The goal of sending a probe to the nearest star system, where a second planet has just been discovered, continues. Students and researchers from the Starlight project at the University of California have tested in the stratosphere what could become an interplanetary probe. To make it a reality, this project will require technological leaps and find hundreds of billions of dollars to fund it.
Of all the interstellar probe projects for the Proxima Centaur star, located just 4.2 light-years away from Earth, the Starlight program of the University of California supported by NASA and the Breakthrough Initiatives Foundation is the most interesting, as it intends to send a probe there in just 20 years. An astonishing journey when we know that a chemical-propelled spacecraft, such as the one that took us to the moon almost 50 years ago, would need 100,000 years to achieve it.
Alpha Centauri is a system composed of three stars. Alpha Centauri A and Alpha Centauri B are its main components, forming a double star. As for the third, Alpha Centauri C, also called Proxima Centauri, is a red dwarf less bright, and best known as the star nearest the sun. This system houses at least one planet, which revolves around Alpha Centauri B. Provisionally named Alpha Centauri Bb, it is a rocky planet. But at the conference Breakthrough Discuss held on 11 and 12 April in California, the detection of a possible second exoplanet has been announced.
A journey of a few decades rather than millennia
The idea is to use a photonic sail pulling a tiny probe of a few grams at most. This sail will be propelled by laser beams sent from the Earth. This use of light, as a propulsion system, is the only way to reach the neighboring stars on the scale of human life. That said, given the distance we are talking about, still 40,000 billion kilometers, and the fact that the probe will have to reach about 20% of the speed of light when our current probes do not exceed 0.01 %, the realization of this Earth-based laser is the biggest challenge of the project.
A few days ago, the project team successfully tested a prototype of the probe that could make this interstellar journey. This test consisted of sending a very precursor prototype of an interplanetary probe, by balloon, to more than 32,000 meters in the stratosphere. The goal was to test the functionality and performance of this lilliputian “satellite”. Building on the progress of miniaturization, all the elements necessary for an exploration mission such as cameras, detectors, navigation system and communication equipment will be installed on this probe the size of a human hand. The next step is a suborbital flight planned next year.
Rather than creating a single probe, the team hopes that their research will lead to the creation of hundreds or even thousands of these ships that can visit exoplanets in nearby star systems. Ultimately, the development of this technology will pave the way for a variety of missions that would have been considered too costly or impossible to achieve with conventional chemical propulsion technology. In addition to these interstellar journeys, this technology could facilitate fast, inexpensive exploration missions to Mars and other parts of the Solar System.