A large anthology of stories and accompanying essays about unusual non-human life, which may be sentient, and how we might meet them. Stories that I found interesting were by Eric Choi, Geoffrey A. Landis, Rich Larson, Lisa Jenny Krieg, Tobias S. Buckell, Valentin D. Ivanov, Gregory Benford, Peter Watts, Simone Heller and Mary Robinette Kowal.

• "Hemlock on Mars", short story by Eric Choi: a mission to Mars is in jeopardy when it is discovered to be harbouring Earth organisms and may contaminate its landing zone. Mission controllers work to resolve the issue: at the same time, one of the leaders have to struggle with a personal crisis that, in the end, would influence the outcome of the mission.

• "Planetary Protection", essay by Giovanni Poggiali, talks about the history of the Planetary Protection Protocol and how it applies to space probes not contaminating their mission targets.

• "The Dog Star Killer", short story by Renan Bernardo: a cloud of molecules in interstellar space is detected approaching the solar system and may cause more cosmic radiation to reach the earth. To learn more about it, a mission was launched to the cloud, but was lost. Now, years later, a beacon signal is from the lost mission is detected, and a rescue mission is launched, piloted by a daughter of one of the original explorers. As told in a series of flash-back episodes, she has many reasons, historical and personal, for finding out what happened to her mother on the mission.

• "That Cold Black Cloud", essay by Stefano Sandrelli, talks about the history of what we know about molecular clouds in interstellar space, known as Bok globules, and how they may affect the heliosphere produced by the sun if such a cloud were to intersect with the heliosphere.

• "Titan of Chaos", short story by G. David Nordley: on Saturn's moon, Titan, a call for help gets an investigator into deep trouble as he attempts to help his ex-wife escape being trapped in the gut of a deep ocean creature on Titan.

• "Flying Instead of Diving", essay by Fabian Klenner, talks about the unusual organic chemistry of the moon, Titan, where the temperature is so cold that water ice is a rock hard solid and biology (if any) might be based on hydrocarbons that are liquid in such conditions.

• "Cloudskimmer", short story by Geoffrey A. Landis: a member of a team exploring the atmosphere of Venus takes a ride on a drone to see what the atmosphere of Venus is like, and discovers an something interesting.

• "Earth's Sister Planet", essay by Dennis Honing, discusses the current state of Venus and speculations about where it might have liquid water in an earlier age before it became the hot and dessicated planet we know it today.

• "The Lament of Kivu Lacus", short story by B. Zelkovich: on an outpost on Titan, two people investigate the calls of whale-like creatures that may have a link to a developing crisis in the outpost.

• "Robots in Space Are Great", essay by Ania Losiak, looks at the capabilities of humans and robots in space and concludes that despite the difficulties, humans are currently better at handling the unknown unknowns in space exploration.

• "Heavy Lies", short story by Rich Larson: on an alien world, an all controlling queen prepares to give birth and also to consider whether she is the last remaining intelligent organism on the planet.

• "Major Transitions", essay by Stephen Francis Mann, looks at the transition of life from unicellular to multicellular upwards to intelligent and not-intelligent groupings of animals and how it could apply to aliens.

• "The World of Silver", short story by Tomáš Petrásek: both human and alien struggle to survive on an alien world after a crash. Things are made harder when both of them have different biochemistries (based on water and amonia).

• "Wet Wet Wet", essay by William Bains, looks at the possibilities of alternative chemistries for life based on liquids other than water.

• "Spider Plant", short story by Tessa Fisher: an interstellar expedition to a system where radio signals have been detected finds no alien structures, except for enigmatic planet-wide crystal structures. It would need the crew's expertise to finally detect who was sending the signals.

• "Signs of Life (and How to Find Them)", essay by Tessa Fisher, looks at the details behind the alien life imagined in the story.

• "This Is How We Save Them", short story by Deji Bryce Olukotun: on a terraformed moon, ultrarich families come to hunt animals while contributing to their conservation. But this particular hunt goes off in an unexpected direction.

• "Valuing Life", essay by Erik Persson, looks at the ethics of allowing other worlds to be terraformed to save Earth's biodiversity.

• "The Far Side of the Door", short story by Premee Mohamed: a colony on a planet is suddenly faced with a pandemic after a accidental crash of a ship. Initial surveys have found no life on the planet so it is a rush against time to figure out what is causing it.

• "Space Agriculture", essay by Raymond M. Wheeler, looks at what needs to be done to grow food in space and on Mars.

• "Ranya's Crash", short story by Lisa Jenny Krieg (translated by Simone Heller): on a world whose inhabitants have been modified to survive, one scout is desperate to learn the secrets of an ancient compass that may help the survival of its group. But to do that, she may have to first help a group of giant dragonflies.

• "You Are Not Alone!", essay by Jacques Arnould, looks at what kinds of live may be found in the universe.

• "Spiral", short story by Arula Ratnakar: an explorer finds himself among a form of possible life in a pattern forming region of space.

• "Spiraling Into the Unknown", essay by Tomáš Petrásek, looks at life as we might not know it in the form of plasma.

• "The Last Cathedral of Earth, in Flight", short story by Tobias S. Buckell: a tale of a desperate flight of what is apparently left of humanity, feeling an alien life form born near the reality bending madness that is a black hole.

• "The Latest Black Hole Planet, in Formation", essay by Amedeo Romagnolo, look as the possibility of life near a black hole.

• "The Secret History of the Greatest Discovery", short story Valentin D. Ivanov: the story of an astronomer who, while a student, makes some observations of the brightness of stars and makes a discovery that would need years to confirm.

• "Cooperation Without Communication", essay by Valentin D. Ivanov, looks at how alien civilisations would send out a signal to indicate their presence.

• "Human Beans", short story by Eugen Bacon: a young woman unsure about her place in the world finds people around her vanishing from existence. One day she learns where they vanish to.

• "Microbial Life and Belonging", essay by Tony Milligan, looks at people and life belonging to a world in general, even if it is just microbial life.

• "The Mirrored Symphony", short story by D. A. Xiaolin Spires: a space ship investigating what appears to be a reflected image of a cosmological object discovers an apparently deserted planet with a biological secret.

• "Mirror Images", essay by Dimitra Demertzi, looks at the biology and chemistry of chiral molecules.

• "Lumenfabulator", short story by Liu Yang (translated by Ladon Gao): a son composes a poem while hearing stories of their predecessors from his father. Both son and father have rocky bodies, driven by magna.

• "Crystal Green Persuasion", essay by Nina Kopacz, speculates about living rocks and the forces that make drive them.

• "Cyclic Amplification, Meaning Family", short story by Bogi Takács: communicating with aliens can be difficult, unless the aliens take matters into their own hands to cross the language barrier in their own way.

• "The Science of Xenolinguistics", essay by Sheri Wells-Jensen, looks at the possible difficulties in communicating with aliens.

• "The Diaphanous", short story by Gregory Benford: a self-aware maintenance probe in the outer reaches of the solar system is suddenly attacked by intelligent life in the shape of plasma who don't want it there. It would need skill to discover how stop the attacks and to work with the lifeforms.

• "Life 2.0", essay by Geoffrey A. Landis, looks at the possibility of plasma based life.

• "The Sphinx of Adzhimushkaj", short story by Brian Rappatta: a person picks up a intern while going to study an alien life form. Only, the life form ignores the researchers and he spends most of his time painting. But this time, an event occurs that causes a crisis among the aliens, and his paintings may be a clue as to how to communicate with them.

• "Finding Common Ground", essay by Philippe Nauny: discusses how humans might communicate with aliens with different ways of sensing the environment.

• "Defective", novelette by Peter Watts: wormholes open in the solar system and it was determined that it is a work of an utterly alien race that intends to colonise the sun. Attempts to communicate with them fail and now humanity has little choice but to kill off the wormholes to stop the sun being colonies and potentially consumed. But one person, tasked with trying to communicate with the aliens, think differently.

• "How Did They Know It Was Agni?", essay by Joanna Piotrowska, looks at how spectroscopy can reveal what materials make up other exoplanets and whether they can contain signatures of life.

• "The Dangers We Choose", short story by Malka Older: intelligent life is found on a water world. When it is time to send humans to meet them, it may be up to one person with special sight to lead the team back safely from the meeting.

• "The Habitability of Water Worlds", essay by Floris van der Tak, looks at the possiblity of intelligent life developing on an aquatic world.

• "Third Life", short story by Julie E. Czerneda: a human and an alien bond together over their love of weaving.

• "The Unveiled Possibilities of Biomaterials in Space". essay by Martina Dimoska looks at how some biomaterials, like spider silk, may find a use in space.

• "Forever the Forest", short story by Simone Heller: a sentient forest is started when an object crashes into it which turns out to be a free moving organism. It attempts to contact it in the only ways it can, by scent and movement. Communication of a kind is established and the forest discovers what the organism yeans for and, eventually, decides to help it, even if it means losing contact with it forever.

• "Astra Narrans", essay by Connor Martini, looks at how other organisms experience the world about them and the challenges of trying to communicate with aliens with different senses to experience the world.

• "Still As Bright", short story by Mary Robinette Kowal: set in an alternate Earth where destruction caused by a meteorite forces mankind to go to space early, a former astronomer transports the director of a space based telescope. Along the way, and afterwards, she tries to tell him of her plan to detect planets around other stars (exoplanets).

• "— And the Moon Be Still As Bright", essay by José A. Caballero, looks at how possible it would be in the story's alternate Earth for a space based telescope, manned in space and using technology from the 1970s and 1980s, to be able to detect exoplanets.

• "Devil in the Deep", short story by Lucie Lukačovičová: scientist are helpi to investigate deep mines in the hopes of making it safer. But their efforts to help run into resistance from some miners who feel they are dishonouring the god of the deeps. Thing may change when they discover a form of sentient life in the mines.

• "Some Like It Hot", essay by Natuschka Lee and Lucie Lukačovičová, looks at how microbes might survive in the hot, deep interior of the earth.

• "Deep Blue Neon", short story by Jana Bianchi: written in the from of journal and blog entries, it tells the story of a research on the quest to discover a new species of whale that may well lead to her death when she risks contact to confirm a hunch over what happened when her father had earlier made contact with the whales.

• "Destined for Symbiosis", essay by Jan Toman, takes a low at symbiotic organisms.