20 Nov 2024

With NASA’s fleet of heliophysics spacecraft, scientists monitor our Sun and investigate its influences throughout the solar system. However, the fleet’s constant watch and often-unique perspectives sometimes create opportunities to make discoveries that no one expected, helping us to solve mysteries about of the solar system and beyond.

Here are five examples of breakthroughs made by NASA heliophysics missions in other fields of science.

Thousands and Thousands of Comets

The SOHO mission — short for Solar and Heliospheric Observatory, which is a joint mission between ESA (European Space Agency) and NASA — has a coronagraph that blocks out the Sun in order to see the Sun’s faint outer atmosphere, or corona. 

It turns out SOHO’s coronagraph also makes it easy to spot sungrazing comets, those that pass so close to the Sun that other observatories can’t see them against the brightness of our star.

Before SOHO was launched in December 1995, fewer than 20 sungrazing comets were known. Since then, SOHO has discovered more than 5,000. 

The vast number of comets discovered using SOHO has allowed scientists to learn more about sungrazing comets and identify comet families, descended from ancestor comets that broke up long ago.

[Image]

(A) This graphic shows missions in NASA's Heliophysics Division fleet as of July 2024.

(B) Two sungrazing comets fly close to the Sun in these images captured by ESA/NASA’s SOHO (Solar and Heliospheric Observatory). They were the 3,999th and 4,000th comets discovered in SOHO images.
(C) The background image shows the star Betelgeuse as seen by the Heliospheric Imager aboard NASA’s STEREO (Solar Terrestrial Relations Observatory) spacecraft. The inset figure shows measurements of Betelgeuse’s brightness taken by different observatories from late 2018 to late 2020. STEREO’s observations, marked in red, revealed an unexpected dimming in mid-2020 when Betelgeuse appeared too close to the Sun for other observatories to view it.

(D) Astronomers think GRB 221009A represents the birth of a new black hole formed within the heart of a collapsing star. In this artist’s concept, the black hole drives powerful jets of particles traveling near the speed of light. The jets emit X-rays and gamma rays as they stream into space.

(E) As Parker Solar Probe flew by Venus on its fourth flyby, it captured these images, strung into a video, showing bright and dark features on the nightside surface of the planet.

(F) The Hunga Tonga-Hunga Ha’apai eruption on Jan. 15, 2022, caused many effects, some illustrated here, that were felt around the world and even into space. Some of those effects, like extreme winds and unusual electric currents were picked up by NASA’s ICON (Ionospheric Connection Explorer) mission and ESA’s (the European Space Agency) Swarm. Illustration is not to scale.