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Space travel comes with risk − and SpaceX’s Polaris Dawn mission will push the envelope further than any private mission has before

Space is an unnatural environment for humans. We can’t for more than two minutes. Getting to space involves being strapped to a barely contained .

Author


  • Chris Impey

    University Distinguished Professor of Astronomy, University of Arizona

Since 1961, have been into space. Private space companies such as and hope to boost that number to many thousands, and SpaceX is already for flights to Earth orbit.

who has written extensively about space travel, about our future off-Earth. I think a lot about the risks and rewards of exploring space.

As the commercial space industry takes off, there will be accidents and people will die. Polaris Dawn, planned to launch early in September 2024, will be a high-risk mission using only civilian astronauts. So, now is a good time to assess the risks and rewards of leaving the Earth.

Space travel is dangerous

Most Americans vividly recall the disasters that led to the loss of 14 astronauts’ lives. Two of the five space shuttles disintegrated, in 1986 soon after launch and in 2003 on reentry.

In total, and cosmonauts have died while training for or during space missions.

There have also been dozens of . Two astronauts are currently staying on the International Space Station for an extra six months because NASA declared their vehicle unsafe for the return journey. Starliner has had during its development, including flammable tape, stuck valves and inadequate parachute systems. But a critical thruster malfunction is what caused NASA to abandon it as a return vehicle.

It’s not always safe on the ground, either. In addition to the three who died in a 1967 launch pad fire, in the of an unmanned rocket in Russia in 1960, and hundreds died in 1996 when a Chinese and crashed into a nearby village.

The fatality rate of people traveling in space is about 3%. That sounds low, but it’s higher than such as BASE jumping or jumping off a cliff wearing a wingsuit. The only recreations that are solo free-climbing and climbing above 19,685 feet (6,000 meters) in the Himalayas.

Civilians in space

The 2020s have kicked off the era of civilian astronauts. After the death of schoolteacher , NASA stopped sending civilians into space. But for commercial space companies, it’s part of the business model.

The to reach orbit rode a SpaceX Dragon spacecraft in 2021, the Inspiration 4 mission. Since 2020, have gone to space, although only 46 reached the – the formal definition of the edge of space.

The commercial space industry’s safety record is not perfect. No civilian has died in space, but and another was seriously injured in a test flight of Virgin Galactic’s SpaceShipTwo craft in 2014. This accident followed in an explosion during a prelaunch test of the SpaceShipTwo rocket in 2007.

SpaceX, the with 13,000 employees and a market value of US$180 billion, has seen no fatalities in flight, but it has recorded in the workplace.

The Polaris Dawn mission , though a helium leak and bad weather has delayed it. It will push the envelope of risk for civilians in space. This SpaceX flight will reach an altitude of 435 miles (700 kilometers), higher than any astronauts since Apollo.

The Polaris Dawn’s four-person civilian crew will receive a , getting as much in a few hours as they would in 20 years on the Earth. to understand the extent of the health risks from radiation.

The mission will also include a – the first for nongovernment astronauts. It will use spacesuits never tested in space. Since the spacecraft they’re using – the SpaceX Dragon – has no airlock, the inside of the capsule will be exposed to the vacuum of space, with all the crew members wearing spacesuits.

Russian cosmonaut nearly died during the first spacewalk in 1965, and have led to temporary blindness, near drowning and nearly being lost in space forever. A spacesuit is like a miniature spacecraft, and it has to withstand rapid temperature changes of hundreds of degrees when moving in and out of direct sunlight. Even a small tear or puncture can be fatal.

But while space travel comes with dangers, it also has rewards. Since Polaris Dawn will travel higher than any previous mission that did not go to the Moon, the crew will be able to do . They will investigate the effects of spaceflight on the human body and evaluate how future deep-space travelers might diagnose and treat themselves.

A less tangible but potentially profound benefit is the – many astronauts report a feeling of awe from experiencing the Earth from space.

Space boom

Space is booming – hopefully just metaphorically and not literally. by launching Starlink satellites and ferrying supplies and people to the International Space Station, with estimated revenues of this year. and has contracts with NASA.

Both companies sell rides into space to high-net-worth individuals, but that’s a small fraction of their revenues. is not available to the masses yet. Virgin Galactic offers a short, suborbital ride for $450,000, but getting to Earth orbit will cost you $55 million.

The space tourism market was $750 million in 2023, and that’s projected to grow to $5.2 billion over the next decade. have made the 10 times cheaper than it was a decade ago.

For space tourism to take off with a demographic broader than multimillionaires and thrill-seekers, it needs to be safe – both in perception and in reality. Many space entrepreneurs expect space travel to follow aviation’s arc, which also started by attracting rich people and thrill-seekers.

Since 1930, improvements in technology and safety features have lowered the number of per million miles flown by a factor of 3,000. A more realistic target may be to make . That’s a more lenient target, since . Your annual odds of dying in a car crash are 1 in 5,000, compared with annual odds of 1 in 11 million of dying in a plane crash.

In the United States, the government has kept on the commercial space industry to encourage entrepreneurs.

of millions of passengers and a city on Mars may not become reality. But if the cost of a jaunt to Earth’s orbit comes down to the cost of a high-end cruise, many people could experience the thrill of weightlessness and of seeing the Earth as a beautiful planet from above.

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