Astrophysicists show how to deflect solar radiation in an unexpected
method.
Louis XIV, the longest-reigning king in French history, was known as "the
Sun King" or "le Roi Soleil" due to his astonishing passion for dance. The
star at the core of our solar system was unrelated to it. But oddly enough,
the sun started behaving oddly throughout Louis XIV's reign.
Around 1645, it underwent a behavioral shift. Sunspots become quite
uncommon. No sunspots were found at all in certain years. The power of the
sun waned. The Maunder Minimum, which took place during a "Little Ice Age,"
was accompanied by an
especially cold episode in the North Atlantic around 1650.
Things are moving in the other way right now.
While the energy of the sun has remained mostly unchanged, the Earth is warming. The combustion of fossil fuels, which releases
carbon dioxide into the atmosphere and traps heat, is the main cause of this
rise in temperature. Temperatures are predicted to increase by more than 1.5
degrees Celsius over preindustrial levels in the next decades if CO2
emissions are not rapidly reduced. Temperature rises of more than 2 or even
3 degrees are possible in the worst-case circumstances.
Why not dull the sun? has been proposed as a contentious technological
remedy in recent years. One of the most contentious theories for this
process, known as solar geoengineering, proposes shooting sulfur particles
into the atmosphere in a manner that resembles the explosion of volcanoes.
The sun's beams would then be reflected back into space by the reflecting
particles.
Due to the fact that it doesn't address the fundamental cause of climate
change and the possible repercussions are not completely known, scientists
and experts aren't yet sure that even attempting it is a smart idea. There
is a non-zero chance that altering the atmosphere might lead to permanent
consequences we haven't thought about and are ill-prepared for. It could
also lead us to think that there is a solution to stop climate change
without cutting back on carbon output. No, spoiler alert.
But what if we dropped the same particles into space rather than the
atmosphere? If we tried some astroengineering, what would happen?
Three scientists examine potential ways to accomplish this by releasing
reflecting dust particles into space in a new report that was
published in the journal PLOS Climate
on Wednesday. The scientists used computer simulations to determine that one
option is to employ moon dust, shoot it into space from the lunar surface,
and temporarily obscure our light.
The paper's first author, University of Utah theoretical astrophysicist
Benjamin Bromley, emphasizes that the group's goal was not to provide a
solution to the climate problem and that they are not climate experts. His
primary area of study is the formation of planets, and Scott Kenyon of the
Smithsonian Astrophysical Observatory, computer science student Sameer Khan,
and he found inspiration in this process.
Because collisions create planets, Bromley explained, "we learnt from that
research that a relatively modest quantity of dust may go a great way in
absorbing starlight." "That made us consider dust as a means of reducing the
sun's radiance."
According to Bromley, the idea would be similar to the situation that
existed during Louis XIV's rule in France during the Little Ice Age. It
would take a lot of dust, but if you could get it into space, it would
effectively work to block 1% to 2% of the light, reducing solar
energy.
A station that spews space dust out at the Lagrange point L1, which is
located 900,000 miles within the Earth's orbit and directly between the sun
and the Earth, was one of the team's initial concepts. At this point,
gravity from the two bodies has a way of holding everything in place. (In
fact, the James Webb Space Telescope is located at the opposite Lagrange
point, L2, which is outside of Earth's orbit.)
In the simulations, the dust would soon drift away from the L1 location,
which was an issue. The surface wasn't solid enough to support a dust
barrier.
They turned their attention to something a little closer to their location:
the moon. They created simulations that showed the most effective plan was
to fire lunar grains from the moon toward L1.
Two things made lunar dust stand out, according to Bromley First of all, it
may be rather effective at reflecting sunlight, and secondly, it turns out
that the most effective grain size is also the one that is most prevalent on
the surface of the moon.
He adds that this was a pleasant discovery that they were unaware of before
the project began. However, one of the issues is how much dust is necessary.
A second benefit of the moon is that it would be prohibitively expensive to
continuously launch rockets filled with space dust to a platform out at
L1.
The moon has a lesser gravity than Earth, so launching the dust from there
will be lot simpler if we can get the equipment there, according to
Bromley.
But what occurs once the dust is in space? The models, fortunately,
indicated that the dust particles didn't actually rain back down on Earth.
Instead, they would float away from the sun as they traveled into the
endless night.
The proposal from the trio is not the first for a solar shield built in
orbit.
Curtis Struck of Iowa State University proposed a similar idea to employ moon dust in 2007.
A group of MIT researchers
put up the concept of "space bubbles" last year. To deflect oncoming
sunlight, the plan is to launch a raft of bubbles into low-Earth orbit (L1).
This would be a reversible procedure.
However, none of these strategies will be adopted rapidly enough to stop
the present rise in temperature. However, we could have to resort to a
"break glass in case of emergency" strategy if we set the Earth on an
unstoppable course toward becoming a hothouse. Moon dust can be added to the
list.
Despite the technical difficulties, Bromley believes that lunar dust should
be investigated as a possibility if we reach a position when darkening the
sun is a necessary step.
