The moon seems to be frequently in the news lately. In August, NASA launched the Lunar Atmosphere and Dust Environment Explorer (LADEE) from the Virginia coast. As the name suggests, LADEE’s mission is sniffing out thin clouds of dust and searching for the tenuous lunar atmosphere from lunar orbit.
It turns out that during the Apollo missions, some astronauts observed something both interesting and unexpected. From lunar orbit, they sketched glowing patches over the moon in the direction of the sun when it was just below the horizon. Thus, the moon may actually possess an exceptionally thin atmosphere consisting of dust and perhaps some gas. LADEE’s extremely sensitive instruments are designed to detect it.
Then late last year, just as LADEE was getting settled in around the moon, China launched its unmanned Chang’e 3 moon lander, named after a Chinese moon goddess. This alarmed scientists, who feared the contamination spread by Chang’e 3 would interfere with LADEE. Space.com quoted Jeff Plescia, a space scientist at The Johns Hopkins University Applied Physics Laboratory in Maryland:
“The arrival of the Chang’e 3 spacecraft into lunar orbit and then its descent to the surface will result in a significant contamination of the lunar exosphere by the propellant.”
Another view is that the controlled release of gases from Chang’e 3 would offer an opportunity to track the spread of those gases around the moon — a cosmic instance of turning lemons into lemonade.
The pro or con contamination news wasn’t very widespread. Instead, the big news was Chang’e 3’s lunar rover Yutu, named after a mythical Chinese jade rabbit. The rover was designed to survive for three months. Apparently, Yutu has suffered a mechanical breakdown.
According to Space.com, though Yutu “can now receive signals normally,” the rover hasn’t budged an inch since January. Designed to travel around a 1.2-square-mile region, Yutu appears to have moved a few dozen yards since rolling off the lander in December.
China is the third country to land a rover on the moon, with Yutu arriving more than 40 years after all the others. How good was the old technology of the previous century? The Soviet Union’s unmanned Lunokhod 1 and 2 rovers drove a combined total distance of 29.5 miles on the lunar surface. Although the U.S. has never landed an unmanned rover on the moon, it did manage to land three manned rovers carried aboard Apollos 15, 16 and 17 that transported a total of six astronauts a combined distance of 51.6 miles.
The real realm of the rovers so far in the 21st century has been the planet Mars. A total of four rovers have landed since 1997, all of which were sent by the U.S. Their names are Sojourner, Spirit, Opportunity and Curiosity. Even after ten years of operation, Opportunity is still going strong, having traveled more than 24 miles to date. Curiosity, the latest rover, landed in 2012.
There are more ambitious plans for Mars in the future. In February Congress held a hearing to consider sending a manned mission aboard the Orion Crew Exploration Vehicle (CEV) on a flyby mission to Venus and Mars as early as 2021. Orion is the next generation of U.S. spacecraft and is designed for interplanetary exploration. No manned spacecraft has left earth orbit since Apollo 17 in 1972.
Speaking of Mars, it is starting to be well placed for viewing. It may be found low in the east-southeast sky at 11 p.m. To its right you’ll also see the bright star Spica in the constellation Virgo. The angular distance between Mars and Spica is less than the width of your outstretched fist. Mars is brighter and has a distinct orange hue. Both are easily visible to the unaided eye.
In a telescope Mars is best viewed at its highest point in the sky, or between 2 and 3 a.m. Mars reaches opposition April 8 and will be visible all night long. Its small disk should be visible in a telescope. How small? Mars’ angular size will only be 15 arcseconds, or less than one percent the width of the full moon.
Also, don’t miss the March 9 debut of the new 13-part Fox documentary, “Cosmos.” The original “Cosmos,” a landmark series, premiered in 1980.