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Water abundant in first billion years after Big Bang?

This Hubble image features dark knots of gas and dust known as

This Hubble image features dark knots of gas and dust known as “Bok globules,” which are dense pockets in larger molecular clouds. Similar islands of material in the early universe could have held as much water vapor as we find in our galaxy today, despite containing a thousand times less oxygen. Image credit: NASA, ESA, and The Hubble Heritage Team

Water vapor could have been just as abundant in pockets of space a billion years after the Big Bang as it is today, suggest new research.

May 2015 guide to the five visible planets

Skywatcher, by Predrag Agatonovic.

Skywatcher, by Predrag Agatonovic.

Four planets are visible at nightfall this month: Mercury, Venus, Jupiter and Saturn. Mars disappears into the glare of sunset.

Man sings “If I only had a brain” during MRI

While he sings, watch what’s going on inside his head.

Why do we celebrate May Day?

Happy May Day!

May Day is an ancient spring festival in the Northern Hemisphere. It’s an astronomical holiday, one of the year’s four cross-quarter days, or day that falls more or less midway between an equinox and solstice.

What’s the birthstone for May?

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Happy birthday to all you May babies! Your birthstone, the emerald, is a type of beryl colored green by chromium. Perfect emeralds are among the rarest of gemstones.

Best evening apparition of Mercury for Northern Hemisphere

Draw an imaginary line from Jupiter and past Venus to locate Mercury near the horizon. The planets are always found near the ecliptic - Earth's orbital plane projected onto the constellations of the Zodiac.

Draw an imaginary line from Jupiter and past Venus to locate Mercury.

For the Northern Hemisphere, the planet Mercury is now just starting its best evening apparition of 2015. It’ll be visible for the first half of May – maybe the first three weeks. Have binoculars? If so, take a look at the Pleiades star cluster coupling up with Mercury within the same binocular field of view as dusk ebbs into darkness. At mid-northern latitudes, Mercury sets a whopping 110 minutes or so after the sun.

MESSENGER ends mission, crashes into Mercury

Predicted ground approach track of MESSENGER's Mercury impact on April 30, 2015.

Predicted ground approach track of MESSENGER’s Mercury impact on April 30, 2015.

UPDATE APRIL 30 AT 4 P.M. CDT (21OO UTC): Mission controllers at the Johns Hopkins University Applied Physics Laboratory (APL) in Laurel, Maryland, have confirmed NASA’s MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft impacted the surface of Mercury, as anticipated, at 3:26 p.m. EDT.

MESSENGER’s final image from Mercury

The image is located within the floor of the 93-kilometer-diameter crater Jokai. The spacecraft struck the planet just north of Shakespeare basin.

Final image from Mercury, from the MESSENGER spacecraft, shortly before impact.

Here is the final image acquired and transmitted back to Earth by the MESSENGER spacecraft on April 30, 2015, shortly before it struck the planet. MESSENGER spent over four years orbiting Mercury. The image is located within the floor of the 93-kilometer-diameter crater Jokai. The spacecraft struck the planet just north of Shakespeare basin.

Who loves rainbows?

Merida, Spain. April 26, 2015. Photo:  Juan Manuel  Pérez Rayego

Merida, Spain. April 26, 2015. Photo: Juan Manuel Pérez Rayego

April showers brought these rainbows. Enjoy these awesome photos from our friends!

Mercury and the Pleiades

View larger. | Mercury and the Pleiades on April 29, 2015 by Jack Webb.

Mercury is just above the ridge in this photo, and the Pleiades is the little dipper-shaped star cluster above Mercury. Photo by Jack Webb.

Jack Webb in Wapiti, Wyoming captured this shot last night of Mercury and the Pleiades, a tiny dipper-shaped star cluster also called the Seven Sisters. Congratulations, Jack! The elusive planet Mercury and the lovely Seven Sisters are low in the west after sunset now. Watch for them.