In just a few days, an interstellar visitor will glide past Earth, offering a rare chance to observe a comet that has traveled from beyond our solar system. Scientists and amateur astronomers alike are eager to capture its fleeting appearance.
On December 19, 3I/ATLAS will reach its closest point to Earth, coming within 167 million miles. The new-moon night provides optimal darkness for viewing. NASA confirms the comet poses no threat.
The comet was first spotted on July 1 by the Asteroid Terrestrial-impact Last Alert System (ATLAS) in Chile. Its hyperbolic orbit carried it around the Sun on October 29 before it was flung back into space. ATLAS identified it as an interstellar object.
Measurements show the body is about 3.5 miles across and has a teardrop shape in Hubble images taken on July 21. It contains an icy core surrounded by a cloud of gas and dust, similar to other comets. Estimates suggest it could be seven billion years old, older than our Sun.
The comet’s speed was 137,000 mph when first observed, accelerating to 153,000 mph as it fell into the Sun’s gravity. It will be bright enough for binoculars or a small telescope. It rises at 10:00 p.m. CST, due east near Leo, and will be best seen around 3:30 a.m. on the 21st before fading near 5:00 a.m. CST.
After passing Earth, 3I/ATLAS will travel past Jupiter and then exit the solar system, taking years to do so. NASA reports it will leave our neighborhood only in the mid-2030s. Its trajectory will slow as it escapes the Sun’s pull.
Key Takeaways
- 3I/ATLAS will approach Earth on Dec 19, within 167 million miles.
- The 3.5-mile comet is visible with binoculars and small telescopes.
- It poses no danger and will depart the solar system in the mid-2030s.
This fleeting encounter offers a unique glimpse of a body that has traversed the Milky Way, reminding us of the vastness of space and the dynamic nature of our cosmic neighborhood.
