Tiny Swarming Spacecraft Could Establish Communications with Proxima Centauri

Swarm of laser-sail spacecraft leaving the solar system. Credit: Adrian Mann

Achieving interstellar travel has been the dream of countless generations, but the challenges remain monumental. Aside from the vast distances involved, there are also the prohibitive energy requirements and the sheer cost of assembling spacecraft that could survive the trip. Right now, the best bet for achieving an interstellar mission within a reasonable timeframe (i.e., a single person’s lifetime) is to build gram-scale spacecraft paired with lightsails. Using high-power laser arrays, these spacecraft could be accelerated to a fraction of the speed of light (relativistic speeds) and reach nearby stars in a few decades.

There are a handful of major projects, like Breakthrough Starshot, that hope to leverage this technology to create spacecraft that could reach Alpha Centauri in a few decades (instead of centuries). This technology also presents other opportunities, like facilitating communications across interstellar distances. This is the idea recently by a team of researchers led by the Initiative for Interstellar Studies (i4is). In a recent paper, they recommended that a swarm of gram-scale spacecraft could rely on their launch laser to maintain optical communications with Earth.

Continue reading “Tiny Swarming Spacecraft Could Establish Communications with Proxima Centauri”

A New Mission Will Search for Habitable Planets at Alpha Centauri

Artist's impression of a hypothetical planet orbiting the star Alpha Centauri B, a member of the triple star system that is the closest to Earth. Credit: ESO

Alpha Centauri is our closest stellar neighbor, a binary star system located just 4.376 light-years away. Despite its proximity, repeated astronomical surveys have failed to find hard evidence of extrasolar planets in this system. Part of the problem is that the system consists of two stars orbiting each other, which makes detecting exoplanets through the two most popular methods very challenging. In 2019, Breakthrough Initiatives announced they were backing a new project to find exoplanets next door – the Telescope for Orbit Locus Interferometric Monitoring of our Astronomical Neighbourhood (TOLIMAN, after the star’s ancient name in Arabic).

This low-cost mission concept was designed by a team from the University of Sydney, Australia, and aims to look for potentially-habitable exoplanets in the Alpha Centauri system using the Astrometry Method. This consists of monitoring a star’s apparent position in the sky for signs of wobble, indicating that gravitational forces (like planets) are acting on it. Recently, the University of Sydney signed a contract with EnduroSat, a leading microsatellites and space services provider, to provide the delivery system and custom-built minisatellite that will support the mission when it launches.

Continue reading “A New Mission Will Search for Habitable Planets at Alpha Centauri”

A THIRD Planet Found Orbiting Nearby Proxima Centauri

This artist’s impression shows Proxima d, a planet candidate recently found orbiting the red dwarf star Proxima Centauri, the closest star to the Solar System. The planet is believed to be rocky and to have a mass about a quarter that of Earth. Two other planets known to orbit Proxima Centauri are visible in the image too: Proxima b, a planet with about the same mass as Earth that orbits the star every 11 days and is within the habitable zone, and candidate Proxima c, which is on a longer five-year orbit around the star.

In August of 2016, astronomers with the European Southern Observatory (ESO) announced that they had discovered an exoplanet orbiting in neighboring Proxima Centauri. Based on Radial Velocity measurements (aka. Doppler Photometry), the discovery team estimated that the planet was roughly the same size and mass as Earth and orbited with Proxima Centauri’s Circumsolar Habitable Zone (HZ). In 2020, this planet was confirmed by follow-up observations.

In that same year, a second exoplanet (Proxima c) roughly seven times the mass of Earth (a Super-Earth or mini-Neptune) was confirmed. As if that wasn’t enough, an international team of astronomers with the ESO recently announced that they detected a third exoplanet around Proxima Centauri – Proxima d! This Mars-sized planet orbits about halfway between its host star and Proxima b and is one of the lightest exoplanets ever discovered.

Continue reading “A THIRD Planet Found Orbiting Nearby Proxima Centauri”

A Space Telescope With one job: Find Habitable Planets at Alpha Centauri

Artist's impression of a hypothetical planet orbiting the star Alpha Centauri B, a member of the triple star system that is the closest to Earth. Credit: ESO

Alpha Centauri, the nearest star system to our Sun, is like a treasure trove with many scientific discoveries just waiting to be found. Part of what makes it so compelling is that our efforts to detect extrasolar planets there have failed to yield any concrete results to date. While the study of exoplanets has progressed exponentially in recent years, with 4,575 confirmed planets in 3,392 systems in the Milky Way (and even neighboring galaxies), astronomers are still having difficulty determining if anyone is next door.

In the coming decades, Breakthrough Initiatives plans to send a mission there known as Starshot, a lightsail craft that could make the journey in 20 years. On Nov. 16th, Breakthrough Initiatives announced another project for detecting exoplanets next door. It’s called the Telescope for Orbit Locus Interferometric Monitoring of our Astronomical Neighbourhood (TOLIMAN), a space telescope dedicated to finding rocky planets orbiting in Alpha Centauri’s circumsolar habitable zone (aka. “Goldilocks Zone”).

Continue reading “A Space Telescope With one job: Find Habitable Planets at Alpha Centauri”

Maybe There’s No Way to Tell if Habitable Planets Orbit Proxima Centauri… Yet!

This artist’s impression shows the planet Proxima b orbiting the red dwarf star Proxima Centauri, the closest star to the Solar System. The double star Alpha Centauri AB also appears in the image between the planet and Proxima itself. Proxima b is a little more massive than the Earth and orbits in the habitable zone around Proxima Centauri, where the temperature is suitable for liquid water to exist on its surface. Credit: ESO/M. Kornmesser

Our closest stellar neighbor is Proxima Centauri, an M-type (red dwarf) star located over 4.24 light-years away (part of the Alpha Centauri trinary system). In 2016, the astronomical community was astounded to learn that an Earth-like planet orbited within this star’s circumsolar habitable zone (HZ). In addition to being the closest exoplanet to Earth, Proxima b was also considered the most promising place to look for extraterrestrial life for a time.

Unfortunately, the scientific community has been divided on whether or not life could even be possible on this planet. All of these studies indicate that this question cannot be answered until astronomers characterize Proxima b’s atmosphere, ideally by observing it as it passes in front (aka. transited) of its host star. But in a new NASA-supported study, a team led by astrophysicists at the University of Chicago determined that this is an unlikely possibility.

Continue reading “Maybe There’s No Way to Tell if Habitable Planets Orbit Proxima Centauri… Yet!”

The Radio Signal From Proxima Centauri Came From Earth After All

The three telescopes at CSIRO’s Parkes Observatory. Credit: Red Empire Media/CSIRO.

Turns out we were hearing ourselves! Earth can be a noisy place when listening to stars.

Late last year, a story was leaked indicating that the Murriyang radio telescope in Australia had detected a “signal-of-interest”. Dubbed “blc1” (Breakthrough Listen Candidate 1), the signal appeared to originate from the direction of Proxima Centauri, the closest neighbouring star to the Sun. The signal had yet to be fully analyzed when the story was leaked. Now that the analysis is complete, research shows blc1 is in fact “RFI” – radio frequency interference – and not an interstellar signal.

But while it’s not aliens – or “Proxima Centaurians” as lead author on the signal analysis Dr. Sofia Sheikh whimsically refers to them – new methodologies for conducting radio-based SETI (Search for Extraterrestrial Intelligence) have been developed by analyzing blc1; further honing our ability to distinguish future potential ET signals from our own planet.

Simulation of Proxima Centauri b , Rocky World in the Proxima Centauri System – SpaceEngine by author
Continue reading “The Radio Signal From Proxima Centauri Came From Earth After All”

What Would It Take To See Artificial Lights at Proxima Centauri B?

Feature Image Description: Ecumenopolis Planet orbiting Proxima Centauri-like Red Dwarf Star - Graphics from the video game Stellaris, developed and published by Paradox Interactive. - used with permission

Is there an alien civilization next door? It’s…possible(ish). In late 2020, we discovered a signal from the direction of Proxima Centauri (not necessarily from Proxima Centauri), our closest neighbour star. Named BLC- 1 by project Break Through Listen, the signal is still being analyzed to ensure it isn’t simply an echo of our own civilization – typically what they turn out to be. But why not just directly look at planets in Proxima Centauri and see if a civilization is there?

From space, the most obvious sign somebody lives on Earth is the glow from the nightside of our planet. Our cities emit light that’s shed into the Cosmos. Problem is that our current generation of telescopes are not powerful enough to see lights on distant worlds. But several researchers are testing the capabilities of the next generation of telescopes already on the drawing board. The finding? Yes! if advanced enough…or glowy enough…we would be able to see if another civilization has the lights on at Proxima Centauri.

8k compilation of footage taken from the International Space Station orbiting above Earth’s City Lights
Continue reading “What Would It Take To See Artificial Lights at Proxima Centauri B?”

A Recent Megaflare Shows that Proxima Centauri is not a Nice Place to Live

An artist's conception of a violent flare erupting from the red dwarf star Proxima Centauri. Such flares can obliterate atmospheres of nearby planets. Credit: NRAO/S. Dagnello.
An artist's conception of a violent flare erupting from the red dwarf star Proxima Centauri. Such flares can obliterate atmospheres of nearby planets. Credit: NRAO/S. Dagnello.

Proxima b, the closest exoplanet to our Solar System, has been a focal point of scientific study since it was first confirmed (in 2016). This terrestrial planet (aka. rocky) orbits Proxima Centauri, an M-type (red dwarf) star located 4.2 light-years beyond our Solar System – and is a part of the Alpha Centauri system. In addition to its proximity and rocky composition, it is also located within its parent star’s habitable zone (HZ).

Until a mission can be sent to this planet (such as Breakthrough Starshot), astrobiologists are forced to postulate about the possibility that life could exist there. Unfortunately, an international campaign that monitored Proxima Centauri for months using nine space- and ground-based telescopes recently spotted an extreme flare coming from the star, one which would have rendered Proxima b uninhabitable.

Continue reading “A Recent Megaflare Shows that Proxima Centauri is not a Nice Place to Live”

A Review of “Extraterrestrial” by Prof. Avi Loeb

Credit: Houghton Mifflin Harcourt

On October 19th, 2017, astronomers from the Haleakala Observatory in Hawaii announced the first-ever detection of an interstellar object in our Solar System. In honor of the observatory that first spotted it, this object (designated 1I/2017 U1) was officially named ‘Oumuamua by the IAU – a Hawaiian term loosely translated as “Scout” (or, “a messenger from afar arriving first.”)

Multiple follow-up observations were made as ‘Oumuamua left our Solar System and countless research studies resulted. For the most part, these studies addressed the mystery of what ‘Oumuamua truly was: a comet, an asteroid, or something else entirely? Into this debate, Dr. Shmuel Bialy and Prof. Avi Loeb of the Harvard Institute for Theory and Computation (ITC) argued that ‘Oumuamua could have been an extraterrestrial probe!

Having spent the past few years presenting this controversial theory before the scientific and astronomical community, Prof. Loeb has since shared the story of how he came to it in his new book, Extraterrestrial: The First Sign of Intelligent Life Beyond Earth. The book is a seminal read, addresses the mystery of ‘Oumuamua, and (most importantly) urges readers to take seriously the possibility that an extraterrestrial encounter took place

Continue reading “A Review of “Extraterrestrial” by Prof. Avi Loeb”

According to the Math, it’s Highly Unlikely That an Intelligent Civilization is Located at Alpha Centauri

The Parkes radio telescope at Parkes Observatory in New South Wales, Australia. Astronomers using the telescope detected what appeared to be a radio signal coming from the direction of Proxima Centauri in April and May 2019. Image via Daniel John Reardon/ Wikimedia Commons.

In December of 2020, the world got a bit of a pre-holiday surprise when it was announced that astronomers at the Parkes radio telescope in Australia had detected a “tantalizing” signal coming from Proxima Centauri (the red dwarf companion of the Alpha Centauri system). Afterward, researchers at Breakthrough Listen consulted the data on the signal – Breakthrough Listen Candidate 1 (BLC1) – and noted the same curious features.

However, the scientific community has since announced that the signal is unlikely to be anything other than the result of natural phenomena. This was also the conclusion reached by Amir Siraj and Prof. Abraham Loeb of Harvard University after they conducted a probability assessment on BLC1. Like the vast majority of candidate radio signals discovered to date, this one appears to be just the forces of nature saying hello.

Continue reading “According to the Math, it’s Highly Unlikely That an Intelligent Civilization is Located at Alpha Centauri”