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

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.

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

The list includes familiar names like Proxima Centauri b (4 light-years away) and four planets in the TRAPPIST-1 system (about 40 light-years away), but even the nearest of those would take humanity roughly 114,000 years to reach at current spacecraft speeds. The list's real near-term value is as a targeting guide for the James Webb and upcoming Nancy Grace Roman space telescopes.

Exoplanet atmospheric gas patterns may indirectly provide evidence for life

When searching for life beyond the solar system, scientists first determine the range of distances from a star that liquid water—believed to be essential for life—can be found. Within this habitable zone, the presence of specific molecules in an exoplanet's atmosphere—detectable through spectral analysis—can indicate the presence of living things known to produce those compounds.

The Drake equation calculates the number of exoplanets that can harbor life

Developed in 1961 as part of the Search for Extra-Terrerestrial Intelligence initiative, the formula incorporates several estimated values, including the rate of star formation in the galaxy and the fraction of stars with planets.

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.

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.

There are likely millions of small black holes lurking undetected near us in space

Because black holes are so hard to spot directly, astronomers rely on models of galaxy and star evolution to estimate their population. A recent study used simulations and galactic data to show that about 1% of all matter in the universe is locked inside black holes.

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 fortunate factors that make life on Earth possible

The Earth is teeming with life while all the other exoplanets and planets aren't. A very specific set of aligned factors forms the habitability of our planet, and without just one of these fortunate factors, we might not be here. This piece lists...

Hubble revealed that planet-forming disks are common around young stars

One of Hubble’s early images captured 30 young star systems in the Orion region, each surrounded by material that looked like it was forming planets. These systems increased the number of data points scientists had to test planetary formation models.

The 'Goldilocks zone' is the region around a star where liquid water can exist

Also referred to as the habitable zone, this region varies based on the properties of a planetary system's host star, including its size and luminosity, which measure the rate at which the star radiates energy per unit area.

Gaia mapped two billion stars in the Milky Way

Using geometric parallax, the European Space Agency mission made position measurements accurate to 2.78 × 10⁻¹⁰ degrees, revealing large-scale galactic structure and dynamics. Remnants of ancient galactic mergers were also identified within the Milky Way.

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.

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.

How many galaxies are there? (Hint: a lot)

The universe is considered by some to be infinite, while others find comfort in the fact that it may have an end. Click for more.

The sun is not as exceptional as once believed, but it remains rarer than most stars

Once believed to be the center of the universe, the sun is a G-class star, the same category to which about 6% of the Milky Way's stars belong. However, the sun is younger than 85%, more massive than 95%, and more metal-rich than about 93% of all stars. Unlike the sun, half of all stars also exist in multi-star systems.

The Hubble Space Telescope made discoveries within our solar system and across the universe

The observatory helped confirm the presence of water on Jupiter's moon Europa, and uncovered seasonal variations on planets like Uranus. It also observed exoplanets and gravitational lensing, proved the existence of supermassive black holes at the centers of galaxies, and detected the accelerated expansion of the universe.

Visualize water's abundance across the solar system, and its relative rarity on Earth

Despite covering almost three-quarters of its surface, water only makes up about 0.12% of Earth's volume. Water in some of Jupiter's and Saturn's moons comprises a larger share of those celestial bodies and of the total water in the solar system. For example, Jupiter's moon Ganymede is believed to harbor almost nine times Earth's oceans beneath its icy shell.

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.

Some 19th century astronomers thought Mars was inhabited

As telescope technology advanced, astronomers became able to observe the surfaces of objects in our solar system with greater detail. The dips, valleys, and lines crisscrossing Mars, particularly, captured onlookers' imagination, leading some to speculate that the seemingly organized features could only have been created by an intelligent civilization.

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

As of 2022, scientists estimate that 117 billion people have been born on Earth

Although no demographic data exist for more than 99% of the time humans have existed, this value can be estimated by tracking approximate population sizes over different periods and the birth rates within those periods. In 2022, about 6.8% of humans that have ever been born were alive.

There may be over one trillion comets in the Kuiper Belt

Named after Gerard Kuiper, who theorized the existence of a band of icy objects beyond Neptune in 1951, direct evidence for its existence did not arrive until 1992, when the first trans-Neptunian object, besides Pluto and its moon Charon, was observed. Comets with periods of less than 200 years originate from this belt.

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

Why Earth will be made uninhabitable by the sun far sooner than when the sun dies

The star has enough fuel to continue fusing hydrogen into helium for another 5 billion years, but the gradual increase in core temperature from these reactions will brighten the sun by 10% every billion years. Some models predict that the increased radiation will be enough to vaporize all of Earth's surface water about 1 billion years from now, long before the sun becomes a red giant and disintegrates the planet.

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

There are between 10 and 100 trillion bacteria in the gut

The composition of our microbiome is essential to overall health. Anything that disrupts the balance of the trillions of bacteria may be harmful—even treatments meant to fight infection, like antibiotics.

In 2023, there were nearly as many payloads in LOE as trackable pieces of debris

In 2021, the European Space Agency estimated that more than 130 million space debris objects larger than 1 millimeter were in low Earth orbit, though only about 22,000 were being tracked. As of late 2025, the tracked total exceeds 49,000.

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

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.

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.

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.

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

Bone marrow (soft tissue found inside certain bones) generates roughly 500 billion new blood cells each day

An investigation suggests a Scottish island became awash in forever chemicals via seafoam and seaspray—raising questions about what that means for the safety of other coastal areas.

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.

Apollo astronauts left items in the moon's 'toss zone,' including golf balls, family photos, and bags of human waste, to make room for lunar rocks.

Astronauts have repaired genetic damage in space using CRISPR—a molecular tool that can make precise changes to DNA and is used in single-celled organisms to attack invasive viruses.

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

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.

Children are now three times more likely to say they want to be a YouTuber when they grow up than an astronaut, with some even attending 'YouTube camps' that teach kids how to create content for the platform.

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.

US housing costs have risen by roughly 175% between 1991 and 2026—but a growing number of Gen Zers are becoming homeowners anyway. In 2025, 4% of homebuyers were Gen Z, up from 3% the year before.

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.

In 2026, Finland was named the world's happiest country for the ninth consecutive year based on its wealth, social safety network, and high life expectancy, among other factors.

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

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.

Hookworm infection, though risky, may help fight certain autoimmune conditions by tamping down the immune system's inflammatory response.

Electrical grids worldwide must double their power delivery capacity by 2050 to meet surging demand from AI and electric vehicles.

Existentialist writer Jean-Paul Sartre coined the famous phrase 'Hell is—other people' in his play 'No Exit'