According to researchers, it would be possible to prevent part of the sun’s rays from reaching Earth by throwing dust between the two stars.
Since the middle of the last century, human activity has taken on such proportions that it considerably modifies the climate of the entire planet. Changing the practices of a civilization numbering billions of people is a daunting task, and there seems not enough time left before we reach a point of no return. It thus appears that climate change and its consequences will be part of our future.
A parasol to protect the Earth
Geoengineering is a set of techniques that aim to modify the climate of a planet. Ironically, our greenhouse gas emissions could be considered one such technique. Thus, thinkers, researchers and industrialists are trying to imagine and develop large-scale solutions to counter global warming, such as carbon capture.
The greenhouse effect works like a blanket that traps part of the solar radiation received by the Earth. One of the strategies to reduce its impact, if it is too great, would be to block some of the rays before they reach our atmosphere. The concepts are numerous, but they often involve the use of huge structures in space, much like deploying a parasol in orbit. These would involve considerable manufacturing, installation and maintenance costs, which would perhaps only be conceivable in a future where the exploitation of space resources would have already begun a few decades ago.
Researchers at the University of Utah wanted to study another technique to give us ” a little more shade » : send huge amounts of dust to the Lagrange point L1 between the Earth and the Sun. This point of gravitational equilibrium between the two stars allows objects to remain in a stable orbit, generally without deviating from it. If a cloud of dust placed there had the possibility of blocking a significant part of the sun’s rays for a sufficiently long time, it would not however remain indefinitely in place.
Advantages in the disadvantages
“Heavy” objects, such as the James Webb telescope, can anchor themselves in their orbits for a very long time without the need for readjustment. But, the dust is more exposed to factors other than gravity, such as solar winds or various radiations. A shield that would be made up of it would thus be doomed to be dispersed quickly. It would then have to be fed permanently, which would imply constant maintenance and the need for a significant source of supply.
This is why the study finally focused on lunar dust. Indeed, if it has the appropriate characteristics to block the sun’s rays, it would also be easy to transport it to the Lagrange point L1. Since gravity is weaker on the Moon than on Earth, it would be possible to continuously power the shield while consuming relatively little fuel, or any other energy source. This solution is considered by the study to be the most viable, as it would benefit from a sufficient stock of dust and would not require platforms in orbit, as would be the case for transport from Earth.
The authors point out that the advantage of using dust lies precisely in its ability to dissipate quickly. Thus, the solar shield would remain the necessary time, and the particles should not fall on the Earth. Nevertheless, they point out that their study only explores the impact of such a strategy: We are not experts in climate change or the rocket science needed to move mass from one place to another. We’re just exploring different types of dust in various orbits to see how effective this approach might be. »
Source : ScienceDaily
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