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Read a scientific article about asteroids to practise and improve your reading skills.

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In 2010, the planetary defence team at NASA had identified and logged 90 per cent of the asteroids near Earth measuring 1km wide. These 'near-Earth objects', or NEOs, are the size of mountains and include anything within 50 million kilometres of Earth's orbit. With an estimated 50 left to log, NASA says none of the 887 it knows about are a significant danger to the planet.


Now NASA is working towards logging some of the smaller asteroids, those measuring 140 metres wide or more. Of the 25,000 estimated asteroids of this size, so far about 8,000 have been logged, leaving 17,000 unaccounted for. Considering that a 19-metre asteroid that exploded above the city of Chelyabinsk in Russia in 2013 injured 1,200 people, these middle-sized asteroids would be a serious danger if they enter Earth's orbit.


Whether NASA can find the remaining middle-sized NEOs depends on getting the money to build NEOCam, a 0.5-metre space telescope which would use infrared light to locate asteroids. If it did get the money, it could probably achieve its goal in ten years. Once logged, the planetary defence team would still need to work out how to defend the planet against being hit by the truly worrying asteroids – the PHAs.


'Potentially Hazardous Asteroids' are rocks close enough to pass within 7.5 million kilometres of Earth's orbit. NASA has created a map of 1,400 PHAs, none of which are expected to be a threat in the next one hundred years. With technology already available, NASA can track these objects and make predictions about possible impact, at which point two defence solutions could be launched.


The first is DART – the Double Asteroid Redirection Test. Plans are scheduled to test DART on the moon of an asteroid called Didymos. 'Didymoon' is 150 metres wide, orbiting its 800-metre mother, and hopefully the impact of DART will knock it out of its orbit enough for Earth-based telescopes to pick up.


Another suggested defence against a PHA on course to hit Earth is to blow it up using a nuclear weapon. It may sound like a plot from a film, and it was the subject of the 1998 film Armageddon, but the Hypervelocity Asteroid Mitigation Mission for Emergency Response (HAMMER) is a genuine NASA proposal. The eight-ton rockets would be fired at an approaching asteroid with the hope of bumping it off course. If the asteroid was too close to Earth for this plan to work, the rockets would carry nuclear bombs to blow it up instead.



Language level

Upper intermediate: B2


It is a complicated question, since if I heard that an asteroid is close to the earth, If would be advisable to report to NASA, but, obviously they would know about this information because they have all the technical equipment for know in any moment when a type of asteroid is going in the way of the earth.
If the asteroid is so big and this is will be produce a considerable impact in the surface of this planet, I would go to my home to give a very big hug to my family, to said that independently of what will happen I love all of them.

I would notify NASA about it.

It's so excited question. If i heard that an asteroid near the Earth, first of all i would try to check these news were right from NASA or fake because nowadays there are many fake news posted to get evil purpose. If these news were right, it would be hazardous for our planet. May be the asteroid will destroy total it and life no longer exists. But personally i think NASA will find anyway to solve these problem and save our planet because of its their mission.

First of all , I want to thank this platform for this information. And I appreciate your efforts to give youths this opportunity to learn. Now, I will run over this controversial question:
What would you do if you heard that an asteroid was near the earth ?
Ok I find this question very interesting. So, for me If I heard that news, I would check and double- check it. I mean I should be certain of that news. Fake news are everywhere nowadays. I believe that if this hazardous object was near the earth, it would be a horrible accident. It would destroy our planet. It would be hard to defeat this asteroid. To be honest, I think that if an asteroid attacked the earth , there would not be no solutions because it is beyond the power of humans.

The question is very interesting.
I heard these kinds of news from the others, But I did not believe that.
As I was young at that time, in the aerospace, I though that there were many myths and they gave a beautiful light to solve my dream once said when it was burning at the sky.
But I did not recognize that would be very dangerous and hazardous.
Further more, as there are many asteroids unaccounted for us, I am afraid for it.
But I believe that NASA`s working and his efforts.

Anyway, I am very wondering about this news on the existing asteroids. (: a lot of)

in my opinion , If I was surprised by a news that an asteroid is going to hit the earth, I would check the news if it is right or not.
NASA is doing a great job tracking the orbits of these hazardous asteroids ,very few ones are unaccounted for,so no need to worry.
when they pick up a dangerous object ,they make sure to log it.
Most people would freak out , however , for people who believe in fate and have faith, these things would not matter.

First of all, I would devote myself to seek whether the provided information comes from reliable sources like NASA'S. If so, there could be several potential instances: On the one hand, a threaten for an specific geographic part where the asteroid probably will hit, if by any chance such area happens to be where I reside I would be obligated to forsake it or perhaps find a bunker that can deal with the impact. On the other hand, a PHA would mean a global-scale threaten from which would be scarcely possible to escape taking for granted the possible fact that NASA'S tools may fail, which I'm afraid that would leave us no choise but to accept our extinction as human beings.

If I heard such news I will fellow the news from NASA which will give instructors like how to deal with the situation and if there are safe places to go to, the limit of steroid destruction . I think this information will reduce the feeling of panic and help people to manage the situation in proper way.

First thing to answer this question is to identify my region if it a region that exposed to asteroids dangerous or not, if yes I will obviously foster and work with any efficient efforts that will reduce the asteroids hazardous and save my life and my childrens, the second part of my answer that if my region is not, then I think I will be less active to work to limited the hazardous of the asteroids, sorry for that but that's the humans facts.

I would be scared to hear that an asteroid will be near the earth, however, we have to make sure whether the report is accurate or fake, sometimes these kind of news are fakes like the end of the world. Therefore, we have to certain with NASA who is the only means that can track this type of information. If it would be hazardous for the human race, what will be the damage and it is possible to evacuate some zones to save lives.