2024-09-17 22:06:03
Everything indicates that the only technologically viable way today to reach a planet in another solar system before the end of the century is by means of a laser-powered light sail from Earth or its immediate vicinity, and sending there a swarm of ships weighing only a few grams each.
Several theoretical designs are already in the works, and another was recently presented, the result of research conducted by Thomas Eubanks of Space Initiatives, Inc. in the United States. The design has sparked the interest of NASA.
Eubanks and his colleagues expect that by mid-century, technology will be available that can emit laser beams powerful enough (about 100 gigawatts) to propel gram-weight laser-sail-equipped spacecraft from afar, accelerating them to close enough to the speed of light that the journey will take only a few years, not decades or centuries. At that speed, the ships will experience relativistic effects.
Laser sails will need to be robust enough to survive launch from Earth’s surface. Light cubes large enough (at least 1 square kilometer) to pick up the swarm’s optical signals when it is far away will also need to be installed on areas of Earth’s surface.
If all this is achieved, the mission proposed by Space Initiatives will be feasible.
The mission would not be launched before 2075, but certainly before the end of this century. It would involve flying by Proxima b, a potentially habitable planet orbiting the closest star to Earth after the Sun, Proxima Centauri. The mission would be carried out by a large autonomous swarm of thousands of tiny space probes.
Given the extreme limitations of launch mass (a few grams for each craft), onboard power (milliwatts), and communications aperture (centimeters to meters), the research team has determined that only a large swarm of many probes acting in unison can generate an optical signal powerful enough to traverse the immense distance from the swarm’s location in another solar system to Earth.
By: NCYT