In 1960, famed theoretical physicist Freeman Dyson made a radical proposal. In a paper titled “Search for Artificial Stellar Sources of Infrared Radiation” he suggested that advanced extra-terrestrial intelligences (ETIs) could be found by looking for signs of artificial structures so large, they encompassed entire star systems (aka. megastructures). Since then, many scientists have come up with their own ideas for possible megastructures.
Planetary systems can be harsh environments in their early history. The young worlds orbit suns in stellar nurseries, clusters of stars where violent encounters are commonplace. None of this makes it easy for life to get going, but now astronomers at the University of Sheffield find one positive of this tumultuous period. A model developed by undergraduate student Bethany Wootton and Royal Society Dorothy Hodgkin Fellow Dr Richard Parker looks at how the habitable zone – the region around a star where the temperature allows liquid water to exist – changes around pairs of stars, so-called binary systems.
In 1961, famed astronomer Frank Drake created a formula for estimating the number of extra-terrestrial intelligences (ETIs) that could exist within our galaxy. Known as the “Drake Equation“, this formula demonstrated that even by the most conservative estimates, our galaxy was likely to host at least a few advanced civilizations at any given time. About a decade later, NASA officially kicked of its search for extra-terrestrial intelligence (SETI) program.
NASA is targeting technosignatures in its renewed effort to detect alien civilizations. Congress asked NASA to re-boot its search for other civilizations a few months ago. Their first step towards that goal is the NASA Technosignatures Workshop, held in Houston from September 26th to 28th, 2018.
In recent decades, astronomers have discovered many planets that they believe are “Earth-like” in nature, meaning that they appear to be terrestrial (i.e. rocky) and orbit their stars at the right distance to support the existence of liquid water on their surfaces. Unfortunately, recent research has indicated that many of these planets may in fact be “water worlds“, where water makes up a significant proportion of the planet’s mass.
The Cassini orbiter revealed many fascinating things about the Saturn system before its mission ended in September of 2017. In addition to revealing much about Saturn’s rings and the surface and atmosphere of Titan (Saturn’s largest moon), it was also responsible for the discovery of water plumes coming from Enceladus‘ southern polar region. The discovery of these plumes triggered a widespread debate about the possible existence of life in the moon’s interior.
The study of exoplanets -- planets that lie outside our solar system -- could help scientists answer big questions about our place in the universe, and whether life exists beyond Earth. But, these distant worlds are extremely faint and difficult to image directly. A new study uses Earth as a stand-in for an exoplanet, and shows that even with very little light -- as little as one pixel -- it is still possible to measure key characteristics of distant worlds.
When it comes to the search for extra-terrestrial intelligence (SETI) in the Universe, there is the complicated matter of what to be on the lookout for. Beyond the age-old question of whether or not intelligent life exists elsewhere in the Universe (statistically speaking, it is very likely that it does), there’s also the question of whether or not we would be able to recognize it if and when we saw it.
It’s a staple of science fiction, and something many people have fantasized about at one time or another: the idea of sending out spaceships with colonists and transplanting the seed of humanity among the stars. Between discovering new worlds, becoming an interstellar species, and maybe even finding extra-terrestrial civilizations, the dream of spreading beyond the Solar System is one that can’t become reality soon enough!
In 1961, famed astrophysics Frank Drake proposed a formula that came to be known as the Drake Equation. Based a series of factors, this equation sought to estimate the number of extra-terrestrial intelligences (ETIs) that would exist within our galaxy at any given time. Since that time, multiple efforts have been launched to find evidence of alien civilizations, which are collectively known as the search for extra-terrestial intelligence (SETI).
For decades, scientists have been speculating that life could exist in beneath the icy surface of Jupiter’s moon Europa. Thanks to more recent missions (like the Cassini spacecraft), other moons and bodies have been added to this list as well – including Titan, Enceladus, Dione, Triton, Ceres and Pluto. In all cases, it is believed that this life would exist in interior oceans, most likely around hydrorthermal vents located at the core-mantle boundary.
The supertelescopes are coming, enormous ground and space-based observatories that’ll let us directly observe the atmospheres of distant worlds. We know there’s life on Earth, and our atmosphere tells the tale, so can we do the same thing with extrasolar planets? It turns out, coming up with a single biosignature, a chemical in the atmosphere that tells you that yes, absolutely, there’s life on that world, is really tough.
So far, the search for extraterrestrial life has primarily centered on finding two basic clues on alien planets: the presence of water above or below the planet’s surface and significant levels of oxygen in its atmosphere. However, in a new study published in the journal Science Advances, a team of scientists from the University of Washington (UW) detail a novel biosignature search strategy not limited solely to oxygen levels.
Finding past or present microbial life on Mars would without doubt be one of the greatest scientific discoveries of all time. And in just two years’ time, there’s a big opportunity to do so, with two rovers launching there to look for signs of life – Mars2020 by NASA and ExoMars by the European Space Agency and Roscosmos.