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Radiant point for December’s Geminid meteor shower

Where do you look to see December’s famous Geminid meteor shower? Simply look in an open sky, in no particular direction. That’s because these meteors fly in many different directions and in front of numerous age-old constellations. But meteor showers do have radiant points. That is, if you trace the paths of the Geminid meteors backward, they all appear to radiate from a point in the constellation Gemini the Twins. Do you need to find Gemini to watch the shower? No, but it’s fun to spot the radiant point in the night sky. Follow the links inside to learn more about the Geminid shower, and its radiant point.

Incredible video of dense fog over Dallas

What happens when it’s so foggy outside, you can’t see anything? Simple. You grab a drone, fly it into the air and use it to capture some amazing video. Mike Prendergast posted an aerial view on top of today’s dense fog – December 9, 2014 – in Dallas, Texas. The footage is incredible. Check it out above!

Video: Chasing Starlight

Longtime EarthSky friend Jack Fusco dropped us a note earlier today. He wrote of his newest time-lapse video, which he has titled Chasing Starlight. It explores the dark skies of Banff and Jasper National Parks in Alberta, Canada.

How to spot the International Space Station

ISS crossing the sky in a long-exposure photograph by Antonín Hušek?.

ISS crossing the sky in a long-exposure photograph by Antonín Hušek?.

Every so often, the International Space Station (ISS) becomes visible in your night sky. It’ll look like a bright star moving quickly above the horizon. The ISS is so bright, it can even been seen from the center of a city. Here’s how you can spot the ISS in your night sky.

Killing rats to save birds as glaciers recede

To commemorate the rat eradication campaign, South Georgia issued a set of stamps, pictured here.

To commemorate the rat eradication campaign, South Georgia issued a set of stamps, pictured here.

Glacier melt means rats can reach bird nests on South Georgia, an island north of Antarctica and east of the Falklands. What to do? Send in helicopters!

As Dawn approaches, new image of dwarf planet Ceres

Dwarf planet Ceres as captured by Dawn spacecraft on December 1, 2014.  Dawn will arrive at Ceres in March, 2015.

Dwarf planet Ceres, largest object in asteroid belt, seen by Dawn spacecraft on December 1. A smaller, correctly exposed image has been enlarged. Resolution 108 kilometers. Image via NASA / JPL DAWN spacecraft.

Here, the 976-kilometer-wide / 606-mile-wide main belt asteroid / protoplanet / dwarf planet 1 Ceres is seen by the approaching Dawn spacecraft from a distance of 1.2 million kilometers / 745,000 miles, on December 1, 2014. Dawn begins its approach phase toward Ceres on December 26 and will arrive at Ceres in March, 2015.

Dawn Journal: Update on trek from Vesta to Ceres

Illustration of the relative locations (but not sizes) of Earth, the sun, and Dawn in early December 2014. (Earth and the sun are at that location every December.) The images are superimposed on the trajectory for the entire mission, showing the positions of Earth, Mars, Vesta, and Ceres at milestones during Dawn’s voyage. Credit: NASA/JPL

Illustration of the relative locations (but not sizes) of Earth, the sun, and Dawn in early December 2014. Images are superimposed on the trajectory for the entire mission, showing the positions of Earth, Mars, Vesta, and Ceres at milestones during Dawn’s voyage. Credit: NASA/JPL

Flying silently and smoothly through the main asteroid belt between Mars and Jupiter, the Dawn spacecraft emits a blue-green beam of high velocity xenon ions. On the opposite side of the sun from Earth, firing its uniquely efficient ion propulsion system, the distant adventurer is continuing to make good progress on its long trek from the giant protoplanet Vesta to dwarf planet Ceres. Let’s look ahead to some upcoming activities …

Why scientists want to find a pulsar orbiting a black hole

View larger. | Via Skascience

Artist’s concept of black hole via SKA Organization/Swinburne Astronomy Productions

Pulsars are the most precise “clocks” in the known universe. They emit signals with such clocklike regularity that scientists use them in tests of Einstein’s general theory of relativity, which explains how gravity works. These tests of relativity work best in star systems where pulsars orbit with other pulsars or with white dwarfs. But what scientists really wish to find – in order to carry their tests of Einstein’s theory of gravity to the highest possible level of precision – is a pulsar orbiting a black hole. And that, my friends, is very, very rare.

How galaxies evolve in the cosmic web

Galaxies are distributed along a cosmic web in the universe. “Mpc/h” is a unit of galactic distance (1 Mpc/h is more than 3.2 million light-years). Image credit: Volker Springel, Virgo Consortium.

Artist’s illustration of the “cosmic web.” The web walls are galaxies in clusters. Filaments are woven throughout, like threads. Mpc/h is a unit of distance, with 1 Mpc/h more than 3.2 million light-years. Image via Volker Springel, Virgo Consortium.

An international team of researchers applied a new computational method to existing data on the large-scale structure of the universe, or “cosmic web.” Their work indicates that the filaments that bridge the denser regions of the web have a much higher chance of actively forming stars. In other words, in the distant universe, galaxy evolution seems to have been accelerated in the filaments.

Glacier melt rate in West Antarctica tripled in last decade

View larger. | Antarctic glaciers, via the American Geophysical Union.

View larger. | Glaciers in West Antarctica as seen during a NASA Operation IceBridge campaign on October 29, 2014. Photo via NASA/Michael Studinger and via AGU.

The melt rate of glaciers in the fastest-melting region of Antarctica has tripled during the last decade, according to a comprehensive, 21-year analysis that reconciles four different techniques previously used to measure Antarctic ice melting.