URSID METEOR SHOWER: Earth is approaching the debris zone of Comet 8P/Tuttle, source of the annual Ursid meteor shower. Normally, crossing Tuttle's debris zone produces no more than 5 or 10 meteors per hour from a radiant near the North Star. This year, however, an outburst of Ursids is possible. Peter Jenniskens of NASA notes that Earth might cross a meteoroid filament on Dec. 22nd between 19h and 22h UT, multiplying the usual rates. Free: Meteor Alerts.
NEW HORIZONS CLEARED FOR ULTIMA THULE FLYBY: With no apparent hazards in its way, NASA's New Horizons spacecraft has been given a "go" to fly by Ultima Thule on Jan. 1st three times closer than it buzzed Pluto in 2015. For the past three weeks, mission controllers have been using the spacecraft's Long Range Reconnaissance Imager (LORRI) to look for potential hazards around Ultima Thule. No rings, moons or other debris particles have been found, prompting the go ahead.
In the LORRI image, above, Ultima Thule is the bright yellow spot in the middle. Concentric circles trace two possible flyby distances. Encouraged by the absence of hazards, mission controllers have decided to fly along the closer path marked by an X. This image combines hundreds of photos taken by LORRI between August and mid-December. Faint circles radiating away from the target point are an artifact of image processing caused by the removal of background stars.
Any ring structure reflecting even just five 10-millionths of the sunlight falling on it would have been visible in the images, as would any moons more than about two miles (three kilometers) across, but the team saw none. Scientists will continue to look for rings or moons that are very close to Ultima, but those would not pose a risk.
New Horizons will make its historic close approach to Ultima Thule at 12:33 a.m. EST on Jan. 1 — the first ever flyby of a Kuiper Belt object.
"The spacecraft is now targeted for the optimal flyby," says New Horizons Principal Investigator Alan Stern . "Ultima, here we come!"
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BUY A TICKET TO THE EDGE OF SPACE: Need a last-minute Christmas gift? Consider this: For the holiday season only, we're reducing the cost of payload space on Earth to Sky Calculus balloons from $500 to only $299.95. Buy an edge of space gift certificate before Dec. 25th and you can send an experiment, photo, or keepsake item to the stratosphere, completely supported by an Earth to Sky Calculus launch and recovery team.
This is not only a great Christmas gift, but also a good kickstarter for science fair projects. Experiments will be flown and returned along with video footage, GPS tracking, temperature, pressure, altimetry and radiation data.
To take advantage of the discounted rate, payment must be received before Dec. 25th. However, the flight can take place at any time in the next 12 months. You'll receive the ticket electronically so you can print it out and give it as a Christmas Day gift.
Far Out Gifts: Earth to Sky Store
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