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An Unusual Supernova

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Published: 11.11.2017
Level 5   |   Time: 2:19
Accent: Canadian
Source: BBC Global News Podcast (11.07.2017)

TOEFL: Scientist have discovered a supernova that is behaving in an unusual way.

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triangle Directions


  1. REVIEW the vocabulary.
  2. LISTEN to the audio above.
  3. ANSWER the questions.
  4. CHECK your answers (Show Answers)

triangle Vocabulary


  • terminal [adj] - dying
  • collapse [v] - fall down, crumple
  • explode [v] - burst violently and noisily
  • a black hole [n] - a region of space having a gravitational field so intense that no matter or radiation can escape
  • massive [adj] - very big
  • a let-up [n] - a period when something happens with less strength or intensity
  • antimatter [n] - the opposite of regular matter
  • one go [n] - one event
  • let out [phv] - release
  • a blip [n] - an unexpected, minor event different from the general trend
  • death throes [exp] - the final stage before something ends/dies

[n] - noun,  [v] - verb,  [phv] - phrasal verb,  [adj] - adjective,  [exp] - expression


triangle Guided Listening


  1. What is a supernova?
    a type of black hole
    the final explosion of a dying star
    a very large sun

  2. What usually happens to a star when it comes to the end of its life? (Choose two.)
    It collapses into a black hole.
    It changes into a planet.
    It explodes into a supernova.

  3. How much energy is released in a supernova explosion?
    the same amount of energy in 100 million suns
    the same amount of energy that is in Earth's sun
    the same amount of energy in 2 suns

  4. What is unusual about this supernova?
    Scientist were able to see it easily.
    It exploded very suddenly.
    It took longer to explode than most supernovas.

  5. How long do supernovas usually last?
    60 days
    100 days
    600 days

  6. How long did this supernova last?
    60 days
    100 days
    600 days

  7. What do scientist think was unusual about this star that went supernova? (Choose two.)
    It was very big.
    It was very small
    It was very hot.
    It was very cold.

  8. What do scientist think happened in the core of this star?
    It released extra energy.
    It collapsed.
    It produced anti-matter

  9. What does a star turn into after a supernova?
    a planet
    a neutron star
    a black hole

  10. What happened 50 years ago?
    The same star had an explosion.
    A similar type of supernova occurred.
    Scientists first discovered supernovas

  11. How long might have this star been exploding?
    5 years
    15 years
    60 years


triangle TOEFL Questions


  1. What is the discussion mainly about?
    A supernova that is following an unusual pattern.
    The amount of energy in a supernova.
    The differences between a black hole and supernova.
    How scientists observe supernovas.

  2. What two things can happen when a star dies?
    It can explode into a supernova.
    It can join another supernova.
    It can turn into a new planet.
    It can collapse into a black hole.

  3. What is the difference between a supernova and a black hole??
    A supernova is formed when a star explodes, while a black hole is formed when a star collapses.
    A black hole is formed when a star explodes, while a supernova is formed when a star collapses.
    A black hole is much bigger than a supernova.
    A black hole releases much more energy than a supernova.

  4. What does the woman suggest when she says this?

    This event may force scientist to change the way they observe supernovas.
    This event may be difficult to prove scientifically.
    This event may cause scientists to reevaluate their theories about supernovas.
    The scientist doing this research may have made many mistakes.

  5. What does the scientist mean when he says this?

    It is expensive to do this type of research.
    It is difficult to know if this event is truly unusual.
    The current equipment scientists have is not good enough.
    Most scientist will find this event hard to believe.

  6. Why does the scientist think that this supernova may have been releasing energy for many years?
    Scientist saw an explosion from this star 50 years ago.
    The star has been visible in the sky for many years.
    The supernova is about 50 light-years away from the Earth.
    Scientist have been able to measure the age of the light from the star.

  7. According to the scientist, which of these statements is true for typical supernovas?
    They release a lot of energy quickly.
    They are difficult to detect.
    They become neutron stars.
    They last about 100 days.
    They rarely occur in our galaxy.
    They usually happen at night.

  8. According to the scientist, which of these statements is true for this specific supernova?
    It is visible in the sky.
    It is lasting longer than usual.
    It likely produced antimatter.
    It came from a very large star.
    It formed close to a black hole.
    It is very hot.


triangle Script



A supernova is the terminal explosion of a dying star, but scientists have discovered a very unusual example. It doesn't seem to follow the normal pattern. So what is the normal pattern? A question for our science reporter Paul Rinkon.

Well, the normal pattern is that when a star is coming to the end of its life, it can go one of two ways. It can either collapse into a black hole, or it can explode in this massive energetic event called a supernova. And that releases the energy equivalent to 100 million suns over quite a short space of time - about 100 days. What happened in this case is that it continued for a much longer time. And that's something that people haven't seen before. Astronomers hadn't seen this before, and this seems like a very very unusual object.

And when you say a much longer time…?

Yeah. So the typical period duration for a supernova is about 100 days. It doesn't go beyond that. But this one continued for 600 days, and it continued releasing energy. There was no let up. So it released probably the amount of energy about 600 million suns, equivalent to that.

And what scientists think this means?

Well, what they think it means is that perhaps this is a very unusual type of sun that got so massive, got so big, and got so hot, that it actually produced antimatter in its core. Now this is the actual the opposite of matter. And what happens in this case is that the sun gets violently unstable, and instead of exploding in just one big go releasing all its energy and then it's gone it's reduced to this tiny neutron star, it kind of just lets it out slowly.

Now you keep saying that this is a very unusual event. Does this mean that they are going to have to rethink the way that they look at a supernova, or is this just a huge very energetic blip?

I think the universe is so big, and we haven't sampled enough of the sky. And we just haven't seen these stars before. What's also interesting is that they've seen something. They've seen an explosion from this object before - 50 years ago. And they just cannot explain that. So this may actually have been instead of 600 days, it may have been going off essentially in its death throes for 60 years or longer and letting out these short explosions without actually destroying itself in one massive supernova as happens with most stars.

That was our science reporter Paul Rinkon.