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The Life Cycle of a Star (with NASA images)

Updated: May 28, 2023

In your physics lessons you have seen this diagram for the life cycle of a star.

Let's take your understanding further by looking at amazingly detailed images from NASA.

NASA's telescopes can observe astronomical objects in more than just visible light. There are seven other types of light that objects in space emit, but are invisible to humans. Some examples we will see are infrared waves, x rays and radio waves.

  1. Nebula

Before a newly born star (protostar) can form, it starts as clouds of gas and dust that clump together by the force of gravity. The Hubble Space telescope snapped an image of the 'Pillars of Creation' - large structures of dust within the Eagle Nebula where many stars have formed. Hubble observes space using visible light.

The even more powerful James Webb Space Telescope (also called Webb) reveals never before seen detail. Webb observes space using near infra red light (invisible to the human eye). Here the dust appears transparent as the hotter stars are more visible.

Webb also observes in the mid-infrared wavelength. Stars do not emit much mid-infrared light so the dust is easier to see. The dust is important as it is a key ingredient for stars to form.

2. Protostar

At the centre of this hourglass shape of dust and gas is a newly formed star. Can you spot it? The dust fuels its growth.

3. Main Sequence Star

A NASA image of our Sun, a main sequence star. This is the most stable stage of the its life. The sun is neither solid or liquid, but plasma - a fiery ball of gas that behaves like a liquid.

4. Red Giant Star

When the star has finished burning its fuel its outer layers expand. When our Sun becomes a Red Giant it will engulf the first 3 planets in the solar system, including Earth. The heavy elements in our bodies come from these red giant stars. As the temperature and pressure are so intense, helium fuses into the element, Carbon. On earth, organisms are based on the element Carbon.

5. White Dwarf Star

Here we see a dying red giant star. Its outer layers of gas and dust are being released into space. If you look closely you can see the tiny core of this dying star - a blue-hot white dwarf star.

A Binary Star System - Red Giant and White Dwarf

This illustration of two stars interacting - RS Ophiuchi (original image below) shows that as the stars orbit each other, the stream of gas from the red giant star moves to white dwarf and causes it to grow. The white dwarf star will eventually explode in a huge and powerful supernova.

RS Ophiuchi - original image below.

6. Supernova

After a star explodes we see huge amounts of dust and gas where elements were formed spread across the universe. Below is the Crab Nebula. Even heavier elements such as Iron and beyond are formed here.

7. Neutron Star

Here we see a different supernova explosion. At the centre the core of the star collapses. This forms an incredibly hot and dense neutron star that emits X rays.

8. Supermassive Black Hole

When a supermassive star explodes it will form a black hole which ruptures the fabric of space and time. The force of gravity is so strong here that nothing including light can escape.

Here is an illustration of a supermassive black hole.

Here an image from the Event Horizon Telescope. It shows the heating ring of the black hole emitting radio waves.


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