Russian cosmonaut Ivan Vagner published a spectacular comet photo on his Twitter account (@ivan_mks63). He tweeted both in Russian and in English and said “During the next revolution I tried to capture the C/2020 F3 (NEOWISE) comet a bit closer, the brightest one over the last 7 years. Its tail is quite clearly visible from the International Space Station!”
C/2020 F3 (NEOWISE)
C/2020 F3 (NEOWISE), or Comet NEOWISE is a newly-discovered comet. It was discovered on March 27, 2020, by the NEOWISE space telescope (a NASA infrared-wavelength astronomical space telescope launched in December 2009 and placed in hibernation mode in February 2011 and re-activated in 2013). It is a retrograde comet with a near-parabolic orbit. It passed closest to the Sun on July 3, 2020.
In astronomy, retrograde motion is in astronomy is an orbital or rotational motion of an object in the direction opposite the rotation of its primary (in this instance, the Sun).
Comet NEOWISE had an orbital period of about 4800 years. But, its last perihelion passage (nearest point to the Sun, which was 0.29 AU or 43 million km or 26.7 million miles and occurred in June 2020) will increase it to about 6800 years.
What is a comet?
Like asteroids, comets are space rocks too. They were formed around the same time as asteroids and they are leftovers from the formation of our solar system too. However, the biggest difference between an asteroid and a comet is what they are made of. Comets are icy bodies, unlike rocky asteroids. Because they formed at farther distances from the Sun than the asteroids.
Asteroids formed toward the inner regions of our solar system where temperatures were hotter. As a result, only rock or metal could remain solid without melting. temperatures were hotter and thus only rock or metal could remain solid without melting. Comets have a solid, core structure which is known as the nucleus composed of an amalgamation of rock, dust, water ice, and frozen carbon dioxide, carbon monoxide, methane, and ammonia. That’s why they are popularly described as “dirty snowballs”.
Comets also have an extended, gravitationally unbound atmosphere surrounding their central nucleus. This atmosphere has parts termed the coma (the central part immediately surrounding the nucleus) and the tail (a typically linear section consisting of dust or gas blown out from the coma by the Sun’s light pressure or outstreaming solar wind plasma). However, extinct comets that have passed close to the Sun many times have lost nearly all of their volatile ices and dust and may come to resemble small asteroids.
Ivan Viktorovitch Vagner (born 10 July 1985) is a Russian engineer and cosmonaut who was selected in October 2010. He graduated from the Baltic State Technical University in 2008, before working as an engineer for RKK Energia.
He made his first spaceflight beginning in April 2020 as a Flight Engineer on Soyuz MS-16 and Expedition 62/63.