Huge asteroid passes Earth at 43,000 miles per hour next week

Amateur astronomers may be able to catch a glimpse of a huge asteroid that is TWICE the size of the Empire State Building as it passes Earth at 43,000 miles per hour next week

  • 小行星 7482 (1994 PC1) was first discovered by Australian astronomers in 1994
  • 星期二 (一月 18) it will pass within 1.2 million miles of our home planet
  • This is the closest it has been since 1933 when it came 699,000 离地球几英里
  • Amateur astronomers may be able to catch a glimpse of an asteroid twice the size of the Empire State Building when passes Earth at 43,000 miles per hour next week.

    小行星, 被称为 7482 (1994 PC1) and estimated to be 3,451 脚 (1.052公里) 在直径上, will fly by Earth next Tuesday, 一月 18, according to experts at 美国宇航局.

    It will safely pass within 1.2 million miles of Earth – marking the closest it has been to our planet since 1933 when it was 699,000 几英里以外.

    而 7482 (1994 PC1) is unlikely to be visible with the naked eye, amateur astronomers may be able to see it with a telescope, 根据 EarthSky.com.

    After its close approach at 16:51 和 (21:51 格林威治标准时间) 星期二, it won’t be this close to Earth again until the year 2105.

    A massive asteroid, more than twice the size of the Empire State Building in New York, 会进入 1.2 million miles of the Earth on January 18, according to NASA

    A massive asteroid, more than twice the size of the Empire State Building in New York, 会进入 1.2 million miles of the Earth on January 18, according to NASA

    太空岩石, 叫 7482 (1994 PC1), poses no threat to the Earth as it will be five times further away from the planet than the Moon, as it shoots by at 43,000 英里每小时 (图为, an artist's impression of an asteroid)

    太空岩石, 叫 7482 (1994 PC1), poses no threat to the Earth as it will be five times further away from the planet than the Moon, as it shoots by at 43,000 英里每小时 (图为, an artist’s impression of an asteroid)

    ASTEROID 7482 (1994 PC1)

    太空岩石 7482 (1994 PC1) was first discovered in 1994.

    It was spotted by RH McNaught using the Siding observatory in Australia.

    It orbits the Sun every 572 天, although has an eccentric orbit taking it from 0.9 至 1.8 AU from the star.

    One AU is the distance between the Earth and the Sun.

    The last known approach this close was in 1933, when it was 699,000 离地球几英里.

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    小行星 7482 (1994 PC1), which orbits the Sun every 1.5 年份, was first discovered in 1994 by astronomer RH McNaught using the Siding observatory in Australia.

    Its orbit is very well known, 根据天文学家, and varies from 0.9 AU to 1.8 到, 哪里 1 AU is the distance between the Earth and the Sun.

    It is a common stony S-type asteroid, and every close approach gives astronomers the chance to study the surface and learn more about these ancient space rocks.

    NASA and other agencies regularly track more than 28,000 known asteroids as they orbit the Sun, and occasionally cross Earth’s orbit.

    NASA says none of the known asteroids are expected to collide with the Earth at any point in the near future, but there are asteroids whose orbits aren’t known.

    小行星 1994 PC1 won’t even be the only space rock to make a close approach on January 18, 然而.

    It will be joined by the 70-foot 2021 BA, which will come 2.3 million miles of the planet, or about twice as far away as 1994 PC1.

    Asteroids and other space objects are being monitored by NASA’s Center for Near Earth Object Studies. It defines 7482 (1994 PC1) as a near-Earth object (NEO) and a potentially hazardous asteroid (PHA).

    近地天体是一颗小行星或彗星,其轨道将其带入或通过大约介于两者之间的区域 91 万和 121 million miles (195 million km) 从太阳, 意味着它可以在大约 30 million miles百万英里km) 万公里 (库存图片)

    近地天体是一颗小行星或彗星,其轨道将其带入或通过大约介于两者之间的区域 91 万和 121 百万英里 (195 万公里) 从太阳, 意味着它可以在大约 30 百万英里 (50 万公里) 地球轨道 (库存图片)

    空间岩石的不同类型

    一个 小行星 是碰撞或早期太阳系留下的一大块岩石. 大多数位于主带火星和木星之间.

    一种 彗星 是一块被冰覆盖的岩石, 甲烷和其他化合物. 它们的轨道将它们带离太阳系更远.

    一种 流星 当碎片燃烧时,天文学家称之为大气中的闪光.

    这种碎片本身被称为 流星体. 大多数都太小了,它们在大气中蒸发了.

    如果有任何流星体到达地球, 它被称为 陨石.

    流星, 流星体和陨石通常起源于小行星和彗星.

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    近地天体是一颗小行星或彗星,其轨道将其带入或通过大约介于两者之间的区域 91 万和 121 百万英里 (195 万公里) 从太阳, 意味着它可以在大约 30 百万英里 (50 万公里) 地球轨道.

    如果对象大于 460 脚 (140 米) 跨越, 被认为是潜在危险的物体 (HO).

    “近地天体是彗星和小行星,它们受到附近行星的引力吸引而进入轨道,从而使它们能够进入地球附近,’ 美国宇航局说.

    ‘主要由水冰和嵌入的尘埃颗粒组成, 彗星最初形成于寒冷的外行星系统,而大多数岩石小行星形成于火星与木星轨道之间的较暖的内部太阳系。.

    ‘对彗星和小行星的科学兴趣很大程度上是由于它们的地位,因为太阳系形成过程中残留的碎片相对不变, 4.6 十亿年前。’

    根据 公开提供的NASA数据, 曾经有 27,948 发现NEO, 截至周二.

    估计大约有 25,000 近地物体 (近地天体) 比大 460 脚 (140 米).

    而且还有一个估计 1,000 NEO大于 3,280 脚 (一公里), 强调需要跟踪这些太空岩石.

    一般, 每个地球都会受到足球场大小的岩石的撞击 5,000 年份, 每百万年有一个文明终结的小行星, 根据NASA的近地天体计划.

    The rock is 3,280ft in diameter, and after its close approach on January 18, 2022, 在 16:51 和 (21:51 格林威治标准时间), it won't be this close to the Earth again until 2105

    The rock is 3,280ft in diameter, and after its close approach on January 18, 2022, 在 16:51 和 (21:51 格林威治标准时间), it won’t be this close to the Earth again until 2105

    WHAT IS THE NASA DART MISSION?

    DART will be the world’s first planetary defence test mission.

    It is heading for the small moonlet asteroid Dimorphos, which orbits a larger companion asteroid called Didymos.

    When it gets there it will be intentionally crashing into the asteroid to slightly change its orbit.

    While neither asteroid poses a threat to Earth, DART’s kinetic impact will prove that a spacecraft can autonomously navigate to a target asteroid and kinetically impact it.

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    In an attempt to tackle the threat of asteroids that may one day get a little too close for comfort, NASA formed a planetary defence program, that includes the Double Asteroid Redirection Test (DART) 使命, 那 launched in November.

    DART was launched on a SpaceX Falcon 9 rocket and will see the probe deliberately crash head first into the surface of an asteroid in October this year,

    It is heading for the small moonlet asteroid Dimorphos, which orbits a larger companion asteroid called Didymos.

    When it gets there it will be intentionally crashing into the asteroid to slightly change its orbit.

    While neither asteroid poses a threat to Earth, DART’s kinetic impact will prove that a spacecraft can autonomously navigate to a target asteroid and kinetically impact it.

    然后, using Earth-based telescopes to measure the effects of the impact on the asteroid system, the mission will enhance modelling and predictive capabilities to help us better prepare for an actual asteroid threat should one ever be discovered.

    The DART technique could prove useful for altering the course of an asteroid years or decades before it bears down on Earth with the potential for catastrophe.

    DART will smash into Dimorphos, which orbits a larger asteroid called Didymos, 在 13,500 英里每小时 (21,700 km per hour). Dimorphos is depicted here to scale with Rome's Colosseum

    DART will smash into Dimorphos, which orbits a larger asteroid called Didymos, 在 13,500 英里每小时 (21,700 km per hour). Dimorphos is depicted here to scale with Rome’s Colosseum








    A small nudge ‘would add up to a big change in its future position, and then the asteroid and the Earth wouldn’t be on a collision course,’ 美国宇航局说.

    Scientists constantly search for asteroids and plot their courses to determine whether they could hit the planet.

    ‘Although there isn’t a currently known asteroid that’s on an impact course with the Earth, we do know that there is a large population of near-Earth asteroids out there,’ said Lindley Johnson, NASA’s Planetary Defense Officer.

    DEFLECTING AN ASTEROID WOULD REQUIRE ‘MULTIPLE BUMPS’, STUDY SAYS

    Deflecting an asteroid such as Bennu, which has a small chance of hitting Earth in about a century and a half, could require multiple small impacts from some sort of massive human-made deflection device, 根据专家.

    Scientists in California have been firing projectiles at meteorites to simulate the best methods of altering the course of an asteroid so that it wouldn’t hit Earth.

    According to the results so far, an asteroid like Bennu that is rich in carbon could need several small bumps to charge its course.

    Bennu, which is about a third of a mile wide, has a slightly greater chance of hitting Earth than previously thought, 美国宇航局 显露.

    The space agency upgraded the risk of Bennu impacting Earth at some point over the next 300 years to one in 1,750.

    Bennu also has a one-in-2,700 chance of hitting Earth on the afternoon of September 24, 2182, according to the NASA study.

    Scientists have been seriously considering how to stop an asteroid from ever hitting Earth since the 1960s, but previous approaches have generally involved theories on how to blow the cosmic object into thousands of pieces.

    The problem with this is these pieces could potentially zoom towards Earth and present almost as dangerous and humanity-threatening an issue as the original asteroid.

    A more recent approach, called kinetic impact deflection (KID), involves firing something into space that more gently bumps the asteroid off course, away from Earth, while keeping it intact.

    Recent KID efforts were outlined at the 84th annual meeting of the Meteoritical Society held in Chicago and led by Dr George Flynn, a physicist at State University of New York, Plattsburgh.

    ‘You might have to use multiple impacts,’ Dr Flynn said in conversation with 纽约时报. '它 [Bennu] may barely miss, but barely missing is enough.

    Researchers have been working at NASA’s Ames Vertical Gun Range, built in the 1960s during the Apollo era and based at Moffett Federal Airfield in California’s Silicon Valley, for the recent KID experiments.

    They fired small, spherical aluminum projectiles at meteorites suspended by pieces of nylon string.

    The team used 32 meteorites – which are fragments of asteroids that have fallen to Earth from space – that were mostly purchased from private dealers.

    The tests have allowed them to work out at what point momentum from a human-made object fired towards an asteroid turns it into thousands of fragments, rather than knocking it off course as desired.

    ‘If you break it into pieces, some of those pieces may still be on a collision course with Earth,’ Dr Flynn said.

    Carbonaceous chondrite (C-type) asteroids, such as Bennu, are the most common in the solar system.

    They are darker than other asteroids due to the presence of carbon and are some of the most ancient objects in the solar system – dating back to its birth.

    According to the findings from experiments at AVGR, the type of asteroid being targeted (and how much carbon it has in it) may dictate how much momentum would be directed at it from any human-made KID device.

    From the experiments, the researchers found C-type meteorites could withstand only about one-sixth of the momentum that the other chondrites could withstand before shattering.

    ‘[C-type] asteroids are much more difficult to deflect without disruption than ordinary chondrite asteroids,’ the experts concluded.

    ‘These results indicate multiple successive impacts may be required to deflect rather than disrupt asteroids, particularly carbonaceous asteroids.

    因此, 周围 160 years in the future – when Bennu is most likely to collide with Earth, according to NASA – a KID device would have to give it a series of gentle nudges to prevent it from breaking up and sending dangerous splinter fragments flying towards Earth.

    NASA’s recent study about Bennu, published in the journal Icarus, did point out there is more than a 99.9 per cent probability Bennu will not smash into Earth over the next three centuries.

    ‘Although the chances of it hitting Earth are very low, Bennu remains one of the two most hazardous known asteroids in our solar system, along with another asteroid called 1950 DA,’ 美国宇航局在一份声明中说.

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