Our Sun, like all stars, has a life cycle.

The Sun goes through both short-term and long- term cycles. In the short term, every 11 years or so, the Sun's magnetic field completely flips. This is called the solar cycle. During solar maximum, when the magnetic fields are the most unstable, solar activity increases, intensifying the solar wind, causing space weather. Solar maximum can easily be observed by counting the number of sunspots. In the long term (billions of years), the Sun, like all stars, has a life cycle. Near the end of its nuclear burning stage, the star expels most of its outer material until only the hot core remains, which then settles down to become a white dwarf. That expelled outer material, primarily made of gas, is called a planetary nebula, which drifts through space, and one day, could become part of a new star, beginning the cycle again.

In this image of the Serpens Nebula from NASA’s James Webb Space Telescope, astronomers found a grouping of aligned protostellar outflows within one small region (the top left corner). Serpens is a reflection nebula, which means it’s a cloud of gas and dust that does not create its own light, but instead shines by reflecting the light from stars close to or within the nebula.

Topics: nuclear fusion, solar cycle, stellar evolution, sunspots

NGSS: PS1, LS1, ESS1

Image Credits: NASA, ESA, CSA, K. Pontoppidan (NASA’s Jet Propulsion Laboratory) and J. Green (Space Telescope Science Institute).

Framework for Heliophysics Education

Big Idea 3.3

A rectangular image with black vertical rectangles at the bottle left and top right to indicate missing data. A young star-forming region is filled with wispy orange, red, and blue layers of gas and dust. The upper left corner of the image is filled with mostly orange dust, and within that orange dust, there are several small red plumes of gas that extend from the top left to the bottom right, at the same angle. The center of the image is filled with mostly blue gas. At the center, there is one particularly bright star, that has an hourglass shadow above and below it. To the right of that is what looks a vertical eye-shaped crevice with a bright star at the center. The gas to the right of the crevice is a darker orange. Small points of light are sprinkled across the field, brightest sources in the field have extensive eight-pointed diffraction spikes that are characteristic of the Webb Telescope.

Have leaners investigate this heliophysics big idea with the guiding questions below.

  • Sun, 335 angstrom UV

    Introductory Learner (K-5)

    How was the Sun born?

  • yellow image of the Sun

    Intermediate Learner (6-8)

    What is the life cycle of stars?

  • An image of the Sun shows a bright flash in the bottom right side where a solar flare erupts.

    Advanced Learner (9-12+)

    Do other stars behave similarly to the Sun?

FRAMEWORK FOR HELIOPHYSICS EDUCATION

Heliophysics Resource Database

Use the guiding questions above to explore resources at each level or go directly to our database to search for resources by level, NGSS performance expectation, topic, and mission.

Resource Database
In this animated GIF, a small portion of the Sun appears green. A bright white flash suddenly appears on the edge of the Sun.
On Nov. 4, 2003, this solar flare saturated the X-ray detectors on several Sun-observing spacecraft.
NASA/ESA/SOHO