Author Archives: Florian Lienert

About Florian Lienert

Florian Lienert is a passionate scientific journalist and science volunteer with a focus on astronomy and cosmology.

Scientists developed a polymer that can deliver oxygen for germination on Mars

Although it’s little more than a barren wasteland nowadays, our planetary neighbor Mars is similar in many ways to Earth. Its length of day, dry surface area, and general relief are similar to those on Earth, which makes the Red Planet a prime target for an eventual colonization attempt.

But if we want to set up a permanent settlement on this telluric planet, there are many challenges we need to overcome — one of them, the sustainable cultivation of edible crops, has just made a revolutionary leap forward.

In a recently published paper, researchers John G. MacDonald, Karien Rodriguez and Stephen Quirk developed an oxygen delivery polymer that enabled the first successful germination in a Mars-like environment.

Sirenum Fossae – a long trough on Mars. Image credits: NASA

From seed to seedling

On Mars, there already are already some resources that we can use to grow harvestable plants. For instance, the layer of loose, soil-like material called regolith contains chemical elements such as phosphorous, iron, and potassium — all of which are needed for most plants to grow. However, until now, it has not been possible to successfully germinate plants conditions such as those on Mars.

The problem — or at least, part of the problem — is oxygen.

While plants are able to supply their own oxygen after some time, it is needed in molecular form for most plants to develop from seed to seedling. Unfortunately, the Martian atmosphere consisting of 95% carbon dioxide, contains mere traces of oxygen.

While there are types of plants capable of anoxic germination (most noticeably rice) this adaptation comes with some major drawbacks like a reduction of cellular respiration which is why they have to rely on the little efficient fermentation as an energy source.

Molecular oxygen is also needed for the redox reactions that produce generating reactive oxygen species (ROS) with essential signaling functions.

There are two ways of obtaining oxygen in a Mars-like environment: extract it from regolith metal oxides, and electrolysis. Both have some major downsides, namely time consumption and proximity to water respectively.

In a recent paper, scientists propose a different approach: they developed a polymer system. When combined with sodium hydroxide and hydrogen peroxide, the polymer becomes an oxygen infused foamed hydrogel which can deliver controlled amounts of gaseous oxygen. The foamed matrix can be mixed into the regolith or coated around the seed and can be used to grow plants.

In other words, for the first time in history, scientists succeeded in germinating plants in a martian environment. Cress, a typical test object for plant research, grew almost identically in the uninviting environment when the polymer system was used in comparison to the control group.

The findings of the scientists from Georgia, US, could mean a big step forward towards the distant possibility of a human colony on Mars.

Titan is moving away from Saturn 100 times faster than expected

Saturn’s moon Titan, an icy world shrouded by a hazy atmosphere, is the second-largest moon in our solar system, nearly 50% larger than the Earth’s moon.

In a new study published in Nature Astronomy, a team of researchers report that Titan may be straying from its planet at a much faster rate than anticipated.

Titan passing in front of Saturn — slowly drifting apart, bit by bit. Image credits: NASA / JPL.

Every moon slowly drifts away from its planet due to tidal forces. The orbiting moon exerts a gravitational pull on the planet as it orbits, creating a temporary bulge as it passes over — this is also the reason why we have high tides and low tides on Earth, for instance.

The planet’s spin sweeps the bulge forward ever so slightly, which in turn pulls on the moon and transfers it into a higher orbit. That way, the moon moves away from the planet ever so slightly each year.

So long, old friend

Previously, scientists had estimated the rate Titan moves away from Saturn to be around 0.1 cm per year. But according to recent data gathered by NASA’s Cassini spacecraft, Titan actually drifts away 100 times faster than expected, at a rate of approximately 11 centimeters each year.

These findings, while contradicting previous predictions, agree with a hypothesis proposed in 2016 by Jim Fuller, Jing Luan, and Eliot Quataert. The researchers proposed a mechanism also observed in binary stars called resonance locking, which could explain the fast migration seen in Saturn’s moon Titan. This is a process where the gravitational force of the moon squeezes the planet and forces it to oscillate. In this case, the orbital motion of Titan lines up with internal motions inside Saturn increasing the efficiency of the tidal forces and leading to a faster migration rate.

This finding also bears significant implications for the formation of Saturn’s rings and moon system (which hosts over 80 moons).

If the speed at which Titan is straying from Saturn is so large now, it implies that it was also larger in the past. This means that Titan, previously thought to have formed at a similar distance from its planet as where it is now, may have formed much closer to Saturn and then migrated outwards. This changes our understanding not only of how Saturn’s rings and moons formed but also interactions in binary star systems, galaxies, and exoplanets in close orbit to their stars.

Now, scientists await more data from the Juno space probe orbiting Jupiter which could validate the theory of resonance locking further.