3I/ATLAS latest update: Where to watch the interstellar comet livestream on December 19
The rare interstellar visitor, Comet 3I/ATLAS, is now making its closest pass to Earth. Only the third object of its kind ever detected, the comet is a priority for researchers, even though its huge distance (about 170 million miles) from Earth makes it invisible to the naked eye. To see it, skywatchers need a professional-grade telescope aimed toward the constellation Leo, just below the star Regulus, in the early morning hours. A dedicated live stream by Ray's Astrophotography, however, is offering a more accessible way to watch the comet. Unlike digital simulations, this broadcast offers viewers a raw, real-time feed of the interstellar visitor as seen through a telescope based in Texas.
Astronomers are convinced that 3I/ATLAS comes from a very distant part of the galaxy. Per them, it had to drift through the Milky Way for billions of years until it reached Earth from the direction of the Sagittarius constellation. Its status as an "outsider" was confirmed by experts who analyzed its hyperbolic trajectory and very high velocity, proving that it does not orbit our Sun.
3I/ATLAS is coming in at a far greater speed than average space rocks that form in our own neighborhood. When first discovered near the orbit of Jupiter, this comet was already cruising along at 137,000 mph, per NASA. As it swung inward around the Sun, the solar gravity served as a gigantic slingshot to accelerate the object to a maximum velocity of 153,000 mph. Now that this visitor has rounded the Sun, it is maintaining its extreme velocity as it travels out toward the outer reaches of the solar system.
While the comet is now in retreat, it's not quite gone. Amateur backyard astronomers and professionals alike can still spot 3I/ATLAS with telescopes through the coming spring of 2026. But the viewing window is now starting to shut: each day, the object grows a little dimmer, a little farther away. Scientists are now racing to analyze the visitor before it's truly gone. NASA researchers are using a network of space-based and ground telescopes to study the chemical makeup of the comet to unlock secrets about the distant star system in which it was born, while the object is close enough to observe.
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