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美国宇航局火星着陆# 8217年代减速系统看起来像一个不明飞行物(更新:发射推迟)

发布时间:2018-09-20 文章编辑:admin

Today, NASA is performing a new test round for its low-density supersonic decelerator (LDSD), which is basically a giant stop and brake system for heavy duty crafts landing on Mars。 Both the Curiosity Rover (2012) and the twin Viking probes (1976) used the same parachute to slow their supersonic descent and land safely on the Martian surface。 These parachutes, however, can’;t handle more than a tone worth of payload, and if humans are ever to touch the Red Planet’;s surface they’;d need to land 15 to 20 tonnes of payload –; in other words, we’;re gonna need a bigger parachute。 The LDSD system deployed by NASA and slated for a test run above the Pacific might be the technology we’;ve been waiting for。

**UPDATE:  because of unfavorable ocean conditions, NASA’;s LDSD test vehicle launch was postponed。 More details here

The LDSD system。 Image: NASA

The LDSD system。 Image: NASA

Landing a probe, rover or craft of any kind on Mars is no trifle。 The atmosphere of Mars has less than 1% the thickness of Earth’;s atmosphere but it’;s a lot thicker than that of the Moon。 This means we can’;t use the same deceleration and touch down procedures we’;ve become used to for the lunar landings, nor for Earth-bound atmospheric re-entries。 Yes, a parachute is common for landings on Earth and Mars, but since the atmosphere is much thinner the drag is proportionally lower。 To increase air resistance, the LDSD uses an inflatable doughnut-shaped airbag made from Kevlar。 This comes in two versions: the 6-meter in diameter SIAD-R meant for landing robots like the next rover bound for Mars, and the 8-meter SIAD-E for huma*****sions。

LDSD image

How it looks like alongside a human。 Image: NASA

The SIAD-E is the most interesting to us。 According to models made by NASA, the SIAD-E should slow down a manned craft, like the Orion capsule, from 2,600 mph (x3。5 speed of sound) to 1,400 mph in under three minutes。 At this point, a parachute 30。5 meters in diameter  deploys for a slow landing。

本文源自: 环亚娱乐