A new space telescope mission unveiled today (Nov. 16) will look for habitable planets in the Alpha Centauri system, our sun's closest stellar neighbors.
The new mission, called TOLIMAN after an ancient Arabic-derived name for Alpha Centauri, will carry a novel telescope fitted with a so-called diffractive pupil lens that spreads starlight into a flowerlike pattern. This unique lens will make it easier for astronomers using the scope to detect tiny irregularities in a stars' movements that are usually caused by the gravitational influence of orbiting planets, according to a statement by Breakthrough Initiatives, which is backing the mission.
"Even for the very nearest bright stars in the night sky, finding planets is a huge technological challenge," Eduardo Bendek, an optical engineer at NASA's Jet Propulsion Laboratory, a collaborator on the mission, said in the statement.
"Our TOLIMAN mission will launch a custom-designed space telescope that makes extremely fine measurements of the position of the star in the sky. If there is a planet orbiting the star, it will tug on the star betraying a tiny, but measurable, wobble," Bendek said.
Alpha Centauri is the closest solar system to Earth and it has three stars, two of which are like our sun. The third star is a red dwarf called Proxima Centauri, a cool but long-lived type of a star that is the most common in the universe.
This red dwarf is known to have at least two exoplanets, one of which appears to be fairly similar to Earth.
But so far, this intriguing star system, just four light-years away from us, has avoided detailed scientific scrutiny, despite the fact that the planets around these stars could present the most convenient destination for humankind outside of our own solar system.
While, for now, a human mission to Alpha Centauri remains in the realm of science fiction, the TOLIMAN telescope will at least attempt to answer some of the most fundamental and pressing questions about its planets. Most importantly, scientists hope to use the new scope to investigate whether these far-off worlds might indeed harbor life, or perhaps provide the right conditions for its survival.
"Our nearest stellar neighbors — the Alpha Centauri and Proxima Centauri systems — are turning out to be extraordinarily interesting," Pete Worden, executive director of the Breakthrough Initiatives, said in the statement. "The TOLIMAN mission will be a huge step toward finding out if planets capable of supporting life exist there."
The mission will focus on the habitable zone around the system's three stars, a region of space in the star's vicinity where liquid water could exist.
"These nearby planets are where humanity will take our first steps into interstellar space using high-speed, futuristic, robotic probes," Pete Klupar, chief engineer of Breakthrough Watch, a branch of Breakthrough Initiatives, said in the statement. "If we consider the nearest few dozen stars, we expect a handful of rocky planets like Earth orbiting at the right distance for liquid surface water to be possible."
Professor Peter Tuthill of the Sydney Institute for Astronomy, who leads the development of the mission, added that TOLIMAN will begin answering the questions about the nature of these intriguing worlds.
"Getting to know our planetary neighbors is hugely important," Professor Tuthill said. "These next-door planets are the ones where we have the best prospects for finding and analyzing atmospheres, surface chemistry and possibly even the fingerprints of a biosphere — the tentative signals of life."
The team, which also includes experts from Australian space-tech firm Saber Astronautics, began working on the mission in April this year, according to the statement.
The mission received $788,000 ($576,000) from the Australian government and is expected to be ready for science in the mid-2020s.
"Our plan is for an agile low-cost mission that delivers results by about the middle of the decade," Tuthill said.