The Yaogan-30 high-revisit constellation

Satellite Observation

This article initially appeared on eastpendulum.com, a French-language blog about the Chinese military and aerospace industry

On November 24th, 2017, a Chinese CZ-2C rocket launched a trio of spy satellites. The payload was designated Yaogan-30-02, and was injected into a 600km orbit with a 35° inclination.

The Yaogan-30-01 trio The Yaogan-30-01 trio

Although China is relatively open about its military launches, not much is known about the Yaogan-30 satellites, which are a new addition to the Chinese reconnaissance system. On September 29, 2017, a first trio was launched in a similar orbit, under the designation Yaogan-30-01. China described the purpose of the satellites as being to “carry out technological experiments on electromagnetic environments“, which sounds like an euphemism for signal intelligence.

Indeed, satellite triplets are often used for signal intelligence, for instance in the American NOSS constellation or China’s own Yaogan-16, -17, -20 and -25 triplets. The advantage of…

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280 million-year-old fossil reveals origins of chimaeroid fishes

Science Life

High-definition CT scans of the fossilized skull of a 280 million-year-old fish reveal the origin of chimaeras, a group of cartilaginous fish related to sharks. Analysis of the brain case of Dwykaselachus oosthuizeni, a shark-like fossil from South Africa, shows telltale structures of the brain, major cranial nerves, nostrils and inner ear belonging to modern-day chimaeras.

This discovery, published early online in Nature on Jan. 4, allows scientists to firmly anchor chimaeroids—the last major surviving vertebrate group to be properly situated on the tree of life—in evolutionary history, and sheds light on the early development of these fish as they diverged from their deep, shared ancestry with sharks.

“Chimaeroids belong somewhere close to the sharks and rays, but there’s always been uncertainty when you search deeper in time for their evolutionary branching point,” said Michael Coates, PhD, professor of organismal biology and anatomy at the University of…

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