tech2 News Staff
November 16, 2018 12:48 PM IST
Deadly cosmic radiation, potential vision loss and atrophied bones are just some of the challenges scientists must overcome before any future astronauts can set foot on Mars, NASA experts and senior officials said on Tuesday.
The US space agency believes it can put humans on the Red Planet within 25 years, but the technological and medical hurdles are immense.
"The cost of solving this means that under current budgets, or slightly expanded budgets, it will take about 25 years to resolve them," said former NASA astronaut Tom Jones, who flew four space shuttle missions before to retire in 2001.
"We need to start now on certain key technologies," he told reporters in Washington.
At an average distance of about 140 million miles (225 million kilometers), Mars presents scientific problems in an order of magnitude greater than anything found by the Apollo lunar missions.
With today's rocket technology, it would take an astronaut up to nine months to get to Mars – the physical toll to float for too long at zero gravity would be huge.
For example, scientists believe that prolonged absence of weight can cause irreversible changes in the blood vessels of the retina, leading to the degradation of vision.
And after a time at zero-G, the skeleton begins to leach calcium and bone mass.
With gravity only a third of the Earth, scientists are still unaware of the effects of a supposed one-year mission on the surface of Mars.
One way to reduce human body wear is to drastically reduce travel time to Mars.
Jones called for nuclear propulsion systems that would have the added benefit of producing electricity on flights.
"If we start now, in 25 years we may have these technologies available to help us and protect us from these long transit times," he said.
Under current conditions, only a one-way trip to Mars would take so long that any astronaut would receive the same amount of radiation as would normally be considered safe throughout a career.
"We still do not have the shielding solution in terms of protection against cosmic rays and solar blasts that you experience during this transit time," Jones said.
Aerospace experts have identified a number of technologies that need rapid development, including spacecraft that can survive hard landing on Mars and land smoothly enough, as well as the ability to take people off the surface and return to Earth.
Nasa currently has a new robotic module called InSight, which is approaching Mars due to landing on Nov. 26, after taking off from California on May 5.
The $ 993 million project aims to expand human understanding of the interior conditions on Mars, inform efforts to send explorers there and reveal how rocky planets like Earth formed billions of years ago.
Jim Garvin, chief scientist at NASA's Goddard Space Flight Center, said InSight would fill "unknowns" and help build a key understanding of Mars.
In 2020, another mission will have NASA send a jeep to Mars, which aims to determine the habitability of the Martian environment, look for signs of ancient life, and assess the natural resources and hazards of future human explorers.
In addition, private companies such as SpaceX and a number of other nations are building technologies that could be used in future missions to Mars.
Some experts see the new exploration of the moon as the key to a future mission on Mars, as astronauts there could learn to draw water or use technology and apply those lessons to future missions on Mars.