Scientists have long known that the Sun will not shine forever. In roughly five billion years, it is expected to exhaust its hydrogen fuel, expand into a Red Giant, and dramatically reshape the Solar System. Mercury and Venus will almost certainly be consumed, while Earth’s fate remains uncertain—many models suggest our planet could also be engulfed or rendered completely uninhabitable.
Now, a new study argues that humanity might not have to accept that future. An upcoming paper by independent researcher Gabriel Harry, set to be published in the Journal of the British Interplanetary Society, outlines an extraordinary series of megaengineering projects that could theoretically keep Earth habitable for far longer than previously imagined.
A Survival Plan That Spans Quadrillions of Years
Harry’s proposal goes far beyond protecting Earth from the Sun’s eventual expansion. According to the study, a sufficiently advanced civilization could safeguard the planet against multiple existential threats, including:
- The Sun’s increasing brightness and eventual death
- Plate tectonic changes
- Loss of Earth’s water
- Changes in the planet’s tilt and rotation
- Asteroid and comet impacts
- Other long-term cosmic hazards
The paper estimates that implementing these safeguards could allow Earth to remain habitable for approximately 9.1 million billion years—or about 9.1 quadrillion years—far beyond the natural lifespan of the Sun.
While the proposal is theoretical, it offers a fascinating glimpse into what future civilizations might attempt if technological limitations continue to shrink over astronomical timescales.
A Giant Sunshield Around Earth
One of the study’s central ideas is the construction of an enormous sunshield designed to block the increasing solar radiation as the Sun grows brighter.
Harry proposes a shield approximately 700,000 kilometers wide, positioned just beyond the Moon’s orbit. The structure would reduce the amount of sunlight reaching Earth, preventing runaway global heating as the Sun ages.
How Would It Stay in Place?
Keeping such a massive structure stable would require equally ambitious engineering.
According to the proposal:
- A 2-million-kilometer carbon tether would anchor the shield.
- The tether would connect to a counterweight located at the Sun-Earth Lagrange Point 1 (L1), where gravitational forces help maintain a stable position.
- The shield itself would be manufactured primarily from aluminum mined from the Moon.
- Despite being only 0.1 millimeters thick, the shield would have an estimated mass of around 100 quadrillion kilograms.
Perhaps the most astonishing claim is the source of the tether material. Harry suggests mining roughly 40% of the dwarf planet Ceres to obtain enough carbon.
Blocking the Sun Creates Another Problem
A permanent sunshade would solve one problem while creating another.
If Earth receives significantly less sunlight, global temperatures would plunge, eventually freezing the planet.
To compensate, Harry proposes creating an artificial Sun.
An Artificial Sun Powered by Jupiter
Instead of relying on natural sunlight, the study envisions using fusion reactors fueled by material extracted from Jupiter.
The concept involves:
- Positioning fusion reactors roughly 6,500 kilometers inside Jupiter’s atmosphere
- Harvesting fuel from the gas giant
- Converting that fuel into energy through nuclear fusion
- Beaming the generated energy to Jupiter’s L1 point
- Redirecting that energy toward Earth to provide controlled heating
The artificial illumination would replace the sunlight blocked by the giant shield, theoretically allowing Earth to maintain habitable temperatures.
Although today’s technology is nowhere near capable of such feats, the proposal assumes engineering capabilities many millions—or even billions—of years more advanced than our own.
Moving Earth Away From the Dying Sun
Even with a sunshield and artificial heating, another challenge remains.
As the Sun expands into a Red Giant, its outer atmosphere could eventually reach Earth’s orbit.
To avoid being swallowed, Harry suggests gradually moving Earth’s orbit farther from the Sun.
The proposal calls for shifting Earth from its current distance of 1 astronomical unit (AU) to approximately 1.2 AU.
How Could an Entire Planet Be Moved?
The study proposes using a continuous particle beam generated with oxygen mined from Jupiter.
By directing the beam past Earth over an extremely long period, it would impart a tiny but continuous gravitational and momentum-based push.
The amount of oxygen required would be roughly equivalent to half the annual outflow of the Amazon River, according to the paper.
Although the force would be incredibly small, acting over millions of years it could theoretically move Earth’s orbit outward enough to escape the expanding Sun.
Science Fiction—or Far-Future Engineering?
At first glance, the proposal sounds more like the plot of a science fiction novel than a practical scientific roadmap.
Mining nearly half of Ceres, building a two-million-kilometer tether, harvesting Jupiter for fusion fuel, and nudging an entire planet into a new orbit are engineering challenges far beyond anything humanity can currently accomplish.
However, that does not necessarily make the ideas scientifically meaningless.
Many concepts once considered impossible—from satellites and reusable rockets to gravitational-wave detection—eventually became reality as technology advanced. The study is less about today’s engineering limits than about exploring what the laws of physics might permit for a civilization with billions of years to prepare.
What Scientists Already Agree On
While Harry’s proposal is highly speculative, the broader timeline of the Sun’s evolution is well established.
Astronomers expect that:
- The Sun will continue brightening over the next billion years, making Earth increasingly difficult to inhabit.
- In about five billion years, it will exhaust its core hydrogen and expand into a Red Giant.
- Eventually, it will shed its outer layers and leave behind a dense white dwarf, surrounded by a glowing planetary nebula.
The exact fate of Earth during the Red Giant phase remains an active area of research. Some models predict the planet will be engulfed, while others suggest it could survive physically but become completely uninhabitable.
A Thought Experiment for the Distant Future
Harry’s study is best viewed as a long-term thought experiment rather than a blueprint for immediate action. It explores how an unimaginably advanced civilization might preserve Earth’s habitability across cosmic timescales by combining planetary engineering, orbital mechanics, and large-scale energy management.
Whether any of these ideas could ever be realized remains uncertain. For now, they serve as a reminder that humanity’s future—if civilization endures long enough—may depend not only on understanding the universe, but also on learning how to reshape it.