GEOMAGNETIC STORMS POSSIBLE THIS WEEK: NOAA forecasters estimate a 60% chance of G1-class geomagnetic storms late on May 17th when a stream of solar wind hits Earth's magnetic field. The gaseous material is flowing from a southern hole in the sun's atmosphere. High-latitude sky watchers should be alert for auroras and, of course, STEVE. Free: Aurora Alerts.
WHAT THE NEW MOON REALLY LOOKS LIKE: The New Moon is supposed to be entirely black, right? Wrong. Astrophotographer Thierry Legault photographed yesterday's New Moon over Normandy, France, and he found an exquisitely-thin crescent of light:
"I went to Normandy to find the clear sky I needed to photograph this crescent at the exact moment of the New Moon (May 15th at 11:48 UTC)," says Legault. "This is the youngest possible crescent, the age of the Moon at this instant being exactly zero. The irregularities and discontinuities in the crescent are real; they are caused by mountains and craters at the edge of the lunar disk."
The Moon was only 5 degrees from the sun in broad daylight when Legault took the picture. "At this very small separation, the crescent is extremely thin (a few arc seconds at maximum) and, above all, it is drowned in the solar glare, the blue sky being about 1000 times brighter than the crescent itself. In order to reduce the glare, I used an infrared filter and a pierced screen in front of the telescope to prevent stray sunlight from entering." he explains.
Seeing this image for the first time, most people wonder Has anyone ever done this before? The answer is "yes." Thierry Legault himself did it in 2010 and 2013. For some astrophotographers, the incredible is routine. Congratulations, Theirry, on another great capture.
Note: The reason the New Moon isn't always black is that the Moon's orbit around Earth is tilted with respect to the Moon's orbit around the sun. Occasionally, this allows the New Moon to be as far from the sun as 5 degrees, with a crescent to show for it.
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LOST ASTEROID BUZZES STAR CLUSTER: Last night, asteroid 2010 WC9 flew past Earth. But first, it flew past a star cluster. "On the evening of 15th May 2018 (AEST) 2010 WC9 glided past the magnificent Globular Cluster Messier 10 (M10) on its way to making its closest approach to our planet," says Dennis Simmons who photographed the encounter from Brisbane, Australia:
"The 'wobbly' appearance of the trail is not caused by the asteroid tumbling," he notes. "Those slight wiggles are a result of periodic errors in my telescope mount's gear train."
The asteroid briefly worried Simmons when it did not show up on time. "I had my optics trained on the star cluster, but the recalcitrant asteroid stubbornly refused to make an appearance. I quickly ran upstairs and checked the schedule on my desktop PC; it agreed with my notebook at the telescope. So, I decided to keep recording and sure enough, 2010 WC9 entered from stage left. I was thrilled to have picked it up, at mag +12. It was some 5 minutes late…"
2010 WC9 is known as the "lost asteroid" because astronomers lost track of it soon after it was discovered in November 2010. The asteroid receded from Earth and didn't return for nearly 8 years--until this week.
Estimates of 2010 WC9's size range from 60 m to 130 m wide. This puts it in the class of the Tunguska impactor, which leveled a forest in Siberia in 1908. And it is at least 3 times as large as the Chelyabinsk meteoroid, which exploded in the morning sky over Russia on Feb. 15, 2013, shattering windows and knocking people to the ground. There's no danger of a collision with 2010 WC9, though. New observations of the asteroid in recent days have extended our knowledge of its orbit and eliminated it as a threat for at least the next 100 years.
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3D GLOWING MOON GLOBE: Are you looking for a far-out gift? Consider this: In January, the students of Earth to Sky Calculus flew a glowing 3D printed Moon globe to the stratosphere:
You can have it for $149.95. The students are selling these unique globes as a fundraiser for their cosmic ray monitoring program.
The surface of the sphere is an accurate topo-map of lunar terrain, tracing every major crater and mountain range. It is also a night light. A built-in USB-rechargeable battery provides up to 20 hours of illumination.
Each glowing orb comes with a greeting card showing the Moon in flight and telling the story of its journey to the edge of space. All proceeds support Earth to Sky Calculus and hands-on STEM research.
Far Out Gifts: Earth to Sky Store
All proceeds support hands-on STEM education
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