When royalty pays a visit, you can bet television cameras will be involved—especially on the moon.
The Kaguya (Selene) lunar orbiter, a Japanese spacecraft nicknamed after a legendary moon princess, launched in 2007 carrying two high-definition TV cameras, which it used to capture stunning video and pictures of the lunar surface.
Although the mission ended in 2009, this week the Japanese space agency released the entire haul of digital images captured by Kaguya during its lifetime. Some of the images have never been seen before by the public.
The story of Kaguya dates back to the 10th century and tells of a strange, beautiful girl discovered by a bamboo cutter and raised as his daughter. The child turns out to be a heavenly being from the moon, and she eventually returns to her people.
Fittingly, many of the pictures from the space probe’s HD cameras captured remarkable views of Earth as seen from the moon, including scenes of our home world rising, setting, and shining as a crescent against the blackness of space.
In addition to the HD cameras, Kaguya carried a suite of instruments designed to study the moon’s composition and structure, helping scientists determine how the moon formed and what resources might be available for future human missions.
For instance, pictures of the moon’s mysterious far side unveiled in 2008 revealed much younger volcanism than expected, hinting that the moon was geologically active for far longer than scientists thought.
And in 2009, Kaguya captured an image of a “skylight” on the moon—a dark hole that may lead to an underground lava tube. Such structures are considered ideal places to build bases on distant worlds like the moon and Mars, because the natural caves would offer protection from punishing cosmic radiation.
Data from Kaguya also revealed a potential hazard for future lunar visitors: A strong electric field forms near the lunar surface around the time of a full moon, when the lunar orb swings through the magnetic “tail” streaming off Earth.
"It is quite possible that electric fields induce a charge-up and subsequent discharge around a space vehicle, which could bring about serious damages to the human missions," study leader Yuki Harada, then a graduate student at Kyoto University, told National Geographic in 2010.
Just as the fairy tale princess could not remain on Earth, the Kaguya spacecraft wasn’t meant to last at the moon. The Japanese space agency deliberately crashed the probe into the moon’s cratered highlands in 2009. But the newly released pictures show that the short-lived mission continues to have a powerful impact on our understanding of our only natural satellite.