Growing Plants in Space: The Future of Sustenance Beyond Earth

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The Indian Space Research Organisation (ISRO) achieved a significant milestone by successfully germinating lobia (black-eyed pea) seeds in space as part of its Compact Research Module for Orbital Plant Studies (CROPS).
This development highlights the importance of cultivating plants in extra-terrestrial environments, paving the way for sustainable life on celestial bodies like the Moon and Mars.

As space missions extend over years, traditional food supplies fall short due to their limited shelf life and nutritional degradation over time.
Growing plants in space addresses these challenges by:
- Sustaining Food Supply: Plants provide a renewable source of nutrition.
- Oxygen Production: Photosynthesis in plants releases oxygen, making the air aboard spacecraft breathable.
- Recycling Systems: Plants create a closed-loop system by recycling carbon dioxide and organic waste.
- Mental Health Benefits: Tending to plants helps reduce stress and enhances astronauts’ overall well-being.

Growing plants in space presents several obstacles, primarily due to the microgravity environment:
Root Growth and Water Delivery:
- In microgravity, roots lack the directional pull of gravity and fail to grow downward.
- Water clings to surfaces rather than reaching the roots, complicating nutrient absorption.
Radiation and Temperature Fluctuations:
- High levels of radiation can damage plant DNA and hinder growth.
- Extreme temperature variations in space require insulation to protect plants.
Light Limitations:
- In regions of low sunlight, photosynthesis is disrupted, reducing oxygen production.

Scientists have developed innovative methods to grow plants in space:
- Hydroponics: Uses liquid solutions to deliver water and nutrients directly to plants, eliminating the need for soil.
- Aeroponics: Plants grow with their roots suspended in air, using mist for nutrient delivery. This method reduces water and fertiliser usage while eliminating the need for pesticides.
- Soil-like Media: Mimics terrestrial soil to support plant growth, often supplemented with slow-release fertilisers.
The ‘Veggie’ system aboard the International Space Station (ISS), a space garden about the size of a carry-on bag, exemplifies these approaches.

ISRO’s CROPS module functioned as a miniature greenhouse, simulating Earth-like conditions in space:
- Medium: Highly porous clay pellets were used, retaining water and providing nutrients via slow-release fertilisers.
- Light: Eight LEDs (four warm, four cool) simulated a 16-hour day and an 8-hour night for photosynthesis.
- Temperature and Atmosphere: Conditions were regulated between 20–30°C, with Earth-like air composition.
- Water Delivery: An electric valve controlled from Earth injected water into the soil-like medium.
The seeds germinated on the fourth day, with leaves emerging a day later, demonstrating the success of the experiment.

Cultivating plants in space is a cornerstone of future interplanetary missions.
By providing fresh food, recycling resources, and enhancing mental health, space-grown crops contribute to the sustainability of long-term extra-terrestrial habitats.
Advances like ISRO’s CROPS experiment underscore India’s growing expertise in this critical field.

The successful growth of lobia seeds in ISRO’s space module is a step forward in addressing the challenges of space farming.
As humans prepare for extended missions and the colonisation of other planets, innovations in space agriculture will play a pivotal role in ensuring sustainability and self-sufficiency beyond Earth.