China’s Chang’e 3 Camera Still Snapping Photos From The Moon

The Yutu rover captured this photo on January 14, 2014 as it approached to within 3 meters of a large rock southwest of the lander. Dragon Rock is about 1.5 meters tall.
The Chinese Yutu rover took this photo on January 14, 2014 as it wheeled within 10 feet (3 meters) of “Dragon Rock” southwest of the lander. The rock stands about 5 feet (1.5-m) high. Credit: CNSA

Remember the Chinese Chang’e 3 mission to the moon in December 2013? Once alighting on the dusty surface on December 14, the golf cart-sized Yutu rover wheeled down the lander’s ramp to photograph the landscape, measure the soil composition and probe the lunar crust with ground-penetrating radar. Everything went well until a mechanical malfunction stopped the rover in its tracks about a month later and prevented its solar cell panels from closing to keep the rover’s interior insulated from the extreme cold of the long lunar night. Despite these obstacles, Yutu’s instruments kept plugging away for a year until radio transmissions ceased this past winter.


Watch the dramatic landing of Chang’e 3 in HD

Meanwhile, one of the primary instruments on the lander, a camera that can take pictures of the sky in ultraviolet light, is still cranking out photos to this day. Called the Lunar-based ultraviolet telescope or LUT, its optics are specialized for UV light. Why ultraviolet and not visible light? Most UV lights gets blocked by Earth’s atmosphere, but not on the moon, where its next-to-nothing atmosphere allows ultraviolet light to pass straight down to the surface.

The spiral galaxy called the "Pinwheel" (M101) in the Big Dipper photographed in UV light from the Chang'e 3 lander. It's the first image of a galaxy ever taken with a robotic telescope from the surface of the moon. Credit: National Astronomical Observatories of China & International Lunar Observatory Association; University of Hawaii Hilo, Canada France Hawaii Telescope
The spiral galaxy called the “Pinwheel” (M101) in the Big Dipper photographed in UV light from the Chang’e 3 lander. It’s the first image of a galaxy ever taken with a robotic telescope from the surface of the moon. Credit: National Astronomical Observatories of China & International Lunar Observatory Association; University of Hawaii Hilo, Canada France Hawaii Telescope

No atmosphere also means no blurring from atmospheric turbulence. Stars beam a steady light without twinkling as seen from the moon. One other big plus results from the moon’s very slow rotation. Since it takes 27 days to spin once, nights are 27 times as long. As the stars creep 27 slower across the sky, the telescope can remain focused on the same object for days.

The Pinwheel Galaxy seen in visible light with the Hubble Space Telescope. Credit: NASA/ESA
The Pinwheel Galaxy seen in visible light with the Hubble Space Telescope. Credit: NASA/ESA

The LUT features a light-gathering mirror just 5.9 inches (150 mm) across, but that’s big enough to capture stars down to 13th magnitude. As detailed in a recent paper, the scope’s been taking about 10,000 images per month over the past 18 months and studying variables or stars that vary in brightness over days and months – sometimes hours! Unfortunately, I could only track down one photograph despite the volumes that must exist. It shows a large galaxy in the Big Dipper nicknamed the “Pinwheel”. UV light is especially good at picking up the light given off by hot, young stars and star-forming regions, seen as bright blobs outlining the galaxy’s spiral arms.

UV photo of the Earth taken by the Apollo 16 astronauts in April 1972. The side facing the sun reflects a lot of ultraviolet light, but the night side shows bands of auroral UV emission, too. Credit: NASA
UV photo of the Earth taken by the Apollo 16 astronauts in April 1972. The bright side facing the sun reflects a lot of ultraviolet light, but the night side shows bands of aurora giving off UV light, too. Credit: NASA

China’s may be the first robotic scope on the moon, but the Apollo 16 astronauts set up a 3-inch (7.6 cm) Far Ultraviolet Camera-Spectrograph telescope on the lunar regolith way back in April 1972 and took photos and spectra of the Earth and aurora, star clusters and one of the nearest galaxies, the Large Magellanic Cloud. Their haul came to 178 photo on a film cartridge which was returned to Earth for analysis. The images would be the subject of many research papers for years to come.

Apollo 16 astronauts use the Far UV camera, here seen in the shadow of the "Orion" lunar module in April 1972. Credit: NASA
Apollo 16 astronauts John Young and Charlie Duke operated the Far UV camera-telescope seen here in the shadow of the “Orion” lunar module in April 1972. Credit: NASA

While I understand the scientific importance of getting UV images of the night sky, if I could go to the moon, I’d bring a portable reflecting telescope like the one I use here at home. Without the jittery and often soft images caused by atmospheric turbulence, I could use my highest magnification to get rock-steady, crisp images of everything. Astronomical nirvana!

The Chang'e 3 lander which continues to operate on the moon's surface. Photo taken by the Yutu rover. Credit: Chinese Academy of Science
The Chang’e 3 lander which continues to operate on the moon’s surface. Photo taken by the Yutu rover. Credit: Chinese Academy of Science

Coming back to the Chang’e 3 scope, Chinese mission control has to stow the telescope back inside the lander at each lunar sunrise and sunset due to abrasive dust thought to be aloft during those hours. The team is hoping to continue the mission past the end of the year.

Research papers with some mission results

2 Responses

  1. Giorgio Rizzarelli

    I agree about taking there a reflector (also taking advantage of the slow daily rotation for photography – good point). Let me know when you go, we go together 🙂

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