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Celebrate Earth Day 2015 with NASA

Image credit: NASA

Image credit: NASA

Share pics and video of your favorite places on Earth to social media with hashtag #NoPlaceLikeHome. Check in to see what people around the world are sharing.

Photos: Moon and Venus April 20, 2015

Venus and the moon over a medieval castle in Turin, Italy from our friend Stefano De Rosa.  Thank you, Stefano!

April 20 Venus and moon over a medieval castle in Turin, Italy from our friend Stefano De Rosa. Thank you, Stefano!

The moon has just returned to the western sky after sunset, and it’s passing near the brightest planet, Venus. Watch for it!

Asteroid just missed Earth on Tuesday

The Virtual Telescope Project acquired this image on Monday evening, April 20, 2015.

The Virtual Telescope Project acquired this image on Monday evening, April 20, 2015.

On Tuesday morning according to U.S. clocks – at approximately 3 a.m. CDT, or 8 UTC – a small and very faint asteroid passed just 0.2 lunar distances or 45,600 miles (73,400 km) above Earth’s surface. That’s about twice as far as geostationary satellites. The Mt. Lemmon Survey, based in Tucson, Arizona, first saw this asteroid two days ago, on April 18.

Moon and Venus early evening, Lyrids before dawn

If you miss the young moon on April 19, try again as the waxing crescent moon swings close to the Pleiades cluster on April 20, and the star Aldebaran on April 21. Fortunately, the moon will set early, leaving dark skies for the April 2015 Lyrid meteor shower. The green line depicts the ecliptic.

Watch for the moon and Venus on the night of April 21. The bright star nearby is Aldebaran in the constellation Taurus the Bull.

Tonight – April 21, 2015 – look westward as darkness falls for the beautiful waxing crescent moon and bright planet Venus. They will dominate the western sky shortly after the sun goes down. As night passes, and Earth spins under the sky, the moon and Venus will soon follow the sun below the western horizon, leaving the sky dark for the 2015 Lyrid meteor shower. Follow the links inside to learn more.

Ceres’ bright spots back in view

The bright feature called

The bright double feature called Spot 5 by scientists – actually two bright spots close together – rotates into view at right in the last few frames of this animation, created from images acquired by the Dawn spacecraft on April 14 and 15.

Dawn spacecraft has reacquired images of Spot 5, the mysterious bright double feature on the dwarf planet Ceres. The bright spots look … as strange as ever.

From fins to legs to fins again

Photo credit: Tony Grover/Flickr

Photo credit: Tony Grover/Flickr

Whales, dolphins, seals and sea turtles are members of an exceptional group of animals, called marine tetrapods, that have moved from the sea to the land and back to the sea again over the last 350 million years — each time making radical changes to their life style, body shape, physiology and sensory systems.

What made these animals return to the ocean? Neil Kelley is a researcher at the Smithsonian National Museum of Natural History’s department of paleobiology. Kelley said:

They followed their stomachs into the ocean.

What is earthshine?

The moon and Venus over  North Carolina by Ken Christison.

The moon and Venus over North Carolina by Ken Christison.

That glow over the unlit part of a crescent moon – called earthshine – is light reflected from Earth.

Beautiful photos in this post!

Ocean acidification drove Earth’s largest mass extinction

Computer artwork via the BBC

Computer artwork via the BBC

During the Permian–Triassic mass extinction event 252 million years ago, most life on Earth perished. Scientists have now obtained evidence that ocean acidification played a key role in the die-off.

Start watching for Lyrid meteors

Composite image of Lyrid and no-Lyrid meteors over New Mexico from April 21-23, 2012. Image via NASA/MSFC/Danielle Moser.

The Lyrid meteor shower is active each year from about April 16-25, and we’re now approaching the peak of this shower. The peak night for the Lyrid meteor shower will probably fall on the mornings of April 22 and 23. This modest shower often offers no more than 10 to 20 meteors per hour at its peak, but it has been known to have bursts of activity that could dazzle you. Fortunately, the waxing crescent moon will be setting at early evening, guaranteeing a dark sky for meteor watching. Watch from late night until dawn.

Celebrate 25 years of Hubble Space Telescope

The Horsehead Nebula, photographed in 2013 celebration of the 23rd anniversary of the launch of Hubble aboard the space shuttle Discovery.

The Horsehead Nebula, photographed in 2013 in celebration of the 23rd anniversary of the launch of Hubble aboard the space shuttle Discovery. Image Credit: NASA and The Hubble Heritage Team (STScI/AURA)

On April 24, 1990, the space shuttle Discovery lifted off from Earth with the Hubble Space Telescope aboard. The following day:

… Hubble was released into space, ready to peer into the vast unknown. Since then, Hubble has reinvigorated and reshaped our perception of the cosmos and uncovered a universe where almost anything seems possible within the laws of physics.

The quote above is from a NASA website where the agency explains its plans to celebrate Hubble’s 25th anniversary. The celebration begins on April 20, 2015 and runs through April 26. There are a lot of activities mentioned – plus links to more information – inside.