The 45 planets astronomers think are most likely to host alien life

Where should we look for extraterrestrial life?

Not all planets are created equal. Those capable of sustaining life as we known it must meet strict criteria, the most important of which is being at the right distance from their host star to have liquid water on the surface.

Aliens may be closer to Earth than scientists have previously assumed

The hunt for extraterrestrial life is often associated with traveling far into the depths of space for clues. But answers could be closer than we think. Modern space missions have demonstrated our capability of sending probes beyond the solar system, making it plausible that other civilizations could do the same.

There may be as many as 300 million potentially habitable planets in our galaxy

The estimate comes from a study using data from the Kepler space telescope—a project aimed at finding exoplanets—and considers exoplanets similar in size to Earth around sun-like stars. These have a greater potential to possess liquid water.

Track the location of the Voyager probes, currently between 13 and 15 billion miles away from Earth.

Lining up every microbe on Earth would stretch to about 105,000 light-years

There are about 10²⁷ such organisms on the planet, many of which are adapted to produce energy through uncommon reactions in unconventional environments, such as within rocks or near volcanoes on the ocean floor. Studies of these organisms have reframed astrobiologists' search for life beyond Earth by broadening the parameters under which life can exist.

Space probes propelled by lasers may one day visit distant planetary systems

Launched in 2016, Breakthrough Starshot is a project to send gram-sized spacecraft to the nearest stars and their planets at 10% to 20% the speed of light after being accelerated by ground-based laser systems. The project requires orders of magnitude advancements to current technology.

Gaming out how our solar system might catch a new planet

If Pluto's downgraded status to a dwarf planet has got you down, consider this: Scientists think there's a chance our solar system could catch a new planet. The first ever observed so-called Interstellar Object was reported in 2017, a reddish, cigar-shaped rock astronomers named Oumuamua. Although it left in 2022, scientists believe an object with the right mass and trajectory might take a seat at the planetary table. Learn how it would work here.

The most mysterious (known) star in the universe

Something massive, with roughly 1,000 times the area of Earth, is blocking the light coming from a distant star known as KIC 8462852. One of astronomers' more intriguing theories: Alien technology. Discovered via NASA's Kepler space telescope and a...

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.

Everything you need to know about the planets in our solar system

NASA provides a re-introduction to our solar systems's planets, and a few other neighborhood residents. In the Milky Way galaxy, there are more planets than stars. We’ve discovered thousands of planets orbiting distant stars, but it all started with the current lineup of eight planets orbiting our own star—the sun. Learn more here.

The next five asteroid approaches

Asteroids are zinging by our planet regularly, and some of them you can see without a telescope. Here's a regularly updated list of the next five asteroid approaches.

New ways of seeing the cosmos have redrawn the map of human identity

From Galileo’s crude spyglass to the James Webb Space Telescope, each technological leap has expanded our observational reach and redefined philosophical and moral conceptions of our place in the universe. Identifying signs of life through the study of exoplanet atmospheres would represent the next great revolution.

Webb Telescope zooms in on Orion Nebula and finds planet pairs

The Webb telescope has trained its infrared cameras on the nearest star-forming nebula in our universe, the Orion Nebula. Its images revealed a never-before-seen phenomenon: dozens of pairs of planet-sized objects in binary orbit, seemingly floating...

A return to Uranus

There's been only one mission to Uranus before—Voyager 2 passed by the ice giant in 1986 before heading off into interstellar space. NASA's recent planned itinerary for space missions lists Uranus as the highest priority over the next decade. The seventh planet is 20 times as far from the sun as Earth, and researchers say its study will shed light on how the outer half of the Solar System formed.

Hot Jupiters are giant planets that orbit very close to their host star

Discovered in 1995, hot Jupiters are a class of exoplanets—planets orbiting stars other than the sun—with size and mass similar to Jupiter. They are most commonly found orbiting metal-rich stars and have become essential for testing theories of planetary system formation.

Asteroids were discovered by 18th-century planet hunters

While looking for a planet between Mars and Jupiter to coincide with an apparent mathematical pattern in the distances of known planets from the sun, a group calling themselves the "Celestial Police" discovered multiple objects that fell into a new classification.

The rare exoplanets orbiting distant pulsars

Pulsars are ridiculously volatile, massive, and super-dense. These objects are spread out around the universe, and their spinning magnetic fields blast out radioactive pulses. Rarely, some have planets orbiting them. There's not much hope for life there—pulsars emit regular deadly radiation—but they're still fascinating from a scientific perspective. This article further explores these amazing exoplanets.

Why haven’t humans reached Mars?

Mars remains the most viable interplanetary destination due to its relatively habitable orbit. There are many challenges, however, including the huge distance to Mars, the need for advanced propulsion systems, uncertainty over the impacts of long-duration space travel on astronauts, and the need for safe landing techniques and equipment to handle Martian conditions. Human-manned missions to Mars are not likely to occur until the 2030s at the earliest.

ESA’s Juice and NASA’s Europa Clipper will search for habitability near Jupiter

Three of Jupiter’s moons—Ganymede, Europa, and Callisto—possess subsurface oceans that may support life. While Clipper will perform flybys of Europa, Juice will be the first spacecraft to orbit a moon in the outer Solar System.

About 20% of asteroids are metal worlds similar to Earth's core

The biggest of these (that we know of) is 16 Psyche. Measuring 140 miles across, its iron and nickel content is potentially worth 10,000 quadrillion dollars. NASA’s mission to Psyche—reaching the asteroid in 2029—will study it to learn about its formation.

Lagrange points offer energy-efficient orbits for telescopes

Lagrange Points are special locations where gravitational forces let spacecraft "park" without constant course corrections, making them ideal for science missions. NASA’s James Webb Telescope uses Lagrange Point 2 to stay aligned with Earth while orbiting the Sun.

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.

Differences in the tilts of planetary orbits make perfect alignment impossible

Mercury deviates within 7 degrees of the ecliptic that marks the path of the sun, with the other planets varying from 3 degrees to approximately flat. Even an alignment within 1 degree between all eight planets is estimated to occur only once every 13.4 trillion years.

See who is in space right now

Over 600 people have been in space since the space race took off decades ago, with roughly 10 in space at any given time, typically operating the world's growing number of space stations. This fun, simple tracker keeps up on who is in space right now and provides links to each space traveler's profile.

NASA plans to bring down the ISS at a location farthest from land

Point Nemo is located in the South Pacific Ocean at coordinates 48°52.6'S 123°23.6'W, approximately 2,688 kilometers (1,670 miles) from Ducie Island, Motu Nui, and Maher Island. The location has served as an underwater graveyard for hundreds of satellites and is expected to be harbor the International Space Station in 2030.

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

Some stars take longer to form than the current age of the universe

The first stars only burned for millions of years, providing the universe's first heavy elements. Some in the current population will burn for trillions of years, delaying the appearance of black dwarfs and other exotic cold stars.

After NASA's Voyager 1 captured Earth as a single pixel as it left the solar system in 1990, astronomer Carl Sagan used the image to reflect on humanity's fragility and the responsibility to protect 'the only world we've ever known.'

Before humans, the Soviet Union and the United States sent animals—including apes, dogs, and cats—to space during the Space Race.

While the sun's gravity keeps the planets in orbit, their gravity also pulls on the sun, causing it and everything else in the solar system to orbit around a mutual balance point called the barycenter—the true center of the solar system.

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

Most of the observable universe's volume consists of voids and supervoids—enormous regions of space with little to no galaxies, stars, or light.

Stars appear to twinkle because turbulence in the motion of molecules in Earth's atmosphere causes light to bend and wiggle rapidly on its way to the surface—a phenomenon called scintillation.

Stanford built a Google Maps for the Roman Empire, revealing how much it cost to travel in the ancient world

SpaceX's S-1 or 'prospectus' revealed many previously unknown details about the company, including its unprofitability despite doing $18.7B in revenue in 2025, exactly how many voting shares Elon Musk will have in the company (roughly 85%), and more.

See how each of the more than two million known species relates to each other—and to common ancestors—in this zoomable tree of life.

In 2025, four executives from large tech companies were given positions in the US Army Reserves—including Palantir Chief Technology Officer Shyam Sankar, which reinforced Palantir's ties with the US military and its role as a leading defense partner.

While atoms are normally made of protons, neutrons, and electrons, exotic ones have been built with antimatter—alternate versions of normal matter that live for fractions of a second and are about a billion times as rare.

About 12.5% of US adults experience a phobia in their lifetime, a diagnosis that hinges on the intense fear interfering with daily life and persisting for at least six months.

As of 2025, the most cited papers in science include a review of graphene, methods to improve image recognition, streamlining electron density calculations, and optimizing protein studies.

One disco producer saw 'Star Wars' four times on its opening weekend and was so inspired that he recorded the album 'Star Wars and Other Intergalactic Funk,' which produced a chart-topping single.

In 1963, a basement renovation in Turkey revealed a passageway to a hidden, multilevel underground city that once housed as many as 20,000 people

A 2019 Facebook event called on attendees to "Storm Area 51, They Can't Stop All of Us," resulting in countless memes, the creation of a music festival, and eventually the arrests of those who did try to approach the area.

See how Budweiser's famous Clydesdales spend their days at Warm Springs Ranch, where roughly 70 to 80 of the beer brand's giant horses can be found at any given time.

About 2,000 US babies are born annually without some portion of their limbs, potentially leading to a lifetime of pricey prosthetics.

The syncytiotrophoblast is the outer layer of the placenta and the largest human cell, spanning an area about twice that of a king-sized bedsheet.

Explore a list of the 100 best novels of all time, compiled by some of the world's best living writers, including Salman Rushdie, Stephen King, and Jennifer Egan.

Search a massive database of over 4 decades of clues from the TV quiz show 'Jeopardy!'

Louisiana's 'Cancer Alley' is infamous for having some of the highest industrial pollution, toxic air emissions, and cancer risks in the US.

Frank Lloyd Wright's houses are historically hard to sell because they're old, subject to local landmark commissions, and often unfashionable