alien life Archives

January 11, 2025January 11, 2025 by Mark Thompson

Could We Detect Advanced Civilisations by their Industrial Pollution? Probably Not.

The MAIA satellite mission, a partnership between NASA and Italy's Agenzia Spaziale Italiana (ASI), will investigate the effects of particulate matter air pollution on human health. Suicup/Wikimedia Commons, CC BY-SA 3.0

The hunt for aliens goes hand in hand with the hunt for habitable planets. Astronomers are on the hunt for exoplanets with atmospheric chemicals that could be a sign of an advanced civilisation. These chemicals, known as technosignatures are found on Earth and are the result of burning fossil fuels. A team of researchers have been exploring Polycyclic Aromatic Hydrocarbons and whether they could detect them.

January 2, 2025January 2, 2025 by Mark Thompson

Could There Be Bacteria Living on Mars Today?

Methanogens. Credit: Maryland Astrobiology Consortium, NASA, and STScI.

Mars is often considered to be the planet most similar to the Earth. Earth however, is capable of supporting life, Mars on the other hand could not. There was once a time when it was warmer and wetter and could support life. Exploring life on Earth shows us that bacteria known as extremophiles can live in the most harsh conditions on Earth, it may just be possible that there are places on Mars that could also support these hardy forms of life. A new paper explores that possibility by studying the most extreme Earth-based bacteria that could survive under ground on Mars.

August 29, 2024August 29, 2024 by Mark Thompson

Giant Low-Frequency Scan Searches for Aliens in 2,800 Galaxies

One of the tiles making up the 32T, a prototype instrument for the Murchison Widefield Array. Natasha Hurley-Walker

The search for extraterrestrial intelligence (SETI) has fascinated us for decades. Now a team of researchers have used the Murchison Widefield Array in Australia to scan great swathes of sky for alien signals. Unusually for a SETI project, this one focussed attention on 2,800 galaxies instead of stars within our own. They have been on the lookout for advanced civilisations that are broadcasting their existence using the power of an entire star. Alas they weren’t successful but its an exciting new way to search for alien intelligence.

May 24, 2024May 25, 2024 by Mark Thompson

Toxic Perchlorate on Mars Could Make Life More Interesting

Credit: Joseph Heili, Tanner Hoog, and Aaron Engelhart

The search for life in the Universe has fascinated humans for centuries. Mars has of course been high on the list of potential habitats for alien existence but since the numerous spacecraft images that have come back showing a barren landscape, it seems Mars may not be so habitable after all. That is, until recently. The Martian regolith, the top layer of dust upon the surface has been found to be full of perchlorate salts. These chemicals are poisonous to most life on Earth but a new study suggests that some extremophile protein enzymes and RNA may just be able to survive!

April 8, 2024April 8, 2024 by Mark Thompson

Testing a Probe that Could Drill into an Ice World

SLUSH prototype probe set up over an ice tower. Bottom left: Top view of 1.4 m borehole created by the SLUSH prototype probe. Middle: Dolphin Probe being tested inside an ice tower. Right: Salmon Probe being tested on top of Devon Island Ice Cap.

I remember reading about an audacious mission to endeavour to drill through the surface ice of Europa, drop in a submersible and explore the depths below. Now that concept may be taking a step closer to reality with researchers working on technology to do just that. Worlds like Europa are high on the list for exploration due to their potential to harbour life. If technology like the SLUSH probe (Search for Life Using Submersible Head) work then we are well on the way to realising that dream.

February 13, 2024February 13, 2024 by Mark Thompson

The SETI Ellipse Tells Us Where to Search for Extraterrestrial Civilizations

The SETI Ellipsoid (Image credit: Zayna Sheikh)

Of all the questions that remain unanswered, the question of life in the Universe is surely the one that captures our attention the most. In a Universe whose observable edge is 46 billion light years away, is it even conceivable that we are alone, the sole planet among the millions and perhaps billions that are out there, where life has evolved, an oasis of life in the cosmic ocean. In the search for alien civilisations, researchers have proposed that it may be possible to use bright galactic events like supernovae to act as a focal point for civilisations to announce their presence!

October 30, 2023October 30, 2023 by Brian Koberlein

Want to Find Life? Compare a Planet to its Neighbors

Earth compared to the exoplanet Kepler-186f. Credit: NASA's Goddard Space Flight Center

With thousands of known exoplanets and tens of thousands likely to be discovered in the coming decades, it could be only a matter of time before we discover a planet with life. The trick is proving it. So far the focus has been on observing the atmospheric composition of exoplanets, looking for molecular biosignatures that would indicate the presence of life. But this can be difficult since many of the molecules produced by life on Earth could also be produced by geologic processes. A new study argues that a better approach would be to compare the atmospheric composition of a potentially habitable world with those of other planets in the star system.

September 11, 2023September 11, 2023 by Brian Koberlein

JWST Might Have Imaged a Hycean World for the First Time, With a Hydrogen-Rich Atmosphere and a Deep Planet-Wide Water Ocean

Artist depiction of the mini-Neptune K2-18 b. Credit: NASA, CSA, ESA, J. Olmstead (STScI), N. Madhusudhan (Cambridge University)

Despite its great oceans, Earth is not really an ocean world. It has less water than icy moons such as Europa and Enceladus, a relatively thin nitrogen-rich atmosphere, and vast continents that rise above sea level. A true ocean world would have no continents, a warm sea hundreds of kilometers deep, and a thick hydrogen and water-rich atmosphere. They are known as hydrogen-ocean planets or hycean worlds. While we’ve long thought they exist, the James Webb Space Telescope may now have found one.

November 4, 2021 by Andy Tomaswick

NASA is Getting Serious About the Search for Life in the Universe

Frameworks are a valuable tool in science. They give context to sometimes abstract concepts such as “how powerful can an alien civilization be” (Kardashev scale) or “how developed is this technology?” (Technology Readiness Levels). Now, NASA has developed a new scale to help give context to what some consider one of the agency’s most critical missions – the search for extraterrestrial life.

September 20, 2020September 21, 2020 by Matthew Cimone

How Much Life Would Be Required to Create the Phosphine Signal on Venus?

How can astronomers tell exo-Earths and exo-Venuses apart? Polarimetry might be the key. Image Credits: NASA

A Biosignature

Last week, an incredible announcement was made about the search for extraterrestrial life: Phosphine gas detected in the clouds of Venus – a potential indicator of life or “biosignature.” Now some gases might be a false positive for biosignatures because they can be created by other chemical processes on a planet like photochemical processes in the atmosphere or geological processes beneath the surface that create a given gas. For example, methane can also be a biosignature, and we’ve been hunting it down on Mars, but we know that methane can also be created geologically. Finding phosphine in Venusian clouds is truly remarkable because we don’t presently know of any way to create phosphine abiotically or without life being a part of the equation. Question is – how much life??