NASA的新任务是在杀手小行星靠近我们之前发现它们

NASA的新任务将在杀手小行星靠近我们之前发现它们

Last July, an asteroid about the size of a football field careened closer to Earth than any celestial body has in the last century.

去年7月，一颗足球场大小的小行星倾斜着靠近地球，比上个世纪的任何天体都要近。

Just a hair closer — in the proportions of space, 40,400 miles is a pretty fine hair — and the space rock known as "2019 OK" would have delivered a devastating wake-up call.

再近一点——就太空的比例而言，40,400英里是一根相当细的头发——而被称为“2019 OK”的太空岩石将会敲响毁灭性的警钟。

NASA estimates asteroid Bennu has a 1‐in‐2,700 chance of hitting our planet during one of its close approaches in the late 22nd century. Bennu is about 1,650 feet wide. (Photo: NASA/Goddard/University of Arizona/Lockheed Martin)

Okay, so maybe it wouldn't have been the end of the world. The impact of an asteroid the size of 2019 OK would, according to NASA, level a roughly 50-square-mile area. In other words, it was a potential city killer.

好吧，也许这不是世界末日。据美国国家航空航天局称，2019年OK大小的小行星的影响相当于50平方英里的面积。换句话说，它是一个潜在的城市杀手。

Which is why NASA is taking is stepping up its asteroid-hunting strategy. The space agency is funding a new space-based telescope called the NEO Surveillance Mission designed to sniff out errant celestial bodies.

这就是为什么美国宇航局正在加快其小行星搜索战略。美国宇航局正在资助一架新的天基望远镜，名为“近地天体监视任务”(NEO Surveillance Mission)，旨在探测出偏离轨道的天体。

Currently, NASA relies on ground-based observatories such as Arizona's Catalina Sky Survey and the Pan-STARRS1 telescope in Maui. There's also the NEOWISE space mission, an orbiting telescope that began its survey back in 2010 -- although it was put into hibernation between 2010 and 2013.

目前，美国宇航局依赖于地面天文台，如亚利桑那州的卡特琳娜巡天望远镜和毛伊岛的Pan-STARRS1望远镜。还有NEOWISE太空任务，这是一架轨道望远镜，从2010年开始进行调查，尽管在2010年至2013年期间进入休眠状态。

Time to study up

是时候去关注研究了

Enter the NEO Surveillance Mission. The new eye in the sky aims to spot 90 percent of asteroids that are at least 140 meters in diameter — the size that could do real damage to the home world.

进入NEO监视任务。“天空之眼”的目标是发现90%直径至少为140米的小行星，这种大小可能对地球造成真正的破坏。

Yes, despite the occasional "sneaky" space rock, NASA already has a program in place to track asteroids and determine their threat level.

是的，尽管偶尔会有“鬼鬼祟祟”的太空岩石，NASA已经有了一个跟踪小行星并确定其威胁级别的计划。

The thing is, we don't yet have the means to destroy a killer asteroid, and even NASA concedes "no known weapon system could stop the mass because of the velocity at which it travels, an average of 12 miles per second."

问题是，我们还没有办法摧毁一颗致命的小行星，甚至美国宇航局也承认“没有任何已知的武器系统可以阻止它的质量，因为它的速度，平均每秒12英里。”

Deflection, on the other hand, may be possible, if a bit dicey.

另一方面，如果有点冒险，偏转是可能的。

That strategy would involve "rapid-response NEO reconnaissance missions." Essentially, a spacecraft would be launched toward the potential harbinger of doom in the hopes of persuading it to even slightly alter its course. We're not sure exactly how the craft would make an asteroid flinch, but even the slightest redirection could end up in wide berth for our planet.

这一战略将包括“快速反应NEO侦察任务”。从本质上讲，一艘宇宙飞船将被发射到可能预示毁灭的地方，希望能说服它稍微改变一下路线。我们不确定这艘飞船将如何让一颗小行星退缩，但即使是最轻微的改变方向，也会让我们的星球远离我们。

Unfortunately, the Trump administration pulled the plug on NASA's plan to test its asteroid-shunting capabilities with the Asteroid Redirect Mission (ARM) in 2021.

不幸的是，特朗普政府终止了NASA的计划，即在2021年用小行星重定向任务(ARM)测试其小行星分流能力。

But when the NEO Surveillance Mission hits its stride, we will at least be able to plot the trajectory of far more unwelcome visitors. And maybe, if it comes down to it, brace for impact and still have time to cue up a classic Aerosmith song or two.

但当近地天体监视任务顺利进行时，我们至少能够绘制出远比这更不受欢迎的访客的轨迹。也许，如果真的要这么做，做好准备迎接撞击，还有时间听一两首史密斯飞船(Aerosmith)的经典歌曲。