Solar Gravitational Lensing for Power Transmission: Can We Use Sun’s Gravity To Communicate Between Stars?

Einstein's Theory of General Relativity has reshaped our understanding of the universe and predicted events that continue challenging the scientific community. Among these predictions was gravitational lensing, which bends the gravity of massive celestial objects to turn light.

Several decades after gravitational lensing was observed, Slava G. Turyshev of NASA's Jet Propulsion Laboratory has decided to pioneer this concept in new realms. He investigated the potential of the Sun as a cosmic lens for observing the universe and fueling our interstellar endeavors. In his study "Gravitational lensing for interstellar power transmission," Turyshev presents a plan for exploiting Solar Gravity Lenses (SGLs) to transmit energy between stars.

What is Solar Gravitational Lensing?

Solar Gravitational Lens refers to a phenomenon that occurs when the Sun's gravitational field bends and focuses light from a distant object, like a star or galaxy. This bending effect is similar to how a lens can focus light to a point.

As a massive celestial body, the Sun creates a warp in spacetime where it curves the paths of passing photons towards its center. When these paths align correctly with an observer, the light from distant objects is magnified and intensified. This allows for detailed observation, which would be impossible with current technology due to the vast distances of space.

Sun as a Cosmic Lens

Astronomers have discovered other applications for SGLs. By placing a transmitter at an SGL's focal region, focusing light beams using the Sun's gravity would enable power transmission across the universe. This system can amplify faint signals from distant objects and, at the same time, serve as a means of high-resolution observation.

In previous studies, Turyshev and his colleague, Carleton University Senior Research Fellow Viktor Toth, have investigated the properties of gravitational lenses. They also studied the potential of a spacecraft located in the focal region of an SGL in facilitating advanced astronomical research. This potential includes the ability of an SGL to amplify light from faint distant objects like exoplanets to a degree where the resolution is equivalent to observations made from high orbit.

Turyshev's current research builds on these foundations, allowing him to investigate using a star's gravitational field to transmit focused energy. Turyshev proposes methods to boost light using one or two lens systems in his study. He came up with three methods to send laser energy through space. Each technique involves placing a laser transmitter at a specific point near a lens where it can send a stronger signal to a distant receiver.

The research reveals that the signal-to-noise ratio of the transmitted signal would be higher with this configuration because the lenses boosted light. If viable, this power transmission strategy can herald a new era of space exploration. By allowing the beaming of power between star systems, humans can sustain long-duration missions in deep space and lay the groundwork for interstellar colonization.

Realizing this vision will still face many logistical complexities. The alignment of transmitters and receivers across stellar distances requires precision engineering and navigation, which are yet to be achieved. Aside from this, other gravitational fields along the transmission path can also bend and weaken the signal. Despite these challenges, gravitational lensing could be a potential platform for allowing communication, observation, and power transmission across interstellar distances.