Interstellar comet 3I/ATLAS: NASA’s latest images highlight a safe, distant flyby on December 19

A rare visitor from beyond the solar system is putting on a subtle but scientifically rich show. Interstellar comet 3I/ATLAS—only the third confirmed interstellar object detected to date—has intensified in activity as it speeds through the inner solar system. New NASA releases show jets, a brightening coma, and evolving tails, while confirming the object will pass safely and distantly by Earth on December 19, remaining roughly 170 million miles (about 1.8 AU) away.

What NASA’s new looks at 3I/ATLAS reveal

Fresh imagery from multiple NASA assets captures 3I/ATLAS in impressive detail. The Hubble Space Telescope reobserved the comet on November 30, tracking it against streaked background stars and resolving a compact nucleus wrapped in a diffuse coma with faint tail structure. Additional views from NASA heliophysics missions provide wide-field context, tracing how the dust and gas respond to the solar wind as the comet races sunward and then arcs away.

Scientists note a sustained uptick in activity since the comet rounded the Sun. Sublimating ices are driving jets that feed the coma and tails, with the morphology changing day to day as sunlight and rotation expose fresh surface regions. Some observing teams have reported periodic brightness variations, a clue to the comet’s rotation and the distribution of active vents across its surface.

Interstellar comet 3I/ATLAS: key dates and distances

3I/ATLAS has already passed its closest approach to the Sun and is now outbound on a hyperbolic, never-to-return trajectory. Here’s the essential timeline:

Even at closest approach, 3I/ATLAS remains far beyond the Moon and well outside the orbit of Earth—comfortably distant for science and entirely non-threatening for the public.

How bright is 3I/ATLAS, and can you see it?

Despite the buzz, 3I/ATLAS is not expected to become a naked-eye spectacle. Current estimates place it around magnitude ~11–12, bright enough for moderate amateur telescopes under dark skies but too faint for binoculars in most locations. Its motion is brisk—on the order of tens of miles per second—yet its great distance makes it appear to drift slowly against the stars through a single night. Positions and visibility windows vary by latitude and date; dedicated observers should consult up-to-date ephemerides and use long-exposure imaging to tease out the tails.

Why this interstellar comet matters

Interstellar objects carry ingredients and histories from other planetary systems. By dissecting the light scattered and emitted by 3I/ATLAS, researchers can:

• Compare ices and dust with those in solar-system comets to test how common certain molecules—like water, carbon dioxide, and organics—are across the galaxy.

• Probe activity physics under interstellar surface conditions, refining models for jets, dust grain sizes, and tail formation in low-gravity, low-albedo bodies.

• Constrain shape and rotation, using periodic brightness changes to infer whether the nucleus is elongated, tumbling, or bearing localized vents.

Multiple spacecraft are contributing: a deep-space asteroid probe is monitoring the comet with its onboard cameras; solar-observing missions are mapping the expanding dust and ion tails; and optical assets in Earth orbit are measuring color and structure at high resolution. Together, these vantage points create an unprecedented, multi-scale portrait of an interstellar comet under solar heating.

Safety, myths, and what’s next

With heightened attention come claims that outpace the data. The established trajectory keeps 3I/ATLAS far from Earth with no impact risk and no expected effects on satellites, power grids, or climate. Activity described as “eruptions” reflects standard cometary physics—volatile ices warming, venting, and lifting dust—not explosions or artificial phenomena.

In the coming days around December 19, expect continued releases of processed images, refined brightness measurements, and chemical clues from spectral analyses. As 3I/ATLAS recedes, its activity will wane, but the collected dataset—spanning ultraviolet to radio wavelengths—will fuel studies well into 2026, helping answer a central question: how do planetesimals formed around other stars compare to the building blocks of our own solar system?

Quick facts: 3I/ATLAS at a glance

• Type: Interstellar comet on a hyperbolic path

• Closest to Sun: Oct. 30, 2025 (~1.4 AU)

• Closest to Earth: Dec. 19, 2025 (~1.8 AU / ~170 million miles)

• Visibility: Telescope target; not naked-eye

• Status: Active, scientifically valuable, and no threat to Earth

As the interstellar wanderer exits the neighborhood, the coordinated NASA observing campaign is turning this fleeting appearance into a lasting scientific return—an extraordinary chance to sample the chemistry and behavior of a comet born under another star.