Tag: Astrobiology

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Leto’s Children

Does Demeter know
of your lunar harvest plans?
Rooted regoliths.

Humanity has long looked at the moon and wondered if and how we could colonise it. How would we survive? What would we eat? Could we ever plant crops on the moon?

Yet for over 50 years the possibility of answering this third question has been within our reach. The Apollo 11, 12 and 17 missions all brought back samples of lunar regolith – a fine grey soil found on the moon’s surface. If earth plants can grow in lunar soil then the idea of growing crops on the moon isn’t entirely in the realm of science fiction.

With the start of NASA’s Artemis program in 2017 (which aims to get humans back to the moon by 2025) interest in the potential for lunar soil has increased. Paul et al. (2022) were given permission to test whether mouse-ear cress (Arabidopsis thaliana) would grow in lunar regolith.

They found that the plants sprouted from seeds and grew, although they were slow to develop, showed signs of stress and differentially expressed genes indicating ionic stresses. Whilst plenty of small steps are needed to understand how to mitigate these issues, the fact that the plants grew at all is a huge leap for humanity’s dreams of colonising the moon.

This poem plays with ancient Geek mythology. Leto is the goddess of motherhood and fertility and the mother of Artemis and Apollo (who the NASA space programs are named after). Demeter is the goddess of the harvest. Artemis is the goddess of the hunt, nature and the moon. Apollo is the god of the sun, music and, fittingly, poetry.

Further reading: http://dx.doi.org/10.1038/s42003-022-03334-8

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Patches on Venus

Patches on Venus:

Atmosphere harbouring the

conditions for life?

 

In the hunt for extra-terrestrial life, Venus is rarely considered due to the high surface temperatures (~465 °C) and the intense atmospheric pressure (92 times that on Earth). Yet a new study by Limaye et al (2018) suggests that life off the surface of the planet may be possible since the lower cloud layer harbours conditions suitable for microbial life: water, solutes, ~60 °C and an atmospheric pressure roughly equivalent to Earth.

What’s more, observations of Venus have revealed dark patches in the atmosphere that change shape, size and position over time. These are made up of particles roughly the same size as common Earth bacteria and also absorb light of at a similar spectrum. The changes in patch patterns could therefore be the equivalent of algae blooms.

Venus is thought to have once had water on its surface, potentially for as long as 2 billion years providing enough time for life to evolve. As the surface water evaporated the microorganisms could have been transported to the clouds, in similar ways to how bacteria have been found in the atmosphere of Earth (although on Earth aerial microbes do not appear to remain aloft indefinitely). Life on the second planet from the sun therefore remains a possibility and only further observations and potentially even atmospheric sampling will reveal whether the changing dark patches are indeed patterns of microbial life.

Original research: https://doi.org/10.1089/ast.2017.1783