The much talked about interstellar comet 3I/ATLAS will reach its closest point to our planet today (Friday), December 19. This marks an important moment for astronomers who have been tracking one of the most unusual objects ever observed near Earth since July. The comet was discovered on July 1 by the NASA-funded ATLAS telescope network in Chile. It is only the third confirmed interstellar object known to have passed through our solar system, after 1I/ʻOumuamua in 2017 and 2I/Borisov in 2019. Its steep, hyperbolic path shows it did not originate around the Sun and will eventually leave the solar system forever.
When is the closest approach?
According to orbital calculations from NASA Jet Propulsion Laboratory’s Horizons system, comet 3I/ATLAS will reach its minimum distance from Earth at 1 AM EST (0600 GMT) on December 19.At that time, the comet will be about 1.8 astronomical units away, roughly 168 million miles (270 million kilometers). That is nearly twice the average distance between Earth and the Sun.
Is there any danger to Earth?
No. As confirmed by NASA, the comet poses no threat to Earth or any other planet. Even at its closest point, it will still be around 170 million miles away, or more than 700 times the distance between Earth and the Moon.The European Space Agency has also stated that the flyby is entirely safe.
Why the flyby matters
Although the comet remains distant, its passage is scientifically important. As 3I/ATLAS moves through the inner solar system, heat from the Sun causes its icy nucleus to release dust and gases. Studying this material gives astronomers a rare opportunity to examine matter that formed around another star system.Observations near closest approach are especially valuable, as they allow scientists to analyze how interstellar comets behave when exposed to sunlight.In recent weeks, multiple observatories have focused on the comet. New images were released by the Hubble Space Telescope, along with observations from the JUICE Jupiter probe, capturing the object as it races through the inner solar system.
Where and how to watch
The comet will not be visible to the naked eye. However, skywatchers using a telescope with an aperture of at least 30 centimeters may be able to observe it.In the early pre-dawn hours, observers should look toward the east to northeast. The comet will appear just below Regulus, the brightest star in the constellation Leo.Because the comet is faint and moving quickly, astronomers recommend checking with local observatories or organized skywatching events for guidance before it fades further from view.
