http://edition.cnn.com/2016/10/23/asia/on-japan-artificial-meteors/index.html

Japanese space start-up ALE has set out to invent artificial shooting stars.

After launching its first satellite into orbit, ALE plans to debut its meteor show in 2018.

Visible across 124 miles in diameter, each show will feature about a dozen artificial meteors in various colors.



"Imagine a future, where you can use our meteors for international fireworks displays, a proposal for marriage, or a special memorial," says Shinsuke Abe, ALE's research director and Nihon University aerospace engineering professor.

The grand showcase for this outer space entertainment could be the opening of the 2020 Olympics, in Tokyo, which ALE is rumored to have bid to take part in.

First, the team will need to launch a satellite into orbit, which will take several months to reach its position at an altitude of approximately 310 miles (500 kilometers) in the thermosphere, the second highest layer of the atmosphere.

With the ability to orbit the earth for up to four years, each satellite will store about 300 to 500 of ALE's man-made meteoroids.

A discharge device, developed by ALE, will be fitted to the satellite to eject the artificial pellets, which are about 2 centimeters in diameter.

"It's like shooting a bullet from the satellite," Abe says.

ALE's meteors will travel much slower across the sky than natural meteors -- 5 miles per second (8 kilometers per second) compared with the blistering top speed of 45 m/s (72 km/s) of the real thing -- giving spectators time to take in the show.

After a meteoroid is fired from the satellite, it will travel about one third of the way around the Earth before, ALE says, entering the atmosphere at a planned location.

The heat and friction of passing through the atmosphere cause the meteors to glow so brightly they can be seen from the ground.

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