Venus, meet Japan. Today the Japan Aerospace Exploration Agency (JAXA) launched a rocket carrying several different missions bound for our boiling-hot sister planet. Here’s what they want to learn.

Atmospheric Tag Team

Akatsuki, the Venus climate probe, will arrive at the second planet from the sun in December. There it will team up with the European Space Agency’s Venus Express probe, using five cameras to peer down into the turbulent atmosphere and study Venus‘ maniacal meteorology.

One of the main goals is to understand the “super-rotation” of the Venus atmosphere, where violent winds drive storms and clouds at speeds of more than 220 mph (360 kilometers per hour), 60 times faster than the planet itself rotates [MSNBC].

The Venus Express’ own findings since it reached the planet in 2006 have bolstered the idea that Venus was once alive with plate tectonics, oceans, and continents—that is, it was once much more Earth-like than its current, sweaty incarnation. In fact, Venus may still be active.

Volcanoes?

It’s alive! It’s alive! (Maybe.)

Just last month, scientists working with the Venus Express reported seeing lava flows on the surface that barely showed signs of weathering. They’re young. The team argued that this is more evidence Venus is not just a shadow of its formerly active self, but could still be alive with volcanism.

The thick Venusian atmosphere is opaque to instruments that operate at visible wavelengths and so the Japanese probe carries five cameras that are sensitive in the infrared and ultraviolet parts of the electromagnetic spectrum [BBC News].

They’ll use these capabilities—infrared in particular—to scan the surface of Venus for any active volcanism.

Can We Fly This Solar Sail?

Japan’s H-IIA rocket also carried into space Japan’s solar sail project “Ikaros,” the Interplanetary Kite-craft Accelerated by Radiation of the Sun. As DISCOVER noted last month, when the sail (seen above) deploys, it will be 66 feet in diagonal distance, yet thinner than a human hair. Ikaros, named for the ill-fated mythological figure, actually has two propulsion systems. The “sail” part refers to its ability to use the tiny pressure of sunlight the way a sailboat uses the wind. But the craft is also equipped with photovoltaic cells to generate solar electricity.

The hardest part is just deploying such a large sail, project leader Osamu Mori says, which they will attempt in a few days. Ground tests of this feature proved… difficult.

“We even sent it high up in the sky in a big balloon, to spread the film in a near-vacuum environment. We experienced many failures, but we kept searching for the most reliable deployment method, and that led us to the model we’ve now built. I believe it will be successful” [BBC News].

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Image: JAXA