What are Neutron Stars and Supernova Remnants?

An error occurred trying to load this video.

Try refreshing the page, or contact customer support.

Coming up next: What Are Pulsars?

You're on a roll. Keep up the good work!

Take Quiz Watch Next Lesson
Your next lesson will play in 10 seconds
  • 0:03 Stellar Death
  • 0:42 Stellar Remnants
  • 3:04 Neutron Stars
  • 8:19 Lesson Summary
Save Save Save

Want to watch this again later?

Log in or sign up to add this lesson to a Custom Course.

Log in or Sign up

Speed Speed

Recommended Lessons and Courses for You

Lesson Transcript
Instructor: Artem Cheprasov

Artem has a doctor of veterinary medicine degree.

This lesson will describe what happens after a supernova explosion occurs. Something known as a supernova remnant or neutron star may remain after the explosion, and you'll find out why that's important and how they form.

Stellar Death and New Life

When one thing dies, another is born. One day, our bodies will disintegrate into invisible atoms. But you will never truly leave planet Earth or the solar system. You'll still be here, except your atoms will be rearranged into molecules of different substances, like that of air, water, and trees, and so much more.

Death gives rise to new life. And stellar death does precisely that; it gives rise to new stars! Our lesson will explore what may remain after the death of a massive star and how new life is triggered thereafter as we discuss supernova remnants and neutron stars.

What Are Stellar Remnants?

When a supernova, a giant stellar explosion, occurs, a lot of matter is released into space. Sort of like when a balloon explodes because you squeeze it too hard; a lot of water juts out in every direction!

One thing that's released is known as a supernova remnant. A supernova remnant is simply the remains of the outer atmosphere of a massive star that has exploded that is traveling through space as an expanding shell of gas.

The supernova remnant is a marker for the explosion. This is because the explosion itself will fade away in about a year or two. But this expanding gas, the supernova remnant, is like a signal out in space telling us where the supernova explosion once was. It also carries upwards of one-fifth of the mass of the now deceased star and sweeps up more material as it travels through space.

If you could explode a grapefruit without getting acid squirted into your eyes, you'd see how the outer layers, like the peel, would travel off into the air at a very high speed. As they do so, they'll collect molecules of gas and dust in the air.

When a massive star explodes, its outer layers are also blasted into space. So fast, they can travel at supersonic breakneck speeds for thousands of years after the explosion as a shockwave.

As this shell of gas expands outwards, it can encounter the interstellar medium (ISM), the place where stars are born. The interstellar medium is filled with cosmic gas and dust, and when this shockwave coming from a supernova explosion passes through, two neat things occur.

First, the collision between the ISM and shockwave excites gas particles, resulting in the supernova remnant's beautiful glow out in space you see on your screen. This reminds me of when people pass through and collide with tiny bioluminescent organisms on ocean shores, causing the ocean to light up with pretty colors around them.

Second, when shockwaves from a supernova explosion pass through the ISM, they cause parts of the ISM to compress into very high densities, densities high enough to form new stars. Therefore, the death of one star leads to the creation of many more.

What Are Neutron Stars?

While some supernova explosions only leave a supernova remnant behind, other supernovae may leave a bit of their original core behind. This might result in the formation of a neutron star, an extremely small but highly dense sphere composed mainly of neutrons.

And while that may sound boring, there's a cool story to go along with the concept of a neutron star, supernovae explosions, and supernova remnants. On July 4, 1054, something incredible happened that was observed in China, the great city of Constantinople, and even by the Anasazi of what is now the Southwestern United States of America. It was called a 'guest star' by Yang Wei-T'e, the astronomer of the Chinese imperial court at the time.

He, and observant people around the world, noticed and recorded the appearance of a new brilliant object brighter than Venus. It was so bright, it could be seen even in daylight at the height of summer! Yang Wei-T'e wrote: 'I bow low. I have observed the apparition of a guest star. Its color was an iridescent yellow…the land will know great prosperity.' It must have been an incredible sight to behold.

But over a course of just under two years, this dazzling guest star disappeared. This guest star was actually a supernova explosion 6,500 light years away that left behind a neutron star and supernova remnant. We now see its supernova remnant as the Crab Nebula.

Under the incredibly high temperature and pressure resulting during a supernova explosion, neutron stars can form when protons and electrons are forced together. In a bit more detail, what happens is as follows. Stars that are initially less than about eight solar masses as an adult star - a main sequence star - can die relatively quietly and peacefully as a white dwarf. Stars that are initially about 8-20 solar masses end their life explosively as a neutron star.

This is because such massive stars cannot shed enough of their weight during their lifetime through things like stellar wind and the formation of planetary nebulae to leave behind a small enough core.

To unlock this lesson you must be a Study.com Member.
Create your account

Register to view this lesson

Are you a student or a teacher?

Unlock Your Education

See for yourself why 30 million people use Study.com

Become a Study.com member and start learning now.
Become a Member  Back
What teachers are saying about Study.com
Try it risk-free for 30 days

Earning College Credit

Did you know… We have over 200 college courses that prepare you to earn credit by exam that is accepted by over 1,500 colleges and universities. You can test out of the first two years of college and save thousands off your degree. Anyone can earn credit-by-exam regardless of age or education level.

To learn more, visit our Earning Credit Page

Transferring credit to the school of your choice

Not sure what college you want to attend yet? Study.com has thousands of articles about every imaginable degree, area of study and career path that can help you find the school that's right for you.

Create an account to start this course today
Try it risk-free for 30 days!
Create an account