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Follow the arc to star Arcturus in May

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Now is the perfect time to look outside in the evening and learn a phrase useful to sky watchers. The phrase is: follow the arc to Arcturus.

Atmospheric carbon dioxide hits record high

Smoke from smoke stack

Image credit: Shutterstock / Maxim Kulko

NOAA scientists reported today that global levels of carbon dioxide (CO2), the most prevalent heat-trapping gas in the atmosphere, have passed a significant milestone.

NOAA says in March, 2015, the global monthly average for carbon dioxide concentration surpassed 400 parts per million. That’s the first month in modern records that the entire globe broke 400 ppm, reaching levels that haven’t been seen in about 2 million years.

Traffic around Mars gets busy

This graphic depicts the relative shapes and distances from Mars for five active orbiter missions plus the planet's two natural satellites. Image credit: NASA/JPL-Caltech

This graphic depicts the relative shapes and distances from Mars for five active orbiter missions plus the planet’s two natural satellites. Image credit: NASA/JPL-Caltech

With five active spacecraft now orbiting the planet, NASA has beefed up its traffic monitoring to make sure the Mars orbiters don’t get too close to each other.

This date in science: Neil Armstrong’s close call

May 6, 1968. More than a year before he became the first human to set foot on the moon, Neil Armstrong had a narrow escape in the Lunar Landing Research Vehicle (LLRV) at Ellington Air Force Base near Houston. The LLRV had been designed to simulate a descent to the moon’s surface, and all the lunar astronauts trained in it. That day, while Armstrong was piloting, a leaking propellant caused a total failure of his flight controls …

Warm oceans triggered US Dust Bowl

A young boy covers his mouth during a dust storm on farm. Cimarron County, Oklahoma. April 1936. Image credit: Arthur Rothstein; The Library of Congress, Prints & Photographs Division

A young boy covers his mouth during a dust storm on farm. Cimarron County, Oklahoma. April 1936. Image credit: Arthur Rothstein; The Library of Congress, Prints & Photographs Division

Ocean hot spots in the Atlantic and Pacific were drivers of the hottest summers on record for the central U.S. in 1934 and 1936, suggest new study.

X2 solar flare on May 5

The May 5 X2 flare released a coronal mass ejection - CME - a cloud of charged particles traveling faster than 1100 km/s (2.5 million mph).  CMEs like this one can affect satellites in orbit, and earthly communications, but this one does not appear to be heading in Earth's direction.   Image via Spaceweather.com

The May 5 X2 flare released a coronal mass ejection – CME – a cloud of charged particles traveling faster than 1100 km/s (2.5 million mph). CMEs like this one can affect satellites in orbit, and earthly communications, but this one does not appear to be heading in Earth’s direction. Image via NASA SDO

An X2-class solar flare erupted on May 5, 2015 at at 22:05 UTC (5:05 p.m. CDT) and ended at 22:15 UTC. The flare created a pulse of UV radiation and X-rays that caused a strong radio blackout over the Pacific. It also caused a short-lived radio burst, heard as static on shortwave receivers.

Nugget Point in New Zealand

Nugget Point by Landscapes~Rob Dickinson of Christchurch, New Zealand.

Nugget Point by Landscapes~Rob Dickinson of Christchurch, New Zealand.

“Sometimes you know you are in the right place at the right time. That you are doing what you are meant to be doing. That it all comes together and your heart sings.”

Mercury farthest east of sunset May 6

Draw an imaginary line from Jupiter and past Venus to locate Mercury near the horizon. The green line depicts the ecliptic - Earth's orbital plane projected onto the dome of sky.

Draw an imaginary line from Jupiter and past Venus to locate Mercury near the horizon. Look as soon as the sky darkens, after sunset.

Mercury, the solar system’s innermost planet, orbits the sun inside of Earth’s orbit. Therefore, Mercury always stays close to the sun in Earth’s sky and is often lost in the sun’s glare. But Mercury reaches its greatest elongation – greatest angular distance – east of the sun on May 6 (or May 7, depending on time zone), so this world can now be spotted in the west-northeast as dusk ebbs into darkness. As always, binoculars help out with any Mercury quest.

Star of the week: Thuban, a former Pole Star

The Great Pyramid of Giza contains passageways that are aligned with various stars as they appeared in the sky when Thuban was the Pole Star. Image by Nina Aldin Thune in 2005 via Wikimedia Commons.

Thuban is not a particularly bright star, but it’s special for having been a Pole Star some 5,000 years ago, around the time the Egyptian pyramids were being built. Follow the links inside to learn more about Thuban, a star that holds a special place in the hearts of stargazers.

Lunar Reconnaissance Orbiter drops nearer moon

The image is a visualization of the LRO spacecraft as it passes low over the moon¹s surface near the lunar South Pole. From this vantage point LRO will continue to make detailed measurements of the lunar surface, and now from its lower orbit near the South Pole will make unique observations of selected areas. Credits: NASA/GSFC/SVS

Artist’s concept of NASA’s Lunar Reconnaissance Orbiter, passing low over the moon’s surface near the lunar South Pole. Image via NASA/GSFC/SVS.

NASA announced today (May 5, 2015) that its Lunar Reconnaissance Orbiter (LRO) – launched from Earth in 2009 – has completed a maneuver that lowered the spacecraft’s orbit to within 12 miles (20 km) above areas near the lunar South Pole. This is the closest the spacecraft has been to the lunar surface.