Key points from article :
Harsh environment on Mars has always made growing food a daunting prospect.
Silica aerogel could transform the cold, arid surface into land fit for farming.
Sheets of aerogel would warm the ground and melt enough subsurface ice to keep plants alive.
3cm thick sheets blocked harmful UV rays and allowed visible light through for photosynthesis.
Scalable solution could cover large regions of the planet.
Alternative to terraforming that requires the whole atmosphere to be re-engineered.
The study was published in Nature Astronomy.