[ti:European and Japanese Spacecraft Examines Mercury’s Pole ]
[by:www.21voa.com]
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[00:00.04]A spacecraft recently sent back
[00:03.56]some of the best close-up pictures yet
[00:07.32]of the planet Mercury's north pole.
[00:11.64]The European and Japanese robotic explorer
[00:15.56]went as close as 295 kilometers
[00:19.88]above Mercury's night side before passing directly
[00:24.96]over the planet's north pole.
[00:28.00]The European Space Agency (ESA)
[00:31.64]released images that show craters
[00:34.72]with deep shadows
[00:36.32]on our solar system's smallest planet.
[00:39.48]ESA noted that the edges,
[00:43.08]or rims, of the craters called Prokofiev,
[00:47.04]Kandinsky, Tolkien and Gordimer
[00:50.52]create permanent shadows.
[00:52.92]As a result, these unlit craters
[00:56.84]are some of the coldest places
[00:59.60]in the Solar System
[01:01.60]even though Mercury
[01:03.04]is the closest planet to the sun.
[01:07.32]Cameras also took images
[01:09.76]of neighboring volcanic plains
[01:12.48]known as Borealis Planitia.
[01:15.84]ESA noted that these are "Mercury's
[01:19.24]largest expanse of ‘smooth plains'
[01:22.76]and were formed by the widespread
[01:25.24]eruption of...lava 3.7 billion years ago."
[01:30.64]Also appearing in the images released by ESA
[01:35.08]is Mercury's largest impact crater,
[01:38.24]the Caloris Basin,
[01:40.16]which covers more than 1,500 kilometers.
[01:44.96]This was the sixth
[01:47.44]and final flyby of Mercury
[01:50.32]for the BepiColombo spacecraft
[01:53.48]since its launch in 2018.
[01:56.72]The recent move put the spacecraft on a path
[02:00.60]to enter orbit around Mercury late next year.
[02:05.16]The spacecraft holds two orbiters,
[02:08.60]one from Europe and the other from Japan,
[02:12.16]that will circle the planet's poles.
[02:15.04]In a statement on its website,
[02:18.56]ESA noted that Mercury,
[02:21.08]a small, dry planet,
[02:23.08]is "the least explored planet
[02:26.00]of the inner Solar System.
[02:28.28]Learning more about Mercury
[02:31.00]will shed light on the history
[02:33.68]of the entire Solar System."
[02:36.76]The spacecraft is named
[02:39.16]for the late Giuseppe (Bepi) Colombo,
[02:43.24]an Italian mathematician.
[02:45.72]Colombo played a part in NASA's
[02:49.08]Mariner 10 mission to Mercury in the 1970s
[02:54.04]and, 20 years later,
[02:56.60]in the Italian Space Agency's special satellite project
[03:01.04]that flew on the U.S. Space Shuttle.
[03:05.16]I'm John Russell. 更多听力请访问21VOA.COM