than we think: 12% in the next 10 years http://science.nasa.gov/science-news...ul_superstorm/

-Last night, a bank of noctilucent clouds (NLCs) rippled across northern Europe. "They were stunning," reports Alex Lebedev, who witnessed the apparition from Kohtla-Järve, Ida-Virumaa, Estonia. "Viewing it by eye was even better than the photo," he says.

NLCs are Earth's highest clouds. Seeded by "meteor smoke," they form at the edge of space 83 km above Earth's surface. When sunlight hits the tiny ice crystals that form around the meteor debris, the clouds glow electric blue.

July is the best month to see NLCs. They favor the climate of summer because that is when water molecules, warmed by summer sunlight, are wafted up from the lower atmosphere to mix with the meteor smoke. That is also, ironically, when the upper atmosphere is coldest, allowing the ice crystals of NLCs to form.

The natural habitat of noctilucent clouds is the Arctic Circle. In recent years, however, they have spread to lower latitudes with sightings as far south as Utah and Colorado. This will likely happen in 2014 as well.

Astro Picture of the Day:
July 23, 2014

Source:
Why does this starfield photograph resemble an impressionistic painting? The effect is created not by digital trickery but by large amounts of interstellar dust. Dust, minute globs rich in carbon and similar in size to cigarette smoke, frequently starts in the outer atmospheres of large, cool, young stars. The dust is dispersed as the star dies and grows as things stick to it in the interstellar medium. Dense dust clouds are opaque to visible light and can completely hide background stars. For less dense clouds, the capacity of dust to preferentially reflect blue starlight becomes important, effectively blooming the stars blue light out and marking the surrounding dust. Nebular gas emissions, typically brightest in red light, can combine to form areas seemingly created on an artist's canvas. Photographed above is the central part of the nebula IC 4603 surrounding the bright star SAO 184376 (actually 8th magnitude) which mostly illuminates the blue reflection nebula. IC 4603 can be seen near the very bright star Antares (1st magnitude) toward the constellation of Ophiuchus.

[Bluearrowll]

Re: Terry's Astronomy Thread.

Daily Suspicious0bserver's Weather Post:
July 24, 2014

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

-In a really dark sky, the Milky Way now forms a magnificent arch high across the whole eastern sky after darkness is complete. It runs all the way from below Cassiopeia in the north-northeast, up and across Cygnus and the Summer Triangle in the east, and down past the spout of the Sagittarius Teapot in the south.

-This week, Jupiter is passing behind the sun. Normally solar interference would make it difficult for radio astronomers to pick up Jupiter's shortwave radio bursts. Because the sun is so quiet, however, Jupiter is still able to maake itself heard. "I was able to capture distinct narrow-band radio emissions from Jupiter on July 21st," reports Thomas Ashcraft of New Mexico. They are the sloping lines in this dynamic spectrum he recorded using a RadioJove Project dual dipole antenna.

"At the time Jupiter was 6.3 Astronomical Units (585,621,586 miles) distant from Earth," he adds. "I think this is a neat observation because it means there is always the possibility of receiving Jupiter radio emissions here on Earth--even when the sun is in the way and Jupiter is very distant."

Jupiter's radio storms are caused by natural radio lasers in the planet's magnetosphere that sweep past Earth as Jupiter rotates. Electrical currents flowing between Jupiter's upper atmosphere and the volcanic moon Io can boost these emissions to power levels easily detected by ham radio antennas on Earth. Jovian "S-bursts" and "L-bursts" mimic the sounds of woodpeckers, whales, and waves crashing on the beach.

Astro Picture of the Day:
July 24, 2014

Source:
This alluring all-skyscape was taken 5,100 meters above sea level, from the Chajnantor Plateau in the Chilean Andes. Viewed through the site's rarefied atmosphere at about 50% sea level pressure, the gorgeous Milky Way stretches through the scene. Its cosmic rifts of dust, stars, and nebulae are joined by Venus, a brilliant morning star immersed in a strong band of predawn Zodiacal light. Still not completely dark even at this high altitude, the night sky's greenish cast is due to airglow emission from oxygen atoms. Around the horizon the dish antenna units of the Atacama Large Millimeter/submillimeter Array, ALMA, explore the universe at wavelengths over 1,000 times longer than visible light.

[Bluearrowll]

Re: Terry's Astronomy Thread.

Daily Suspicious0bserver's Weather Post:
July 25, 2014

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

-Mars and Spica shine in the southwest at nightfall. Mars keeps pulling farther away from Spica; they're now 6° apart. Saturn glows pale yellow to their upper left. Arcturus sparkles high to their upper right.

-In the middle of Solar Max, the sun has slipped into a state that resembles Solar Minimum. Sunspot numbers are low; the sun's X-ray and radio output are depressed; and NOAA forecasters estimate a scant 1% chance of solar flares during the next 24 hours. The quiet could be disturbed during the weekend, however, by the expected return of two old sunspots currently transiting the farside of the sun.

-The luminous tendrils of noctilucent clouds (NLCs) have been likened to "frozen lightning", slow-moving bolts of electric-blue that slowly zig-zag across the twilight sky during the months of Arctic summer. Last night photographer P-M Hedén witnessed a display over Hedesunda, Sweden, that suggested a different name: "They looked like 'veins of Heaven,'" he says. "I was really hoping for a good show like this because my children came along to watch," says Hedén. "We were not disappointed. From the beginning at 23:00 local time we saw noctilucent clouds all around the sky - amazing! Around 1 AM we had veins of Heaven both in the sky and reflected in the water."

Astro Picture of the Day:
July 25, 2014

Source:
The Crab Pulsar, a city-sized, magnetized neutron star spinning 30 times a second, lies at the center of this tantalizing wide-field image of the Crab Nebula. A spectacular picture of one of our Milky Way's supernova remnants, it combines optical survey data with X-ray data from the orbiting Chandra Observatory. The composite was created as part of a celebration of Chandra's 15 year long exploration of the high energy cosmos. Like a cosmic dynamo the pulsar powers the X-ray and optical emission from the nebula, accelerating charged particles to extreme energies to produce the jets and rings glowing in X-rays. The innermost ring structure is about a light-year across. With more mass than the Sun and the density of an atomic nucleus, the spinning pulsar is the collapsed core of the massive star that exploded, while the nebula is the expanding remnant of the star's outer layers. The supernova explosion was witnessed in the year 1054.

[Bluearrowll]

Re: Terry's Astronomy Thread.

Daily Suspicious0bserver's Weather Post:
July 26, 2014

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

-New Moon (exact at 6:42 p.m. EDT).
Summer is hardly more than a third over, astronomically speaking. But already the Great Square of Pegasus, symbol of the coming fall, heaves up from behind the east-northeast horizon at dusk and climbs higher in the east through the evening. It's balancing on one corner.

-The return of old sunspots AR2107 and AR2108 from the farside of the sun has failed to elevate solar activity. The two formerly-active regions decayed during their two week absence and are now little more than "sunspot corpses." Forecasters expect the quiet sun to remain quiet throughout the weekend.

-Auroras were *not* in the forecast this weekend. Nevertheless, "they're baaaaaaack," reports Bob Conzemius, who saw the Northern Lights on July 26th over Grand Rapids, Minnesota:

"It has been a pretty quiet summer in northern Minnesota for seeing auroras, so it was nice to see them again," says Conzemius. "I shot entirely within the city limits of Grand Rapids, starting from my front yard and ending at McKinney Lake as it was getting light at 4:00 AM CDT."

The source of this unexpected display was a fluctuation in the interplanetary magnetic field. The IMF tipped south, opening a crack in Earth's magnetospere. Solar wind poured in and ignited the auroras.

Astro Picture of the Day:
July 26, 2014

Source:
Shiny NGC 253 is one of the brightest spiral galaxies visible, and also one of the dustiest. Some call it the Silver Dollar Galaxy for its appearance in small telescopes, or just the Sculptor Galaxy for its location within the boundaries of the southern constellation Sculptor. First swept up in 1783 by mathematician and astronomer Caroline Herschel, the dusty island universe lies a mere 10 million light-years away. About 70 thousand light-years across, NGC 253 is the largest member of the Sculptor Group of Galaxies, the nearest to our own Local Group of Galaxies. In addition to its spiral dust lanes, tendrils of dust seem to be rising from a galactic disk laced with young star clusters and star forming regions in this sharp color image. The high dust content accompanies frantic star formation, earning NGC 253 the designation of a starburst galaxy. NGC 253 is also known to be a strong source of high-energy x-rays and gamma rays, likely due to massives black hole near the galaxy's center.

[Bluearrowll]

Re: Terry's Astronomy Thread.

Daily Suspicious0bserver's Weather Post:
July 27, 2014

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

-Despite an uptick in the sunspot number, solar activity remains low. AR2121 has a 'beta-gamma' magnetic field that harbors energy for M-class solar flares, but so far the quiet sunspot seems dis-inclined to erupt. A significant flare this weekend would be a surprise.

-What a difference 10 years can make. The Solar Max of 2014 has been mild, producing relatively few sunspots and meagre auroras. A decade ago, however, a much more potent Solar Max was underway. A strong solar storm on July 27, 2004, sparked Northern Lights as far south as the Anza-Borrego Desert of California. Photographer Dennis Mammana recalls the night: "It was ten years ago--during the pre-dawn hours of July 27, 2004--that the Anza-Borrego Desert of Southern California was bathed in the most unusual of light—that of the aurora borealis. On this morning it danced over so wide an area of the northern sky that it required four wide-angle images stitched carefully together to capture it all."

"As the sky darkened the night before, solar data convinced me that we in the Desert Southwest might get a rare display of Northern Lights, so I aimed a camera north and set it to take one exposure every minute. From time to time I checked the camera's LCD screen to see if it had captured anything of interest. Then, just before 4 a.m., I discovered blue streaks across the image. 'What a lousy time for the sensor to crap out on me!', I thought. But as I scrolled through the previous images to learn where it went bad, I saw the blue streaks dancing gracefully across the scene. It was the Northern Lights!"

"I hastily threw all my gear in the back of the Jeep and headed for an interesting foreground a couple of miles away. And the photo you see is the result--perhaps the only image of the northern lights with ocotillos in the foreground!"

Mammana's recollection reminds us what a "good Solar Max" is really like. There is still hope, however, that the ongoing mini-Max might produce some good displays. Statistics of previous solar cycles show that the strongest geomagnetic storms tend to occur during the declining phase of solar cycles--in other words, just where we are now. There may yet be SoCal auroras in the offing before this Solar Max is done.

Astro Picture of the Day:
July 27, 2014

Source:
The clouds surrounding the star system Rho Ophiuchi compose one of the closest star forming regions. Rho Ophiuchi itself is a binary star system visible in the light-colored region on the image right. The star system, located only 400 light years away, is distinguished by its colorful surroundings, which include a red emission nebula and numerous light and dark brown dust lanes. Near the upper right of the Rho Ophiuchi molecular cloud system is the yellow star Antares, while a distant but coincidently-superposed globular cluster of stars, M4, is visible between Antares and the red emission nebula. Near the image bottom lies IC 4592, the Blue Horsehead nebula. The blue glow that surrounds the Blue Horsehead's eye -- and other stars around the image -- is a reflection nebula composed of fine dust. On the above image left is a geometrically angled reflection nebula cataloged as Sharpless 1. Here, the bright star near the dust vortex creates the light of surrounding reflection nebula. Although most of these features are visible through a small telescope pointed toward the constellations of Ophiuchus, Scorpius, and Sagittarius, the only way to see the intricate details of the dust swirls, as featured above, is to use a long exposure camera.

[Bluearrowll]

Re: Terry's Astronomy Thread.

Daily Suspicious0bserver's Weather Post:
July 28, 2014

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

-Mars continues its eastward trek against the cosmic backdrop. Look southwest at dusk. You'll notice that it's now definitely closer to Saturn than Antares is. Mars is to Saturn's lower right; Antares is to Saturn's lower left.

-NOAA forecasters estimate a 20% chance of polar geomagnetic storms today when Earth makes contact with a minor solar wind stream. Sky watchers around the darkening Arctic Circle should be alert for auroras.

-Earth is entering a broad stream of debris from Comet Swift-Tuttle, source of the annual Perseid meteor shower. Although the peak of the shower is not expected until August, meteors are already flitting acrosss the night sky. On July 27th, NASA cameras caught this Perseid fireball flying over New Mexico.

Over the weekend, NASA detected a total of five Perseid fireballs, a "micro-flurry" that signals the beginning of the annual display. Normally the best time to watch would be during the shower's peak: August 11th through 13th. This year, however, the supermoon will cast an interfering glare across the nights of maximum activity, reducing visibility from 120 meteors per hour (the typical Perseid peak rate) to less than 30. Instead, late July-early August might be the best time to watch as Earth plunges deeper into the debris stream before the Moon becomes full.

If you go out meteor watching in the nights ahead, you'll likely see another shower, too: the Southern Delta Aquariids. Produced by debris from Comet 96P/Machholz, this shower peaks on July 29-30 with 15 to 20 meteors per hour. This is considered to be a minor shower, but rich enough in fireballs to merit attention. NASA will stream the display from an observing site at the Marshall Space Flight Center in Alabama. Live video begins on July 29th at 9:30 pm EDT.

Astro Picture of the Day:
July 28, 2014

Source:
The clouds surrounding the star system Rho Ophiuchi compose one of the One of the most identifiable nebulae in the sky, the Horsehead Nebula in Orion, is part of a large, dark, molecular cloud. Also known as Barnard 33, the unusual shape was first discovered on a photographic plate in the late 1800s. The red glow originates from hydrogen gas predominantly behind the nebula, ionized by the nearby bright star Sigma Orionis. The darkness of the Horsehead is caused mostly by thick dust, although the lower part of the Horsehead's neck casts a shadow to the left. Streams of gas leaving the nebula are funneled by a strong magnetic field. Bright spots in the Horsehead Nebula's base are young stars just in the process of forming. Light takes about 1,500 years to reach us from the Horsehead Nebula. The above image is a digital combination of images taken in blue, green, red, and hydrogen-alpha light from the Argentina, and an image taken in infrared light by the orbiting Hubble Space Telescope.

[Bluearrowll]

Re: Terry's Astronomy Thread.

Daily Suspicious0bserver's Weather Post:
July 29, 2014

What's in the sky tonight?
July 29, 2014

-Vega is the brightest star very high in the east. Far down to its lower right shines Altair, almost as bright. Altair is flagged by little Tarazed (3rd magnitude) a finger-width above it, an orange giant far in Altair's background.

-The European Space Agency's Rosetta spacecraft is now less than 2300 km from Comet 67P/Churyumov-Gerasimenko. In only 9 days, Rosetta will reach the comet's core and go into orbit around it. Latest images from the probe's navigation camera show a strangely-shaped nucleus that is coming into sharper focus day by day.

Astro Picture of the Day:
July 29, 2014

Source:
To some, it may look like a portal into the distant universe. To others, it may appear as the eye of a giant. Given poetic license, both are correct. Pictured above is a standard fisheye view of the sky -- but with an unusual projection. The view is from a perch in New Zealand called Te Mata Peak, a name that translates from the Maori language as "Sleeping Giant". The wondrous panorama shows the band of our Milky Way Galaxy right down the center of the sky, with the Large and Small Magellanic Clouds visible to the right. The red hue is atmospheric airglow that surprised the photographer as it was better captured by the camera than the eye. The above image was taken two weeks ago as the photographer's sister, on the left, and an acquaintance peered into the sky portal.

[MinaciousGrace]

Re: Terry's Astronomy Thread.

cosmic asscrack detected