Comet 3I/Atlas
Context:
NASA recently released new images of Comet 3I/Atlas.
It is an interstellar object determined to be billions of years old.
The images were captured by various missions, including the Perseverance Mars rover, MAVEN orbiter, and asteroid missions like Psyche and Lucy.
It was first spotted on July 1 by the ATLAS survey telescope in Chile.
What are Interstellar Objects?
These are celestial bodies that originate outside the solar system and travel through it.
They are not gravitationally bound to a star.
They can come from other solar systems, having been thrown into interstellar space due to collisions or being slingshotted by a planet's or star's gravity.
Most are tiny (a few hundred meters to kilometers across) and faint because they only reflect sunlight.
This makes them extremely difficult to spot against the dark background of space
About Comet 3I/Atlas:
It is the third interstellar object discovered by scientists
The first two are 1I/'Oumuamua (2017) and 21/Borisov (2019).
Trajectory & Speed:
It was traveling at a speed of 60 kmph at a distance of 670 million km from the Sun.
This high speed at such a large distance indicates it must have approached the Solar System with considerable initial speed, confirming its status as an interstellar object.
It is expected to fly closest to Earth on December 19 at a distance of 170 million miles.
Significance:
Objects like 3I/Atlas provide clues about the formation of worlds far beyond our Solar System
Analyzing their chemical composition (like ice content) can reveal conditions of their home solar systems.
For example, an ice-rich comet suggests formation far from a star before being ejected by a massive planet like Jupiter.
The European Space Agency describes them as wanderers that offer a rare, tangible connection to materials formed in environments entirely unlike our own.