When I was in middle school, my biology teacher showed our class the sci-fi movie “Star Trek III: The Search for Spock.”

The plot drew me in, with its depiction of the “Genesis Project” – a new technology that transformed a dead alien world into one brimming with life.

After watching the movie, my teacher asked us to write an essay about such technology. Was it realistic? Was it ethical? And to channel our inner Spock: Was it logical? This assignment had a huge impact on me.

Fast-forward to today, and I’m an engineer and professor developing technologies to extend the human presence beyond Earth.

For example: I’m working on advanced propulsion systems to take spacecraft beyond Earth’s orbit. I’m helping to develop lunar construction technologies to support NASA’s goal of long-term human presence on the Moon. And I’ve been on a team that showed how to 3D-print habitats on Mars.

To sustain people beyond Earth will take a lot of time, energy and imagination. But engineers and scientists have started to chip away at the many challenges.

A partial checklist: Food, water, shelter, air

After the Moon, the next logical place for humans to live beyond Earth is Mars.

But is it possible to terraform Mars – that is, transform it to resemble the Earth and support life? Or is that just the musings of science fiction?

To live on Mars, humans will need liquid water, food, shelter and an atmosphere with enough oxygen to breathe and thick enough to retain heat and protect against radiation from the Sun.

But the Martian atmosphere is almost all carbon dioxide, with virtually no oxygen. And it’s very thin – only about 1% as dense as the Earth’s.

The less dense an atmosphere, the less heat it can hold on to. Earth’s atmosphere is thick enough to retain enough heat to sustain life by what’s known as the greenhouse effect.

But on Mars, the atmosphere is so slight that the nighttime temperature drops routinely to 150 degrees below zero Fahrenheit (-101 degrees Celsius).

So what’s the best way to give Mars an atmosphere?

Although Mars has no active volcanoes now – at least as far as we know – scientists could trigger volcanic eruptions via nuclear explosions. The gases trapped deep in a volcano would be released and then drift into the atmosphere. But that scheme is a bit harebrained, because the explosions would also introduce deadly radioactive material into the air.

A better idea: Redirecting water-rich comets and asteroids to crash into Mars. That too would release gases from below the planet’s surface into the atmosphere while also releasing the water found in the comets. NASA has already demonstrated that it is possible to redirect asteroids – but relatively large ones, and lots of them, are needed to make a difference.

Making Mars cozy

There are numerous ways to heat up the planet. For instance, gigantic mirrors, built in space and placed in orbit around Mars, could reflect sunlight to the surface and warm it up.

One recent study proposed that Mars colonists could spread aerogel, an ultralight solid material, on the ground. The aerogel would act as insulation and trap heat. This could be done all over Mars, including the polar ice caps, where the aerogel could melt the existing ice to make liquid water.

To grow food, you need soil. On Earth, soil is composed of five ingredients: minerals, organic matter, living organisms, gases and water.

But Mars is covered in a blanket of loose, dustlike material called regolith. Think of it as Martian sand. The regolith contains few nutrients, not enough for healthy plant growth, and it hosts some nasty chemicals called perchlorates, used on Earth in fireworks and explosives.

Cleaning up the regolith and turning it into something viable wouldn’t be easy. What the alien soil needs is some Martian fertilizer, maybe made by adding extremophiles to it – hardy microbes imported from Earth that can survive even the harshest conditions. Genetically engineered organisms are also a possibility.

Through photosynthesis, these organisms would begin converting carbon dioxide to oxygen. Eventually, as Mars became more life-friendly to Earthlike organisms, colonists could introduce more complex plants and even animals.

Providing oxygen, water and food in the right proportions is extraordinarily complex. On Earth, scientists have tried to simulate this in Biosphere 2, a closed-off ecosystem featuring ocean, tropical and desert habitats. Although all of Biosphere 2’s environments are controlled, even there scientists struggle to get the balance right. Mother Nature really knows what she is doing.

A house on Mars

Buildings could be 3D-printed; initially, they would need to be pressurized and protected until Mars acquired Earthlike temperatures and air. NASA’s Moon-to-Mars Planetary Autonomous Construction Technologies program is researching how to do exactly this.

There are many more challenges. For example, unlike Earth, Mars has no magnetosphere, which protects a planet from solar wind and cosmic radiation. Without a magnetic field, too much radiation gets through for living things to stay healthy. There are ways to create a magnetic field, but so far the science is highly speculative.

In fact, all of the technologies I’ve described are far beyond current capabilities at the scale needed to terraform Mars. Developing them would take enormous amounts of research and money, probably much more than possible in the near term. Although the Genesis device from “Star Trek III” could terraform a planet in a matter of minutes, terraforming Mars would take centuries or even millennia.

And there are a lot of ethical questions to resolve before people get started on turning Mars into another Earth. Is it right to make such drastic permanent changes to another planet?

If this all leaves you disappointed, don’t be. As scientists create innovations to terraform Mars, we’ll also use them to make life better on Earth. Remember the technology we’re developing to print 3D habitats on Mars? Right now, I’m part of a group of scientists and engineers employing that very same technology to print homes here on Earth – which will help address the world’s housing shortage.

This article is republished from The Conversation under a Creative Commons license. Read the original article.

This image provided by NASA shows the InSight Mars lander in a selfie photo composite on April 24, 2022, the 1,211th Martian day, or sol, of the mission.
| Photo Credit: AP

An immense reservoir of liquid water may reside deep under the surface of Mars within fractured igneous rocks, holding enough to fill an ocean that would cover the entire surface of Earth’s planetary neighbor.

That is the conclusion of scientists based on seismic data obtained by NASA’s robotic InSight lander during a mission that helped decipher the interior of Mars. The water, located about 7.2 to 12.4 miles (11.5 to 20 km) below the Martian surface, potentially offers conditions favorable to sustain microbial life, either in the past or now, the researchers said.

“At these depths, the crust is warm enough for water to exist as a liquid. At more shallow depths, the water would be frozen as ice,” said planetary scientist Vashan Wright of the University of California, San Diego’s Scripps Institution of Oceanography, lead author of the study published on Monday in the journal Proceedings of the National Academy of Sciences.

Also Read | Scientists propose warming up Mars using heat-trapping ‘glitter’

“On Earth, we find microbial life deep underground where rocks are saturated with water and there is an energy source,” added planetary scientist and study co-author Michael Manga of the University of California, Berkeley.

The InSight lander touched down in 2018 to study the deep interior of Mars, gathering data on the planet’s various layers, from its liquid metal core to its mantle and its crust. The InSight mission ended in 2022.

“InSight was able to measure the speed of seismic waves and how they change with depth. The speed of seismic waves depends on what the rock is made of, where it has cracks and what fills the cracks,” Mr. Wright said. “We combined the measured seismic wave speed, gravity measurements and rock physics models. The rock physics models are the same as the ones we use to measure properties of aquifers on Earth or map oil and gas resources underground.”

The data indicated the presence of this reservoir of liquid water within fractured igneous rocks – formed in the cooling and solidification of magma or lava – in the Martian crust, the planet’s outermost layer.

“A mid-crust whose rocks are cracked and filled with liquid water best explains both seismic and gravity data,” Mr. Wright said. “The water exists within fractures. If the InSight location is representative and you extract all the water from the fractures in the mid-crust, we estimate that the water would fill a 1-2 km deep (0.6-1.2 miles) ocean on Mars globally.”

The Martian surface is cold and desolate today but once was warm and wet. That changed more than 3 billion years ago. The study suggests that much of the water that had been on the Martian surface did not escape into space, but rather filtered down into the crust.

“Early Mars had liquid water on its surface in rivers, lakes and possibly oceans. The crust on Mars could also have been full of water from very early in its history, too,” Mr. Manga said. “On Earth, groundwater underground infiltrated from the surface, and we expect this to be similar to the history of water on Mars. This must have occurred during a time when the upper crust was warmer than it is today.”

Water would be a vital resource if humankind ever is to place astronauts on the Martian surface or establish some sort of long-term settlement. Mars harbors water in the form of ice at its polar regions and in its subsurface. But the depth of the apparent underground liquid water would make it difficult to access.

“Drilling to these depths is very challenging. Looking for places where geological activity expels this water, possibly the tectonically active Cerberus Fossae (a region in the northern hemisphere of Mars), is an alternative to looking for deep liquids,” Mr. Manga said, though he noted that concerns about protecting the Martian environment would need to be addressed.

The planet Mars is shown in this NASA Hubble Space Telescope view taken May 12, 2016.
| Photo Credit: Reuters

Seismic waves generated by a meteorite impact on the other side of Mars from where NASA’s InSight lander sits have provided new clues about the Red Planet’s deep interior, prompting scientists to reappraise the anatomy of Earth’s planetary neighbour.

The new seismic data indicates the presence of a hitherto unknown layer of molten rock surrounding a liquid metallic core – the planet’s innermost component – that is smaller and denser than previously estimated, researchers said on Wednesday.

Waves generated by quakes – including those caused by meteorite impacts – vary in speed and shape when journeying through different materials inside a planet. Data from InSight’s seismometer instrument has enabled the planet’s internal structure to come into focus.

The meteorite impact that occurred in a Martian highland region called Tempe Terra on Sept. 18, 2021, triggered a magnitude 4.2 quake and left a crater about 425 feet (130 meters) wide. It occurred on the opposite side of Mars from InSight’s location in a plains region called Elysium Planitia.

Also Read | Scientists surprised by source of largest quake detected on Mars

“The importance of the far side impact was to produce seismic waves that traversed the deep interior of the planet, including the core. Previously, we had not observed any seismic waves that had transited the core. We had only seen reflections from the top of the core,” said planetary scientist Amir Khan of ETH Zürich in Switzerland, lead author of one of two scientific papers on the new findings published in the journal Nature.

The behaviour of the waves indicated that previous assessments of the Martian interior were missing something – the presence of a molten silicate layer about 90 miles (150 km) thick surrounding the core. This molten region sits at the bottom of the interior portion of the planet called the mantle.

The researchers also recalculated the size of the core, finding that it has a diameter of about 2,080 miles (3,350 km), with a volume about 30% smaller than previously thought.

The researchers said the mantle – a rocky layer sandwiched between the planet’s outermost crust and core – extends about 1,055 miles (1,700 km) below the surface. Unlike Mars, Earth has no molten layer around its core. One of the two studies published on Wednesday indicates this layer is fully molten, with the other indicating that most of it is fully molten, with the top portion partially molten.

Also Read | Meet the scientist (sort of) spending a year on Mars

“The molten and partially molten layer is essentially composed of silicates (rock-forming minerals) that are enriched in iron and in radioactive heat-producing elements compared to the overlying solid mantle,” said Henri Samuel, a planetary scientist with the French national research organization CNRS working at Institut de Physique du Globe de Paris and lead author of the second study.

The Martian core is made up mostly of iron and nickel, but also has some lighter elements such as sulfur, oxygen, carbon and hydrogen. The researchers concluded that these lighter elements make up about 9-15% of the core’s composition by weight, lower than previously estimated.

“This amount of light elements is not unlike that of the Earth’s core, which is estimated to be around 10%,” Khan said.

Mars, the fourth planet from the sun, has a diameter of about 4,220 miles (6,791 km), compared to Earth’s diameter of about 7,926 miles (12,755 km). Earth is almost seven times larger in total volume.

NASA retired InSight in 2022 after four years of operations.

“We have learned a lot about Mars by studying the unique seismic record provided by the InSight mission,” Samuel said. “Planets are rich and complex systems because they are a place where many different types of processes coexist and act on various spatial and temporal scales, and Mars is no exception.”