NASA unveils plan to identify huge number of undetected asteroids
NASA announces new mission to help build better defences for Earth against asteroids of a certain size, with experts revealing a surprising estimate of undetected asteroids within striking distance
READING LEVEL: ORANGE
What we know about our universe is full of black holes in more ways than one. Despite the current space race and staggering advances in our quest to explore and understand our own Milky Way galaxy* and beyond, there remains a surprising amount we simply do not know.
Take medium-sized asteroids*, for instance. While many of us already know plenty of man-made space junk is now orbiting the Earth, and that we can expect to see much more tech trash falling from the sky in the years to come, far fewer of us are aware that there are also thousands of asteroids zooming around space that haven’t yet been detected. According to the experts, our ignorance is an issue because these unknown asteroids are big enough and near enough to Earth to be a problem should one of them ever collide with a populated part of our planet.
In fact, NASA estimates there are about 15,000 undetected medium-sized rocks within striking distance of the globe. While the 2022 DART* mission showed we could successfully nudge an asteroid off course with a rocket, the expedition leader said recently we were not really prepared to do it again in the event of a sudden emergency.
“We worry about these ‘city-killer*’ asteroids,” said DART mission chief Dr Nancy Chabot, from Johns Hopkins University in the US.
“DART was a great demonstration – but we don’t have that sitting around ready to go if there was a threat we needed to use it for. We don’t know where 50 per cent of the 140m asteroids are, which is a concern.”
But while Dr Chabot was clear we were not set up to actively deflect an asteroid of that size right now, she also said we could develop that capability.
“We could be prepared but I don’t see that investment being made,” she said.
Speaking at the conference of the American Association for the Advancement of Science (AAAS) in Arizona, NASA HQ planetary defence officer Dr Kelly Fast said medium-sized asteroids worried her the most.
“(It’s) the asteroids we don’t know about,” Dr Fast said. “Small stuff is hitting us all the time, so we’re not so much worried about that.
“And we’re not so worried about the large ones from the movies because we know where they are.
“It’s the ones in between, about 140m and larger, that could really do regional rather than global damage and we don’t know where they are.
“It’s estimated there are about 25,000 of those and we’re only about 40 per cent of the way through. It takes time to find them, even with the best telescopes.”
In response to this knowledge gap in asteroid risk mitigation* plans, NASA announced it would seek to address the blind-spot by launching a mission called Surveyor. Due to commence in 2027, the Surveyor team will try to find at least 90 per cent of asteroids measuring wider than 140m within a decade.
The original version of this story was published by The Sun and this edited version is republished with permission.
POLL
GLOSSARY
- Milky Way galaxy: a large spiral galaxy, our sun and all the planets and stars around it (our solar system) are part of the Milky Way
- asteroids:
- DART: the 2022 Double Asteroid Redirection Test mission when the DART spaceship deliberately struck an asteroid in a historic test of humanity's ability to divert a cosmic object from a collision course with our planet
- city-killer: an informal astronomical term for an asteroid or comet big enough to destroy a city upon impact
- mitigation: reducing how harmful, unpleasant, or bad something could be
EXTRA READING
Earth’s problem with space junk
Why this gigantic star went dark
Astronauts journey to next frontier
QUICK QUIZ
- What is the name of our galaxy?
- How many medium-sized rocks does NASA think are within striking distance of Earth?
- Why isn’t NASA so concerned about the “deep impact” Hollywood film-style asteroids?
- What did the DART mission show?
- What is the size of the asteroids the Surveyor mission will be hunting?
LISTEN TO THIS STORY
CLASSROOM ACTIVITIES
1. Scripting the scene
Imagine a scenario in which scientists meet with world leaders (real or fictional) to discuss the need for making rockets that could knock an asteroid off course. How do you think this conversation would go? What facts would the scientists want to convey? What questions or concerns might the world leaders raise?
Write a script based on how you imagine this meeting would transpire.
Time: allow 25 minutes to complete this activity
Curriculum Links: English
2. Extension
In a small group, act out the script that you created in the task above. Try to capture the feelings and attitude of your character in your acting.
Time: allow 10 minutes to complete this activity
Curriculum Links: English, Drama
VCOP ACTIVITY
To sum it up
After reading the article, use your comprehension skills to summarise in a maximum of three sentences what the article is about.
Think about:
- What is the main topic or idea?
- What is an important or interesting fact?
- Who was involved (people or places)?
Use your VCOP skills to re-read your summary to make sure it is clear, specific and well punctuated.