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Now, an asteroid that was spotted late last year by space scientists is being carefully tracked.
現在,太空科學家們正在仔細追蹤去年年底發現的一顆小行星。
Scientists are trying to work out whether there's a chance of it hitting the Earth, which could happen eight years from now.
科學家們正在努力研究它是否有可能撞擊地球,而這有可能在八年後發生。
Our science editor, Rebecca Murrell, is here with more details.
我們的科學編輯 Rebecca Murrell 將為您帶來更多詳情。
Rebecca.
麗貝卡
Thanks, Jane.
謝謝你,簡。
Well, there's still a lot we need to learn about asteroid 2024 YR4.
關於小行星 2024 YR4,我們還有很多東西需要了解。
What we do know is that it's estimated to be between 40 and 90 metres, and the date it could hit is the 22nd of December 2032.
我們所知道的是,它的高度估計在 40 到 90 米之間,撞擊日期可能是 2032 年 12 月 22 日。
Now, that chance is very small.
現在,這個機會已經很小了。
It was thought to be 1.3 per cent, but that risk has now gone up to 2 per cent.
原來認為是 1.3%,但現在這一風險已上升到 2%。
But scientists say don't panic.
但科學家們說,不要驚慌。
We talk about collision risks with these things a lot, but maybe it's better to think about the avoidance risk or the avoidance probability, and that's actually still quite high, so there's a 98 per cent chance that this object will not hit our planet, and maybe that's what we should keep in mind.
我們經常談論這些東西的碰撞風險,但也許我們更應該考慮的是規避風險或規避概率,實際上這個概率還是很高的,所以這個天體有98%的概率不會撞擊我們的星球,也許這才是我們應該牢記的。
That increase in impact risk is something that astronomers expect, and here's why.
這種撞擊風險的增加是天文學家所期待的,原因就在這裡。
When an asteroid is first spotted, we're still learning about its orbit.
第一次發現小行星時,我們還在瞭解它的軌道。
The asteroid could pass through anywhere in this red zone.
小行星可能會經過這個紅色區域的任何地方。
It's called the area of uncertainty, and it's big.
這就是所謂的不確定區域,它很大。
Now, the Earth is in it too, but the risk of a collision is low.
現在,地球也在其中,但發生碰撞的風險很低。
As we get more information, the area of uncertainty of where the asteroid might be shrinks, but now you can see that the Earth fills up more of it, so the risk increases.
隨著我們獲得的資訊越來越多,小行星可能出現的不確定區域也在縮小,但現在你可以看到地球佔據了更多的區域,是以風險也在增加。
But as we learn even more, the area of uncertainty shrinks further, hopefully to a point where the Earth is now outside of it, so there's a zero risk of a The asteroid is currently moving away from the Earth, and after May it won't be visible again until 2028, so they're using the most powerful tool they have, the James Webb Space Telescope.
但隨著我們瞭解到更多的資訊,不確定區域會進一步縮小,希望能縮小到地球現在位於不確定區域之外,是以小行星撞擊地球的風險為零。 小行星目前正在遠離地球,5 月份之後,直到 2028 年才能再次看到它,是以他們正在使用最強大的工具--詹姆斯-韋伯太空望遠鏡。
This will tell astronomers the precise size of the asteroid and more about its orbit.
這將告訴天文學家這顆小行星的精確大小,以及更多關於其軌道的資訊。
It's crucial information should we need a plan of action.
如果我們需要一個行動計劃,這是至關重要的資訊。
Although we may not be certain that at the moment this asteroid is going to hit, if it is going to hit, we know exactly when that will occur, and so we know what we need to do, for example, if we just want to evacuate an impact area, or in fact if we have enough warning time, as may be the case for this one, we can actually mount a deflection mission.
雖然我們可能無法確定這顆小行星是否會撞擊我們,但如果它真的會撞擊我們,我們就能準確知道撞擊的時間,是以我們知道我們需要做什麼,例如,如果我們只想撤離撞擊區,或者事實上,如果我們有足夠的預警時間,就像這顆小行星一樣,我們實際上可以執行偏轉任務。
NASA has already tested a deflection mission.
美國國家航空航天局已經對偏轉任務進行了測試。
It crashed a spacecraft into another small asteroid and successfully changed its orbit.
它將一個航天器撞向另一顆小行星,併成功改變了它的軌道。
But don't worry, we're not at that stage yet.
不過別擔心,我們還沒到那個階段。
Astronomers will continue to monitor this space rock.
天文學家將繼續監測這塊太空岩石。