Hunting for life on other worlds isn’t easy.
Victor Habbick Visions/Science Photo Library via Getty Images
It’s hard to look for something you’ve never seen before – and that might not even exist. But you have to start somewhere.
An artist’s illustration of hydrogen disappearing from Venus.
Aurore Simonnet/ Laboratory for Atmospheric and Space Physics/ University of Colorado Boulder
Studying Venus’ water loss can help scientists better understand how planets go from potentially habitable to incapable of supporting life.
The equipment planned to help bring samples back from Mars.
NASA/JPL
It’s not easy to collect rocks on a budget when the rocks are 140 million miles away.
NASA/JPL-Caltech
The Perseverance rover has arrived at what’s thought to be an ancient shoreline on Mars.
Scientists could one day find traces of life on Enceladus, an ocean-covered moon orbiting Saturn.
NASA/JPL-Caltech
Saturn’s moon Enceladus has geysers shooting tiny grains of ice into space. These grains could hold traces of life − but researchers need the right tools to tell.
NASA
An instrument on the Europa Clipper mission might be able to detect biological cells from space.
The surface of Mars is cold, dry and rocky.
NASA/JPL-Caltech/ASU
Determining whether or not life exists on another planet is an extraordinarily complicated – and expensive – scientific endeavor.
Scientists have been studying the Clarkia site for nearly five decades.
Robert Patalano
While NASA rovers on the surface of Mars look for hints of life, researchers back on Earth are studying ‘echoes of life’ from ancient basins – hoping that the two sites might be similar.
Tim Johnson / Unsplash
‘Assembly theory’ aims to explain evolution without biology. Is it a dazzling breakthrough or an attempt to answer questions nobody asked?
Meteorites can get pricey, but they’re not the most expensive material.
AP Photo/Thibault Camus
Some space rocks you can get for free – if you know how to identify them. Rarer materials cost more, and the asteroid sample NASA just brought back has a high price tag.
The exoplanet K2-18b might host a water ocean.
Credits: Illustration: NASA, CSA, ESA, J. Olmsted (STScI), Science: N. Madhusudhan (Cambridge University)
The results are intriguing, but analysing the atmospheres of exoplanets is no easy task.
In 2021, scientists thought they had discovered phosphine in the clouds of Venus.
NASA
Alien hunters should learn from the Intergovernmental Panel on Climate Change (IPCC).
Israel Pina / Unsplash
Some physicists think we live in a multiverse, surrounded by universes not quite like our own. What does that mean for life?
Scientists think Mars rovers may have some blind spots when it comes to finding signs of life.
Shutterstock
Our Mars rovers might not be sensitive enough to detect signs of life. But lessons from Antarctica might make future missions more successful.
TRAPPIST-1e is a rocky exoplanet in the habitable zone of a star 40 light-years from Earth and may have water and clouds, as depicted in this artist’s impression.
NASA/JPL-Caltech/Wikimedia Commons
Life on Earth has dramatically changed the chemistry of the planet. Astronomers will measure light that bounces off distant planets to look for similar clues that they host life.
Artist’s impression of ‘Oumuamua.
ESO/M. Kornmesser
There’s a good reason why so many scientists disagree with claims that Earth has been visited by aliens.
Perseverance in action.
NASA/JPL-Caltech
Methane gas in the atmosphere is a tantalising hint suggesting that life could exists on Mars.
This artist’s rendering shows OSIRIS-REx spacecraft descending toward asteroid Bennu to collect a sample of the asteroid’s surface.
NASA/Goddard/University of Arizona
OSIRIS-REx will touch down on asteroid Bennu, collect a sample of the dust and begin its journey back to Earth, where scientists will study it, hoping to learn secrets of the solar system’s origin.
There seems to be a network of underground bodies of liquid water at Mars’ south pole.
NASA/JPL/Malin Space Science Systems
New findings boost chances of finding life on Mars, but there are better candidates in the solar system.
Purple microbial mats offer clues to how ancient life functioned.
Pieter Visscher
How ancient microbes survived in a world without oxygen has been a mystery. Scientists discovered a living microbial mat that uses arsenic instead of oxygen for photosynthesis and respiration.