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In this artist's conception, the atmosphere of an Earth-like planet displays a brownish haze - the result of widespread pollution. New research shows that the upcoming James Webb Space Telescope potentially could detect certain pollutants, specifically CFCs, in the atmospheres of Earth-sized planets orbiting white dwarf stars. Image credit: Christine Pulliam (CfA)
Science Wire | Jul 24, 2014

Can we find aliens by looking for their pollution?

Maybe some extra-terrestrials pollute their planets too.

Perseid meteor
Tonight | Jul 24, 2014

Everything you need to know: Perseid meteor shower

In the N. Hemisphere, the annual August Perseid meteor shower ranks as the year’s favorite shower. A big, bright supermoon interferes in 2014. So start observing the Perseids soon!

July 24 moon and Venus by Brenda Steffes
Photos | Jul 24, 2014

Beauty! Best photos of July 24 moon and Venus

The sky’s two brightest nighttime objects, in the east before dawn this morning.

Image Credit: NASA, ESA et al.
FAQs | Jul 23, 2014

Will the Andromeda galaxy someday collide with our Milky Way?

The Andromeda galaxy is approaching our Milky Way galaxy across the vastness of space. When will they collide?

Science Wire | Jul 22, 2014

Camelopardalids: Just a few centuries late in catching a good show

Remember the Camelopardalids, the meteor shower earlier this year astronomers said would be spectacular … except it wasn’t? Now, the same astronomers explain why.

Artist's concept of Rosetta spacecraft
Blogs | Jul 22, 2014

What to expect as Rosetta spacecraft approaches its comet

This is exciting! The first-ever rendezvous/landing on a comet. What to expect in the coming weeks as Rosetta draws alongside Comet 67P/Churyumov–Gerasimenko.

Celestial software image of Earth with two moons,.
Science Wire | Jul 22, 2014

Does Earth have a second moon?

Mars has two moons, Jupiter has 67, Saturn 62, Uranus 27, Neptune 14. But our planet Earth has just one moon. Doesn’t it?

Young moon of March 31, 2014 by Ken Christison.
Tonight | Jul 22, 2014

Longest lunar month of 2014 starts on August 25

The longest lunar month of 2014 will start August 25 and end September 24. All you need to know about the varying lengths of the lunar months, here.

Artist's illustration via CfA
Science Wire | Jul 21, 2014

Transiting exoplanet with longest year yet

Most distant planets known so far orbit close to their stars and thus have a short “year.” Kepler-421b has a year about twice as long as Earth’s.

Image Credit: Arenamontanus
Science Wire | Jul 21, 2014

What exactly is twilight?

Twilight is the time of day between daylight and darkness. Astronomers, the experts on nighttime, recognize three kinds of twilight.

Image Credit: NASA
Science Wire | Jul 20, 2014

Best photos of Apollo 11 and first footsteps on moon

Today is the 45th anniversary of humanity’s historic first steps on the moon. “One small step for [a] man, one giant leap for mankind.” The story in pictures.

Via  NASA/JPL/SSI/CICLOPS / Mother Jones
This Date in Science | Jul 19, 2014

This date in science: The day Earth smiled

On July 19, 2013, the Cassini spacecraft acquired a distant image of our home world, as we Earth citizens cast our thoughts spaceward.

Science Wire | Jul 18, 2014

Is our universe a bubble?

The multiverse hypothesis – the idea that there are other universes – can be tested, scientists say.

Meteor seen during 2013 Eta Aquarid shower by Justin Ng
Tonight | Jul 17, 2014

EarthSky’s meteor shower guide for 2014

It’s time for what we in the N. Hemisphere consider our best time of year to watch meteors. Learn when and where to catch shooting stars!

View larger. | A puncture (center right) in one of the Mars rover Curiosity’s wheels. (The sequence of cutouts at lower right are deliberate and imprint ‘JPL’ in Morse code as the wheels roll across the Martian surface.)  Image via NASA/JPL-CALTECH/MSSS, Nature.
Science Wire | Jul 17, 2014

Mars Curiosity rover now crossing dangerous terrain

The car-sized rover is currently crossing a stretch of hard, rocky ground like that which previously dented and punctured its aluminum wheels.

Photo credit: NASA
This Date in Science | Jul 17, 2014

This date in science: America and Russia meet in space

On July 17, 1975, a famous first handshake between nations in space.

Science Wire | Jul 16, 2014

Three next-generation dark matter experiments get a green light

Next generation, in this case, is defined as experiments that will be at least 10 times as sensitive as the current crop of dark matter detectors.

Apollo 11 blasts off to the moon, July 16, 1969, carrying the first three humans to visit another world.
Science Wire | Jul 16, 2014

NASA re-enacted Apollo 11 launch on 45th anniversary today

What if we’d had Twitter on July 16, 1969, the day Apollo 11 launched carrying the first humans to the moon? NASA did a live-tweet reenactment today as if we had.

Via Kenneth Tanaka et. al.
Science Wire | Jul 16, 2014

Geologic map of planet Mars

USGS released this cool geologic map of Mars this week, which was prepared for NASA. What to see first? Notice impact craters, in yellow.

Science Wire | Jul 16, 2014

Astronaut’s Vine of auroras from space

Auroras are awesome to see from here on Earth. Check out the view from space! Vine posted by ISS astronaut Reid Wiseman.

Tonight | Jul 16, 2014

Draco the Dragon on July evenings

Two of the brightest stars here are Eltanin and Rastaban. Dragon’s eyes! Rrrrr! And Thuban is just … well, awesome.