FIRST AURORA LISTENING POST ESTABLISHED: For centuries Arctic sky watchers have occasionally reported hearing sounds under the Northern Lights--from "blaster fire" to "geomagnetic thunder". It's a controversial topic, with some researchers asserting that the sounds are imaginary. To place the field on a firm scientific footing, Prof. Unto Laine of Finland's Aalto University is setting up a dedicated listening post at the Hankasalmi observatory in Northern Finland. Sensitive microphones will listen for auroral sounds alongside an aurora webcam, a magnetometer, and other sensors, generating as much as 32GB of data every night. Such an acoustic observatory might finally crack the mystery of auroral sounds. Free: Aurora Alerts.
COMING SOON, THE COMET OF THE YEAR: Astronomers are calling Comet 46P/Wirtanen the "comet of the year." Two months from now, on Dec. 16th, the kilometer-wide ball of dirty ice will come within 11.5 million km of Earth--making it one of the 10 closest-approaching comets of the Space Age. Comet 46P/Wirtanen will probably become a naked eye object for several weeks during the holidays. Here's what it looks like now:
Yasushi Aoshima of Ishikawa, Japan, took the picture using a 12-inch telescope. It shows the comet's green atmosphere which is, impressively, almost twice as wide as the planet Jupiter. The green color comes from diatomic carbon (C2)--a gaseous substance common in comet atmospheres that glows green in the near-vacuum of space.
At the moment, the integrated brightness of the comet is similar to a 10th magnitude star--that is, dim. However, forecasters expect it to brighten more than 200-fold by December. If current trends hold, 46P could ultimately reach magnitude +3, making it not a Great Comet but a very good one, visible to the unaided eye and an easy target for binoculars or small telescopes.
Comet Wirtanen passes through the inner solar system every 5.4 years. Right now it is near the orbit of Mars, and it is heading in our direction. Click on the image above to explore the comet's approach, courtesy of NASA/JPL.
Are you new to comet photography? Get Astro-imaging Tutorials from award-winning astrophotographer Damian Peach.
More resources: sky map; ephemeris; 3D orbit; light curve.
SOLAR SYSTEM CRYSTAL BALL: The holidays are coming. To get ready for gift-giving, the students of Earth to Sky Calculus launched a Solar System crystal ball to the stratosphere. Watch the video as the orb travels onboard a giant helium balloon 93,000 feet above Earth's surface, stretching, focusing, and inverting the incredible landscape of the Sierra Nevada mountains behind it:
You can have it for $229. The students are selling these crystal balls to raise funds for their cosmic ray ballooning program. The 800 gram sphere contains an embedded model of the Solar System, including the sun, eight planets and their moons. It makes an incredible gift for anyone interested in space.
Each crystal ball comes with a unique gift card showing the item at the edge of space and telling the story of its flight. All proceeds support Earth to Sky Calculus and hands-on STEM research.
Far Out Gifts: Earth to Sky Store
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