Exoplanets Archives

April 23, 2021April 23, 2021 by Matt Williams

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.

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.

April 22, 2021April 22, 2021 by Andy Tomaswick

Giant Planet is Found at an Extreme Distance From its Star

One of the best things about the sheer number of exoplanets that astronomers are currently finding is how some are just very different. Those differences can sometimes undermine standing theories, and prompt scientists to start considering new theories that account for the new information. That is undoubtedly what will happen to accommodate a new massive planet found by a team led by Dutch scientists. This planet is unique in one very special way – it is about 110 times farther away from its star than the Earth is from the sun.

April 14, 2021April 14, 2021 by Brian Koberlein

Finding Oxygen on an Alien World Doesn't Always Mean There's Life There

Artist concept of the planetary system Kepler 62. Credit: Danielle Futselaar - SETI Institute

We now know the universe is filled with planets. By one estimate, there are more than 20 billion Earth-like worlds in our galaxy alone. But how many of them are likely to have life? And how would we know if they do? Unless they happen to send us a very clear message directly, the most likely way we’ll discover exoplanet life is by looking at their atmospheres.

April 2, 2021April 2, 2021 by Matt Williams

If Astronomers see Isoprene in the Atmosphere of an Alien World, There’s a Good Chance There’s Life There

Artists’s impression of the rocky super-Earth HD 85512 b. Credit: ESO/M. Kornmesser

It is no exaggeration to say that the study of extrasolar planets has exploded in recent decades. To date, 4,375 exoplanets have been confirmed in 3,247 systems, with another 5,856 candidates awaiting confirmation. In recent years, exoplanet studies have started to transition from the process of discovery to one of characterization. This process is expected to accelerate once next-generation telescopes become operational.

As a result, astrobiologists are working to create comprehensive lists of potential “biosignatures,” which refers to chemical compounds and processes that are associated with life (oxygen, carbon dioxide, water, etc.) But according to new research by a team from the Massachusetts Institute of Technology (MIT), another potential biosignature we should be on the lookout for is a hydrocarbon called isoprene (C₅H₈).

March 21, 2021March 21, 2021 by Andy Tomaswick

Oh, the Irony. There are Likely Water Worlds Everywhere, but They’re Covered in ice and Impossible to Investigate

Liquid water was originally thought to be relatively rare in the solar system. But one of the most important discoveries of the last several decades of planetary science is that liquid water is extremely common, even outside of the orbit of a star that would allow for it on the surface of a planet or moon. It just happens to be covered by a sheet of ice. Scientists at the Southwest Research Institute (SwRI) have now theorized about what the abundance of liquid water means for life throughout the galaxy, and whether it might be more common than originally thought.

March 12, 2021March 12, 2021 by Ralph Crewe

A Planet Lost Its Atmosphere, So Its Volcanoes Made It a New One

Credit: NASA, ESA, and R. Hurt (IPAC/Caltech)

A red-dwarf star called Gliese 1132 or GJ 1132 for short (astronomers and their fun nicknames!) smolders on some 41 light-years from the sun in the southern constellation Vela, just a few degrees away from the southern cross. In 2015, astronomers using the MEarth South telescope array at Cerro Tololo Inter-American Observatory (CTIO) in Chile found an Earth-sized planet orbiting extremely close to the little red star. Known as GJ 1132b, the planet orbits in a blistering 1.6 days. Its original hydrogen and helium atmosphere is thought to have long since been blown away by the powerful stellar winds experienced by the planet due to its extreme proximity to its parent. New observations from the Hubble Space Telescope revealed a surprise from the speedy exoplanet; it seems to have re-formed an atmosphere!

March 11, 2021March 11, 2021 by Andy Tomaswick

Vega Might Have a Planet

Vega is one of the brightest and best known stars in the night (or even twilight) sky. Located in the constellation Lyra, it is only 25 light years from Earth, and about twice our Sun’s mass. And now, astronomers might have found one of the hottest known planets orbiting it extraordinarily quickly.

March 10, 2021March 8, 2021 by Paul M. Sutter

This Exoplanetary System Breaks all the Rules

A cartoon of the K2-290 system, where two planets orbit backwards relative to the spin of their parent star. Image credit: Christoffer Grønne

It’s just like a normal solar system…except completely backwards.

February 18, 2021February 18, 2021 by Evan Gough

We Could Find Extraterrestrial Civilizations by Their Air Pollution

Exoplanet Kepler 62f would need an atmosphere rich in carbon dioxide for water to be in liquid form. Artist's Illustration: NASA Ames/JPL-Caltech/T. Pyle

Upcoming telescopes will give us more power to search for biosignatures on all the exoplanets we’ve found. Much of the biosignature conversation is centred on biogenic chemistry, such as atmospheric gases produced by simple, single-celled creatures. But what if we want to search for technological civilizations that might be out there? Could we find them by searching for their air pollution?

If a distant civilization was giving our planet a cursory glance in its own survey of alien worlds and technosignatures, they couldn’t help but notice our air pollution.

Could we turn the tables on them?

February 11, 2021February 11, 2021 by Evan Gough

Possible Super-Earth in the Habitable Zone at Alpha Centauri

Kepler-22b, seen in this artist's rendering, is a planet a bit larger than Earth that orbits in the habitable zone of its star. Some researchers think there might be "superhabitable" worlds that may not resemble Earth. c. NASA

Astronomers using a new technique may have not only found a super-Earth at a neighbouring star, but they may also have directly imaged it. And it could be nice and cozy in the habitable zone around Alpha Centauri.