Experts ponder nuclear rockets to send humans to Mars

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.

SpaceX was built to achieve Elon Musk's vision of making humans an interplanetary species

Learning quickly from early Falcon rocket failures and clashes with vendors and safety regulators, the company has focused on reusability as a first step to reaching Mars and is backed by NASA funding to do so.

NASA was founded in response to early Soviet space achievements

Although starting behind in the Space Race in 1958, NASA became a global leader in humanity's exploration of space with the Apollo program, which placed astronauts on the moon. Since then, it has been responsible for the construction of multiple telescopes, the International Space Station, and development of the Artemis program to return humans to the Moon before eventually reaching Mars.

A lunar 'satellite catapult' revives a 50-year-old idea for launching rockets

Elon Musk has proposed building a mass driver on the moon to fling satellites into space, exploiting low gravity to cut fuel and costs. The concept dates to 1970s space-settlement studies, highlighting how older industry ideas are resurfacing amid today's AI and space-infrastructure race.

NASA plans to build a lunar-orbiting space station to support future missions to Mars

Planned for a 2027 launch, NASA Gateway is a lunar-orbiting space station meant to support Artemis lunar missions and future Mars travel. This resource includes an interactive 3D model of the proposed station's modules and layout.

The Space Launch System: NASA's most powerful rocket ever

The Space Launch System is intended to be the most powerful rocket ever built by NASA. Possible missions include returning to the moon and perhaps even reaching Mars. This speculative and mostly silent video uses animation to explore the inner workings of the SLS, showing it launching and in space flight.

How reusable rocket boosters work

Reusable rockets drastically reduce the costs of space travel, saving agencies and companies millions of dollars by preserving expensive, complex boosters and their engines. The advancement required engineers to develop systems that restarted a booster in mid-flight to slow it down before landing.

Lasers could be the most cost-effective tool for clearing dangerous space debris

A NASA study found that lasers from ground- and space-based systems could utilize the momentum of light to safely push smaller debris out of their orbits. These systems would need to be accompanied by amendments to international space law, which prevents any nation from touching debris from another country, among other strategies.

NASA's ESCAPADE mission will study Mars' atmosphere

The $80M mission—a collaboration between private companies, universities, and NASA—sent two copy machine-sized orbiters on a Blue Origin rocket to the red planet to study its magnetic field and atmospheric loss.

Experiments suggest nuking a metal-rich asteroid may strengthen it

Scientists exposed meteorite samples to proton irradiation at CERN to mimic the effects of a nuclear detonation. The material exhibited greater resistance to breaking after the exposure, suggesting nuclear weapons may better serve to deflect asteroids, not break them.

Some scientists propose AI-powered satellites to monitor nuclear weapons in place of arms control treaties

With the New START treaty expired, researchers at the Federation of American Scientists have proposed using satellites and AI to remotely verify nuclear arsenals—replacing the onsite inspections that once built trust between the US and Russia during the Cold War.

Protecting astronauts against space radiation

Outside the protective atmosphere of Earth, astronauts are constantly bombarded by radiation, which, among other dangers, increases the risk cancer. While those of us on Earth can mitigate the effects of similar radiation by limiting exposure,...

NASA uses a specialized plasma wind tunnel to test heat shield technology

The ArcJet Complex ionizes compressed air that fires onto shields at hypersonic speeds, replicating the conditions of high-speed, planetary reentry. An enhanced facility incorporates lasers to mimic the radiant heating experienced during high-energy atmospheric traversal.

Nuclear-powered missiles replace chemical combustion with energy from nuclear fission

In these systems, energy is added to an airstream, which passes through a nozzle to generate thrust. Because the amount of energy released per unit mass of nuclear fuel is millions of times larger than that of chemical propellants, nuclear missiles can travel faster and farther with less fuel.

A short history of space exploration

Let us to take you back through the timeline of space exploration and its rich, fascinating history, starting in 1946, with a rudimentary German military rocket.

NASA funded research into creating pizza with a 3D printer

The agency awarded a contract for the development of devices that can create edible structures from long-lasting dry powders when mixed with liquids or pastes. By delaying this integration until the time of consumption, food could last longer than the current six-month expiration of freeze-dried meals for Mars expeditions.

Supersonic parachutes have allowed rovers to safely land on Mars' surface

The disk-band-gap parachute design was first developed for the Viking Project in the 1970s. Since then, it has been reinforced and uses stronger materials to handle larger payloads—including the 2020 Perseverance rover—landing it a world record.

Viking mission planning director Gentry Lee (1942–) on getting to Mars

"We didn't know then what we know now, which is how tough it really is to land on Mars."

How NASA measures marsquakes

Most probes sent to other planets and asteroids focus on surface phenomena, but NASA's InSight Lander is interested in looking deeper. Studying marsquakes as well as the red planet's crust and core, InSight provided four years of insight into how the rocky planets of the inner solar system formed.

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.

Small modular reactors can provide nuclear power with reduced risks and logistics

Their factory-built design allows them to be quickly installed underground, reducing their exposure to future extreme weather. They can provide power to small towns and major cities with much smaller start-up costs and reduced siting requirements.

Orbital spaceflight requires reaching 23 times the speed of sound

After the spacecraft accelerates up to at least 17,500 miles per hour, space tourists can travel in elliptical orbits hundreds of miles above Earth for days or weeks at a time. Suborbital flights instead max out at about 2,200 miles per hour and travel only 50 to 70 miles above Earth's surface for a few minutes.

Five potential ways to achieve time travel

While the author discounts the possibility of traveling to the past, it lays out five hypothetical modes of catapulting into the future: speed, gravity, suspended animation, wormholes, and light. Each has some scientific basis, but none are realistic for humans. Read the article to learn where they offer promise and where they fall short.

For decades, the US has considered building a permanent nuclear waste repository

All nuclear waste would have been stored at Nevada's Yucca Mountain, but the Obama administration indefinitely stalled the project after intense community backlash. Spent fuel is now stored at more than 80 locations in 36 states, raising safety concerns.

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.

Einstein warned the president that splitting atoms could lead to powerful bombs

In a 1939 letter to Franklin D. Roosevelt, Albert Einstein explained that nuclear fission could produce immense energy—and devastating weapons. The warning helped spur the Manhattan Project, a role Einstein later deeply regretted.

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

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.'

How fusion—which releases energy when two lighter atoms combine to form a heavier atom—differs from fission

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.

In 1984, Operation Smash Hit intentionally crashed a 239-ton train into a nuclear waste canister at 100 miles per hour to prove the canister's safety, which remained completely intact and lost just 0.29 of its 100 pounds of pressure.

Sunflowers have long been a symbol of nuclear disarmament because they can extract large amounts of radioactive cesium from soil.

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

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.

The deadliest aspect of volcanic eruptions is often not lava, but pyroclastic flows—avalanches of ash, gas, and rock that can move more than half the speed of sound.

The 2026 Ebola outbreak in the DRC is spurring new Ebola vaccine development for the Bundibugyo species.

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.

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.

11 people died from firework injuries in the US in 2024.

Larger animals like giraffes, elephants, and blue whales have developed a unique defense against cancer, a phenomenon known as Peto's Paradox

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.

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.

Listen to an in-depth conversation on the links between Parkinson's disease and herbicide exposure and the challenging pace of scientific investigation.

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.

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.

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

At the beginning of the 20th century, a group of young men ate standard American food—replete with food additives like borax and formaldehyde—as part of government research to better understand food safety.

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

Domino's Pizza's 30-minute delivery guarantee was responsible for the chain's 1980s surge, but it was discontinued after the company was found liable for delivery driver accidents.