Recently discovered comet C / 2020 X3 (SOHO) seen in the LASCO C2 camera on the ESA / NASA SOA observatory. Credit: ESA / NASA / SOHO / Karl Battams
While Chile and Argentina witnessed a total solar eclipse on December 14, 2020, unknowingly looking at the sky, a small sparrow flew past the Sun – a recently discovered comet.
This comet was first seen in satellite data by Thai amateur astronomer Worachate Boonplod on GODMOTHERFunded Sungrazer Project – a citizen science project that invites anyone to search for and discover new comets in images from the European Space Agency (ESA) and NASA’s Solar and Heliosphere Observatory, or SOHO.
Boonplod discovered the comet on December 13, the day before the eclipse. He knew the eclipse was coming, and he was eager to see if his new discovery of the comet might appear in the Sun’s outer atmosphere like a small drop in the eclipse’s photographs.
(left) The LASCO C2 camera on the ESH / NASA SOHO observatory shows comet C / 2020 X3 (SOHO) in the lower left corner. (right) A composite image of the total solar eclipse of 14 December 2020, based on 65 frames made by Andreas Möller (Arbeitskreis Meteore eV) in Piedras del Aguila, Argentina and processed by Jay Pasachoff and Roman Vanur. Credit: ESA / NASA / SOHO / Andreas Möller (Arbeitskreis Meteore eV) / Processed by Jay Pasachoff and Roman Vanur / Joy Ng
The comet, named C / 2020 X3 (SOHO) by the Minor Planet Center, is a “Kreutz” sungrazer. This family of comets came from a large parent comet that split into smaller fragments well over a thousand years ago and continues to orbit the Sun today. Kreutz sungrazing comets are most commonly found in SOHO images. The SOHO camera works by mimicking total solar eclipses: a solid occulting disk blocks the sun’s blinding light, revealing weaker features of its outer atmosphere and other celestial objects such as comets. To date, 4,108 comets have been discovered in SOHO images, with the 3,524th Kreutz sungrazer spotted.
Around the time the eclipse was taken, the comet was traveling at about 450,000 miles per hour, about 2.7 million miles from the Sun’s surface. The comet was about 50 meters in diameter – about the length of a semi-truck. It then disintegrated into dust particles due to intense solar radiation, a few hours before reaching the point closest to the Sun.