Feasibility of keeping Mars warm with nanoparticles

TL;DR

This paper explores the potential of using readily available nanoparticles, such as conductive nanorods, to efficiently warm Mars by scattering sunlight and blocking infrared radiation, potentially melting subsurface ice.

Contribution

It introduces a novel approach of using artificial aerosols made from common Martian materials to effectively warm the planet, surpassing traditional greenhouse gas methods.

Findings

Nanoparticles could warm Mars by over 30 K with sustained release.

Nanoparticles are more effective than greenhouse gases for warming Mars.

Climate models support feasibility of planetary warming using nanoparticles.

Abstract

One-third of Mars' surface has shallow-buried H$_2$O, but it is currently too cold for use by life. Proposals to warm Mars using greenhouse gases require a large mass of ingredients that are rare on Mars' surface. However, we show here that artificial aerosols made from materials that are readily available at Mars-for example, conductive nanorods that are ~9 $\mu$m long-could warm Mars >5 $\times$ 10$^3$ times more effectively than the best gases. Such nanoparticles forward-scatter sunlight and efficiently block upwelling thermal infrared. Similar to the natural dust of Mars, they are swept high into Mars' atmosphere, allowing delivery from the near-surface. For a particle lifetime of 10 years, two climate models indicate that sustained release at 30 liters/sec would globally warm Mars by $\gtrsim$30 K and start to melt the ice. Therefore, if nanoparticles can be made at scale on (or delivered to) Mars, then the barrier to warming of Mars appears to not be as high as previously thought.