Proxima b: New planet, new hopes, huge distances
In a desperate attempt to overcome our cosmic solitude, the human beings sift through the data collected from the immensity of the space to detect the slightest possible evidence of a life like the one on the Earth, and eavesdrop on the faintest radio signals transmitted from the supposed alien civilizations from the deep space. Once a planet, roughly like our cosmic home, is found somewhere in the cosmos, a wave of joy runs through our souls, making us feel that our loneliness in the incomprehensible universe is finally eased.
Quite recently, a team of astronomers found a planet, which revolves its host star, Proxima Centauri – a dim red dwarf star and part of a three-star system, Alpha Centauri – every 11 Erath’s days, and which is at least 1.3 times the mass of our home planet.
We have so far discovered, particularly by NASA’s Kepler planet-finding mission, a bounty of Earth-size planets throughout the Milky Way, but the newly discovered world, called Proxima b, holds a particular promise, since it is only 4.2 light years away from us, or 266,000 times the distance between the Earth and our Sun.
Astronomically speaking, Proxima b, then, is considered a close neighbor, unlike the previously found worlds. But how much close is it? Can we go there for a rainy day?
If you travel at the speed of light, some 300,000 kilometers per second (186,000 miles per second), you will reach it in a four years’ time, but if you set off with our current state of the art propulsion system, the journey can take some several tens of thousands of years to complete.
The new exoplanet also has another advantage: it lies within the habitable zone, so it probably has liquid water on its surface, a key ingredient to life as it is known on Earth.
The habitable zone by definition is the area around a star where rocky planets have surfaces warm enough, with sufficient atmospheric pressure, to keep water in its liquid form.
“It’s not only the closest terrestrial planet found, it’s probably the closest planet outside our solar system that will ever be found because there is no star closer to the solar system than this one,” said lead study author of the discovery, Guillem Anglada-Escudé.
Astronomers, however, hope that in the coming decades we can receive some more data and direct and close snapshots from Proxima b. But how?
Back in April, Russian Internet entrepreneur and space enthusiast billionaire Yuri Milner, the founder and funder of the Breakthrough Initiatives, together with renowned British cosmologist Stephen Hawking announced one of the most ambitious projects ever to detect extraterrestrial intelligence in the vicinity of the Alpha Centauri.
The Breakthrough Starshot is simple at the first glance. Thousands of ultra-light wafer-size chips attached to super-thin light sails will be launched to space by a mothership. The tiny probes will then be pushed towards the star system by powerful laser beams shot from the Earth, which make the craft accelerate up to 20 percent the speed of light, some 60,000 kilometers (37,000 miles) per second.
It will take some 20 years for the fleet to reach the star system and begin taking images of its planets and then send them back home, which takes another four years. It would take a conventionally propelled probe about 30,000 years to make such a voyage, which is far beyond humans’ brief lifetimes.
“Over the next decade, we will work with experts here at ESO and elsewhere to get as much information as possible about the Proxima Centauri planet, perhaps as noted, even including whether it might bear life, prior to launching mankind’s first probe towards the star,” said Pete Worden, Chairman of the Breakthrough Prize Foundation, on Wednesday. “We also hope to obtain similar data about the other nearby stars, Alpha Centauri A and B.”