A solution to the climate crisis: mining the moon to put dust in space, researchers say

[muriel_volestrangler]

What could possibly go wrong?

Proponents of a “moonshot” idea to deal with global heating have been handed a new, very literal, interpretation by researchers who have proposed firing plumes of moon dust from a gun into space in order to deflect the sun’s rays away from Earth.

The seemingly outlandish concept, outlined in a new research paper, would involve creating a “solar shield” in space by mining the moon of millions of tons of its dust and then “ballistically eject[ing]” it to a point in space about 1m miles from Earth, where the floating grains would partially block incoming sunlight.

“A really exciting part of our study was the realization that the natural lunar dust grains are just the right size and composition for efficiently scattering sunlight away from Earth,” said Ben Bromley, a theoretical astrophysicist at the University of Utah, who led the research, published in Plos Climate.

“Since it takes much less energy to launch these grains from the moon’s surface, as compared with an Earth launch, the ‘moonshot’ idea really stood out for us.”

https://www.theguardian.com/science/2023/feb/08/moon-dust-moonshot-geoengineering-climate-crisis

Abstract
We revisit dust placed near the Earth–Sun L1 Lagrange point as a possible climate-change mitigation measure. Our calculations include variations in grain properties and orbit solutions with lunar and planetary perturbations. To achieve sunlight attenuation of 1.8%, equivalent to about 6 days per year of an obscured Sun, the mass of dust in the scenarios we consider must exceed 1010 kg. The more promising approaches include using high-porosity, fluffy grains to increase the extinction efficiency per unit mass, and launching this material in directed jets from a platform orbiting at L1. A simpler approach is to ballistically eject dust grains from the Moon’s surface on a free trajectory toward L1, providing sun shade for several days or more. Advantages compared to an Earth launch include a ready reservoir of dust on the lunar surface and less kinetic energy required to achieve a sun-shielding orbit.
...
Space-baced approaches for solar radiation management provide an alternative. Objects in space—a large screen [10–12] or a swarm of small artificial satellites [13, 14]—that are well-positioned at the L1 Lagrange point between Earth and the Sun can efficiently shade our planet. Challenges includes maintaining orbits in the face of radiation pressure from sunlight. The optical properties of the orbiters are thus chosen to mitigate this problem. A high degree of forward scattering allows light to be deflected without transferring much photon momentum, a feat accomplished with refractive, non-absorbing material. A second challenge is that the amount of material required to provide climate-impacting shade exceeds 109 kg, which is roughly a hundred time more mass than humans have sent into space to date. However, strategies have been identified that are feasible [13].

Variations on the original proposals to shade Earth with artificial sun shields include the use of dust. Clouds of micron-size gains at the Earth–Sun L1 point [15–17], at Lagrange points of the Moon-Earth system [11, 18], and in orbit around Earth [19–21] have all shown some promise, albeit with limitations. The potential sources of dust include terrestrial and lunar mines and near-Earth asteroids. In all cases, masses ≳ 1010 kg are necessary to have climate impact.

Here, we revisit the reduction of sunlight received by Earth that results from the placement of dust at or near the inner Lagrange point, L1, lying directly between Earth and the Sun, including gravitational perturbations from the Moon and other planets. While unstable, these corotating orbits allow for the possibility of temporarily shading Earth. We start by assessing the shadows produced by various types of dust; then we numerically determine orbits that persist near L1, including the impact of radiation pressure and solar wind. Our main results are a connection between the quantity and quality of dust and the attenuation of sunlight at Earth on achievable orbits near L1. To compare with previous work, we target a reduction in solar irradiance of 1.8%, or 6 attenuation-days per year.

https://journals.plos.org/climate/article?id=10.1371/journal.pclm.0000133

[Easterncedar]

1. Cripes

Because self control is beyond us

[global1]

2. Can't Imagine What That Would Do To Any Satellites We Have Circling The Earth....nt

[relayerbob]

3. As a physicist, I can only say ....

what the fuck are they thinking? I can think of countless reasons not to do this, and not a single one that actually is makes it a good idea. It might cool down the Earth.... so might directing as asteroid to hit us

[Miguelito Loveless]

4. So,

we are installing billions of solar panels so we fan degrade their output?

[Xoan]

5. Idiocracy isn't just for kids.