Besides Earth, Mars is the only possibly habitable planet in our solar system

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.

The inhabitability of the Martian environment presents significant colonization risks

Terraforming the thin atmosphere, toxic dust, extreme cold, and lack of magnetic field is infeasible, given limitations to the size of what can be sent to Mars. NASA and SpaceX are instead exploring creating underground shelters.

Imagining the best places to live on Mars

Because conditions on Mars are pretty extreme for humanity, we tend not to think about living there, since everywhere on Mars feels a bit threatening. This imaginative essay uses current geographical knowledge of Mars to visualize what it would look like if humanity could alter its climate to make it widely habitable, a process known to sci-fi readers as terraforming. Given that transformation, where would the hottest neighborhoods be located?

Why extremophiles may play an important role in terraforming Mars

Possessing unique biochemicals that can detoxify extreme environments and resilience against the Martian surface that is lethal to humans, scientists are exploring whether colonies of these organisms can transform small areas of the Red Planet into future habitats for humans. Extremophiles may also be best equipped to serve as microscopic factories for the fabrication of essential polymers.

Did Mars ever look like Earth?

Mars formed at the same time as the rest of the solar system, about 4.6 billion years ago. Today, Mars is a cold, dry world with a thin atmosphere. However, there is evidence that Mars was once much more habitable, covered in flowing rivers a large bodies of water. Scientists believe over time the planet lost its magnetic field, leading to the loss of atmosphere and ultimately the evaporation of water.

Inhabiting Mars without terraforming might be accomplished with 'worldhouses'

A network of interconnected, airtight bubbles would require several orders of magnitude fewer materials than those required to re-establish the entire planet's atmosphere to resemble Earth. However, the whole network would be compromised by a single micrometeor impact that destroys the air seal.

Everything you need to know about Mars

The Lunar and Planetary Institute provides assorted resources about the red planet, Mars. Review this basic 101 level introduction and get to know our solar system neighbor. Learn about Mars' planet-wide dust storms, staggeringly high mountains (six of which dwarf Mount Everest), and whether there's water there below the surface.

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.

Planetary exploration and the search for extraterrestrial life kicked off with Viking

NASA's Viking 1 and 2 missions revealed Mars' geological activity and potential for past life through their evidence of past surface water. Viking 1 held the record for the longest Mars surface operation until the Opportunity rover surpassed it in 2010.

View the surface of Mars from NASA's Perseverance

Simulate a visit to the red planet with the Mars 2020 Perseverance Rover. This 3D interactive experience lets you explore various locations on the martian surface. See closeup images the rover has taken and view key points of interest. It's the next best thing to being there and certainly far safer!

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...

Mars features distinct geographic contrasts between its northern and southern regions

Unlike the uniform terrains found in most rocky planets, Mars has a smooth, low northern hemisphere and a rough, high southern hemisphere with much thicker crust. This dichotomy may originate from a massive collision early in the planet’s history.

Mars was named after the Roman god of war for its reddish hue, resembling blood

A single day on Mars lasts 24.6 hours, while a year lasts 687 Earth days. The rusting of iron in rocks on the Martian surface contributes to brown, gold, and tan colorations.

Dust particles on Mars can generate lightning

Through triboelectric charging, sand and dust on the Martian surface can become electrified when they rub against one another, causing friction to displace electrons and create charged particles. If this matter forms a strong enough electric field, it can overcome atmospheric insulation and produce electrical discharges, resembling lightning on Earth.

Ambient sounds on Mars are lower-pitched and more muted than those on Earth

The planet's thin atmosphere absorbs higher frequencies, and audio captured by the Perseverance rover from the Ingenuity Mars helicopter revealed that sound waves travel farther than previous atmospheric models suggested.

Experts ponder nuclear rockets to send humans to Mars

Nuclear rocket technology might be the fastest, safest way to get to the red planet. But if NASA wants to go, it should start development now.

A prototype greenhouse for Biosphere 2 is now part of a test habitat for Mars

The Space Analog for the Moon and Mars combines the Test Module greenhouse with a workshop, kitchen, common area, sleeping quarters, and a yard that mimics lunar and Martian surfaces. A blind crew member in SAM’s first mission, Inclusion I, helped assess accessibility in potential future space habitats.

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.

Earth is the only planet in our solar system with fire

And while the sun seems like fire, and other planets have volcanoes, the sun and lava aren't the same thing as fire. To produce fire, a planet needs three ingredients: oxygen, fuel, and heat. No other planet has all three.

Earth is the only terrestrial planet with a magnetic field

Its magnetosphere emerges from a complex interior process of electrical conduction, heat, and motion known as the geodynamo. The magnetic field shields the Earth from unsafe cosmic radiation, providing one of the many conditions required for life.

Stagnant lids found on Mercury, Mars, and the moon prevent tectonic activity

Unlike Earth’s lithosphere, which is composed of plates dragged by convection, the outer shells of observed terrestrial bodies in the solar system are not exposed to sufficient stress to be pulled apart. Earth is expected to develop a stagnant lid in about 1.45 billion years.

The space race of the 21st century is focused on a permanent lunar outpost

After decades of dormancy, NASA and SpaceX hope the Artemis program will provide opportunities for lunar resource extraction. Countries like India, China, and the UAE have also shown interest in developing future lunar economies.

Mar's moons, Phobos and Deimos, are thought to be captured asteroids

Of the two Martian moons, Phobos orbits more quickly, completing three revolutions a day. It gets 1.8 meters closer to Mars every year, and may crash into the planet in about 50 million years.

Fly through the Valles Marineris, the largest canyon in the solar system

Stretching farther than the width of the continental US and with depths as much as four times those of the Grand Canyon, the Valles Marineris is believed to have formed when Mars’s crust tore open during intense volcanism in the planet’s past.

Astronauts follow strict schedules to mimic Earth days and stay healthy in space

Experiencing 15 sunrises and sunsets a day while aboard the International Space Station, visitors preserve their circadian rhythms and mental health with fixed timetables. Astronauts have described sleep as living in a vacuum cleaner due to ongoing air filtration.

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.'

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

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.

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

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.

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.

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.

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

Massive 3D printers have been used to build homes by stacking layers of 'concrete toothpaste,' a fire-resistant material that effectively insulates against outside noise.

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

Human-to-human transmission of hantavirus remains extremely rare, so the 2026 hantavirus cruise ship outbreak doesn't mean we're facing a COVID-style pandemic risk.

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.

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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.

All rainbows are 'raincircles' caused by water droplets separating white sunlight into a spectrum of colors, but Earth's surface blocks the bottom half of the circle from our line of sight.

Volcanoes 'die' when their supply of magma runs out, if they are shifted away from their underlying magma reservoir, or if they get clogged by collapsing or their magma cooling back into rock.

Some renewable energy sources may weaken the resiliency of electric grids by removing outage buffers provided by coal- and natural gas-fired plants, which provide the system with more time to find a new power source if a plant goes down.

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

Apeirophobia is an overwhelming fear of living forever, perhaps stemming from the brain's inability to conceptualize an infinite life.

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.

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

Iran's Revolutionary Guard Corps is independent of Iran's regular army and is one of the most powerful and influential military-political organizations in the Middle East.

For centuries, it was common to sleep in two shifts: a few hours at the beginning of the night, and a longer period beginning around midnight

The US Constitution is widely regarded as the longest-standing written national constitution still in force—see how it has influenced rights worldwide.