Explore a guide to observing comets

Find which comets are currently visible in the night sky

Incorporating sightings reported in the Comet Observation database and information from NASA's Jet Propulsion Laboratory, this list provides a finder chart, star map, tracker, simulated orbit, and key properties for each comet, all viewable based on a user's input position on Earth.

Visualize the anatomy of a comet

The solid nucleus holds the frozen molecules, which are heated into a gaseous state once the comet is within three times Earth's distance from the sun. The surrounding coma, from which comets get their name, is a spherical cloud that can grow larger than Jupiter, from which tails develop.

Read about the dangerous comet behind the Perseids meteor shower

Every summer, Earth passes through the debris trail of the Swift-Tuttle comet, producing the spectacle of the Perseids meteor shower. The phenomenon is a glorious opportunity for amateur stargazers, but astronomers have long noted the comet's orbit...

View a gallery of notable comets

The collection features 1973's Kohoutek, which had been dubbed the "comet of the century," 1965's Ikeya-Seki—one of the brightest comets of the millennium—and 2002's NEAT, a comet that survived a coronal mass ejection as it passed near the sun.

A comet's tails point away from the sun, rather than trailing its motion

The ion tail, composed of gases ionized by solar radiation and pushed by the solar wind, points away from the sun. In contrast, the dust tail is pushed away by radiative pressure and curves away from the comet's motion. As the comet approaches the sun, both tails get longer.

NASA's Stardust mission collected and returned samples from a comet

Launched in 1999, the spacecraft traveled to comet Wild 2 and captured more than 10,000 dust particles from its coma using a tennis racket-like mesh covered in aerogel. It also took pictures of the comet before returning to Earth and releasing the collection canister during its 2006 flyby.

Dark comets appear to be rocky asteroids but move like comets

Cometary orbits are known to exhibit accelerations independent of gravity that result from forces related to the release of gases. Dark comets exhibit this behavior but lack visible clouds of frozen material that have turned into a gas—the coma the comets display—indicating minor quantities of escaping subsurface ice.

View galleries of images taken by the Hubble Space Telescope

With more than 1.7 million observations made since 1990, the Hubble Space Telescope has captured images of space missions, planets, stellar nurseries, interstellar comets, star clusters, galaxies, and more. This search tool allows users to sort and filter across these celestial objects to explore over 35 years of Hubble's astrophotography.

Shooting stars, or meteors, are fragments of asteroids and comets that burn up as they enter Earth's atmosphere, creating streaks in the sky called meteor showers.

Comets can be categorized based on their orbital period

Short-period comets orbit around the sun once every 200 years or less and are made up of Jupiter-family (less than 20 years) and Halley-type (between 20 and 200 years) comet subgroups. Long-period comets have orbits greater than 200 years, while exocomets originate in solar systems outside our own.

Explore a guide to photographing auroras

Using a wide aperture and increasing your camera's native ISO to a value between 3200 and 8000, depending on atmospheric conditions, will help capture as much light as possible while freezing the movement of the auroras. The camera should also be kept as still as possible and in environments with minimal weather impediments, such as clouds.

The names of comets can change based on subsequent observations

The International Astronomical Union's coded naming system uses the first letter to indicate a comet's category, which can change over time. "D" represents comets that have been lost or broken up, while "A" applies to former comets that are now asteroids or dwarf planets.

Shooting stars, or meteors, are fragments of asteroids and comets that burn up as they enter Earth's atmosphere, creating streaks in the sky called meteor showers.

Explore the known asteroids, comets, and spacecraft involved in asteroid studies within our solar system with 'Eyes on Asteroids,' a 3D visualization from NASA.

As of 2025, scientific evidence strongly supports 3I/ATLAS being a comet

Claims of alien technology would require the celestial object to transmit measurable technological signals, which were not detected by the world's largest fully steerable radio telescope. Previous telescope observations identified that 3I/ATLAS's chemical composition, structure, and orbital characteristics are consistent with those of an interstellar comet.

A composite of telescope images of the sun, which each reveal unique solar features

While traditional cameras can reveal sunspots—cooler regions on the sun's surface—in visible light, x-ray detectors can highlight explosions of high-energy plasma and magnetic fields known as coronal mass ejections. Hydrogen-alpha filters can reveal clouds and filaments of material suspended in magnetic fields above the sun's surface.

The ancient Greeks and Romans viewed comets and meteors as divine omens

Both considered the appearance of a comet or its fragments as a precursor to significant events, such as the birth of a notable figure or the death of a ruler. One observed in 44 BCE was believed to be a sign of the deification of Julius Caesar after his assassination.

Spikes of light around stars are artifacts of light bending around the mirror supports

Through diffraction, electromagnetic waves can bend around obstacles, as observed in the silver linings at the edges of clouds, where light should be blocked. Within reflecting telescopes, starlight diffracts around struts—beams holding a secondary mirror in place—and spreads perpendicular to them, creating pairs of spikes.

How do scientists study far away stars?

Astronomy is the only science that is purely observational: meaning, scientists can't study stars in a lab. Here's a breakdown of how modern researchers use new tools to understand objects billions of light years away. As it turns out, the rules of science allow us to identify, categorize, and experiment with phenomena light years away.

See a dying star in different wavelengths

The Crab Nebula is the remnants of a dying star that went supernova . First spotted a thousand years ago by Chinese and Japanese astronomers, and likely Native Americans as well. Its original bright light has long since faded, but you can see it in different light wavelengths through this interactive website.

A guide to building your own cloud chamber to observe cosmic rays

Using felt, alcohol, dry ice, and a clear container—such as a fish tank—you can create a region of supersaturated air that will cling to passing particles, forming trails of cloud-like droplets. Muons will create straight paths, alpha particles will leave thicker ones, and electrons or positrons will zigzag.

Through 2025, two-thirds of known exoplanets have been detected via transits

This technique involves observing periodic, consistent dips in a star's brightness caused by an exoplanet passing in front of it. Observing wobbles in a star as it is pulled by an orbiting exoplanet's gravity has become the second most common detection method, followed by microlensing and direct exoplanet observation.

Galileo's Jupiter discovery shattered Earth-centered universe beliefs

Using a telescope inspired by Dutch designs, Galileo spotted four moons orbiting Jupiter in 1610, providing undeniable evidence against geocentrism and fueled support for the heliocentric model. Galileo’s original telescope design stretched 20 meters long—a feat of optical engineering for its time.

Watch the motion of an individual photon using a high-speed camera

Although light travels over 3 million football fields per second, cameras that capture trillions of frames per second can observe individual particles of light as they interact with atoms in materials they travel through. Such observations can be used to determine the speed of light in different materials.

Watch David Attenborough’s documentary on bioluminescent creatures

Sea creatures can make their bodies glow to camouflage themselves by mimicking the appearance of the night sky as seen from underwater. Species without this ability can form a symbiotic relationship with bioluminescent bacteria or eat other organisms with relevant biochemicals.

The first image of a black hole was captured by creating an Earth-sized virtual observatory from a network of eight radio telescopes.

Watch a lightning storm from the International Space Station

While passing over the Alabama and Georgia regions, NASA astronauts photographed passing thunderstorms from the ISS. The illuminated clouds are described as "nebula-like formations."

UK's Royal Astronomers join the hunt for Ramadan's crescent moon

In Britain, Muslim communities and professional astronomers now collaborate to officially spot the moon that begins Ramadan, blending ancient practice with modern science. The partnership culminates in a live, unscripted annual broadcast even.

Explore our favorite visualization of the immense scale of space, from an astronaut to the size of the observable universe

See the 25 of the best photos of auroras from around the world.

Visualize the path of every solar eclipse from 1900 to 2099 and see what each looks like when observed from different locations on Earth.

Neutron stars, the remains of some massive stars after they explode in a supernova, are the densest directly observable objects in the universe.

See how fireworks are made and learn how metals like magnesium and copper are responsible for different colors.

'Silent' fireworks have gained more interest in recent years as a quieter celebratory option.

Watch how deep-sea mining equipment collects and processes polymetallic nodules—metal-rich, potato-shaped rocks—from the ocean floor and creates environmentally damaging plumes of sediments.

Objects can be 3D printed with light by projecting 2D computerized tomography (CT) scans onto rotating cylinders of resin, which solidify upon exposure.

Browse a detailed visual analysis of over 200,000 similes—comparisons that often use 'like' or 'as'—from popular fiction to see how frequently writers the same idiomatic expressions.

Scientists can determine Earth's past climate conditions by analyzing air trapped in microscopic bubbles within ice cores—columns of compressed snow layers that build up over hundreds of thousands of years.

Explore chaos in this simulation of two double pendulums, where small differences in the release angles produce wildly different outcomes.

See photos of Meteora, a mountainous site in central Greece, home to 14th-century monasteries perched atop soaring outcroppings.

Take a 3D tour of the Hajj, Islam's annual pilgrimage to Mecca, undertaken by more than 1.5 million Muslims each year.

Explore fun facts from the USPS, including unique post office buildings, a stamp that traveled past Pluto, and more.

Learn how to read a prospectus, the juicy document that any company must file with the SEC before going public.

Hotels in Cannes, the glamorous city on the French Riviera, hire hawks to ward off seagulls during the city's famous film festival.

Memecoins are a type of cryptocurrency—a form of digital currency with a wide variety of uses—created around popular 'memes,' or viral internet jokes.

For centuries, Niagara Falls has been a magnet for daredevils seeking to conquer one of nature's most powerful wonders, with its 200-foot drop and water rushing at 32 feet per second with 280 tons of force.

Researchers believe the brain consolidates memories, processes emotions, and plans for the future during dream states

Fear or disgust related to clusters of holes and cracks, called trypophobia, may stem from evolutionary processes to help us avoid pathogens.

Long before Major League Baseball began allowing instant replay for balls and strikes, an umpire reluctantly used the technology to determine whether a hit was a home run, a move that inadvertently ushered in a new era for the sport.

To reduce wrinkles in clothing, research recommends gentle wash cycles with more water and tumble drying with smaller loads and longer times.