We know of many planets orbiting outside the solar system that, according to scientists, could potentially hold the ingredients responsible for life. However, they are often so far away we can’t glean much information from them. One way to bypass the problem is to simulate the atmospheric conditions of these cosmic bodies, known as exoplanets, in a lab. Now Researchers at Johns Hopkins University (JHU) have drastically advanced these simulations by conducting the first-ever lab experiments on haze formation in a simulated exoplanet atmosphere.
The study, published in the journal Nature Astronomy, will help scientists create much better and more comprehensive exoplanet simulations. “One of the reasons why we’re starting to do this work is to understand if having a haze layer on these planets would make them more or less habitable,” said Sarah Hörst, lead author and assistant professor of Earth and planetary sciences at JHU, in a press release.
While scientists can use telescopes to explore what gases make up the atmospheres of exoplanets, these telescopes don’t work as well with planets that have hazy atmospheres. This haze, which is made up of gas with suspended solid particles, interacts with light preventing researchers from measuring and understanding the planet’s gas composition.
It might seem surprising that these researchers are able to reproduce environments that we can’t fully see, let alone understand. But the research team was able to model the atmospheric conditions of super-Earths or mini-Neptunes (the predominant type of exoplanet we have found thus far) by working with a combination of gases they already knew well. In particular, they mapped different levels of three main gases (carbon dioxide, hydrogen, gaseous water), four other gases (helium, carbon monoxide, methane, nitrogen), and three sets of temperatures. Using this method they “created” nine virtual planets.
This research could give scientists the tools to better predict if an unknown exoplanet is likely to be hazy. “Having a haze layer can change the temperature structure of an atmosphere,” said Hörst. Some scientists think that early-Earth may have been protected by such a haze, and so understanding exactly how a haze layer affects the surface of an exoplanet could clue researchers into potential locations for past or future life.
Additionally, with the upcoming launch of the James Webb Space Telescope, it is possible that better understanding this haze will give scientists the information necessary to find ways to peer through it. Haze has stood between scientists and exoplanet research for many years, but now we might not only be able to see through the haze, learning about its nature could help us to better understand life’s origins.
Enceladus, one of Saturn’s moons, is a leading candidate in the search for extraterrestrial life in our solar system. One new study improves the moon’s likelihood of holding life. Scientists have found that, under Enceladus-like conditions, certain microbes known as methanogenic archaea can grow and produce methane from carbon dioxide and hydrogen gases.
These researchers suggest that the geochemical reactions in Enceladus’ rocky core could produce enough methane to support such microbes — pointing a hypothetical ecosystem for such life.
To reach these conclusions, the research team, led by Simon Rittmann of the University of Vienna, used unique gas compositions and pressures in the lab to mimic the environment that is predicted to exist on Enceladus. They then cultured three different microscopic organism species in this environment. They found that, among the species cultivated, Methanothermococcus okinawensis was able to produce methane and thrive despite the presence of growth-inhibiting compounds. The resulting study was published in the journal Nature.
Looking to Enceladus
Enceladus’ icy crust hides a global ocean, and its southern pole is rife with hydrothermal activity. This Saturnian satellite also cultivates heat from friction with Saturn, and is home to a variety of compounds that are also common on Earth — molecular hydrogen, methane, carbon dioxide.
Future missions to observe the moon could use research on its potential inhabitants to guide and inform their goals, allowing them to gather the most pertinent data. Many entities, including NASA, are considering the possibility of reaching Enceladus to complete direct observations. Geoffrey Marcy, a retired professor of astronomy at the University of California, Berkeley, even told Astrowatch that such missions wouldn’t even need to land to collect the information they need; a spacecraft flying through the moon’s many vapor plumes might be able to collect enough samples to make the link.
As we learn more about the icy water worlds in our own backyard, it seems more likely that Enceladus and its fellow ice moons may play host to life as we do not yet know it. We might not know for sure until a mission departs, but until then, research like this will give such missions the tools they will need to succeed.
If science fiction’s to be believed, humans are going to absolutely freak out when we first encounter extraterrestrials — we’re talking pandemonium, nothing short of out-and-out hysteria. From Independence Day to Alien, your average human in a movie doesn’t take well to meeting our newly-discovered alien neighbors, who, to be fair, are usually threatening the widespread elimination of humans in some way.
But if you talk to the average person, you might get a different picture of what a reaction to first contact might look like. Most people aren’t so alarmed. In fact, they’re pretty optimistic about what meeting aliens might mean. Most of us are like the kids in E.T., rather than the terrified adults: A reaction that’s less reflexive hostility, more peaceful curiosity.
A new study suggests that, in the event of an extraterrestrial encounter, the rioting and looting would be kept to a minimum — humans would actually react pretty positively to the news.
Michael Varnum, assistant professor of psychology at Arizona State University, took several different approaches in his study, which he presented during a press briefing at the annual meeting of the American Association for the Advancement of Science (AAAS) in Austin, Texas.
For the first part, he and his team used a computer program to analyze the language used in news articles about discoveries that indicated the possibility of alien life. The program focused on the emotional timbre of the articles and found that the media coverage was generally positive. The researchers also made a (hypothetical) announcement that humans had detected extraterrestrial microbial life, and asked more than 500 people to offer their written responses. Again, the language the authors used was largely positive.
As for something that feels a bit more real? In the final part of the study, the researchers asked 500 people to respond to one of two articles in the New York Times about real scientific discoveries: evidence of microbial life on a Martian meteorite and the creation of synthetic life in a lab. Interestingly, participants reacted more positively to the possibility of alien life than the human capacity to create life.
“[T]aken together, this suggests if we find out we’re not alone, we’ll take the news rather well,” said Varnum in a press release.
Varnum’s studies, it should be noted, only took American perspectives into account. First contact would affect the entire human population (and probably some other types of organisms, too), and different cultures might respond to the news very differently.
Plus, it’s easy to be optimistic about something that you know hasn’t happened. Many of us are simply rosy about going to the gym, but hate it once we’re actually there (or, conversely, we hate the idea of going to the gym, but love it once we’re actually exercising). After all, we are humans, and we do tend to do a great job of tricking ourselves into looking forward to things.
If scientists have their way, the question of whether extraterrestrials exist won’t be hypothetical for long— increasingly sophisticated technology will help us detect aliens, if in fact they’re out there. Playing out possible scenarios and getting a sense for how humanity would react to such a discovery could help governments come up with better-informed policies for how to handle first contact, when and if it arises.
Ultimately, we can at least hope that humans would have an upbeat reaction to the discovery of alien life. We can test the waters, make policies, or play out different scenarios in the fictional space all we like.
But the best way to figure out how humans will react to extraterrestrials? Find the aliens. Then we’ll really get to see if humans are as upbeat as researchers predict.
Thanks to the cryptocurrency craze, we might miss out on a call from E.T. Astronomers are reporting that they can’t as easily access the graphics processing units (GPUs) needed to run their powerful telescopes and radio arrays, as they’re being bought up by those looking to mine cryptocurrency.
Daniel Werthimer, chief scientist for the SETI (Search for Extraterrestrial Intelligence) project at the University of California-Berkeley, told the BBC that he’s found GPUs in short supply only over the past few months. Aaron Parsons, another Berkeley astronomer who works on the Hydrogen Epoch of Reionisation Array (Hera) radio telescope, had a similar story: he told the BBC that the price of GPUs his team needed had doubled.
Though designed specifically to render visual tasks, GPUs have been recruited for cryptocurrency mining thanks to their speed and efficiency at performing the repetitive computations needed. But they’re also essential for scientists that need to process large quantities of data, like those scanning radio waves from huge swaths of the universe in hopes of catching an extraterrestrial message.
“At SETI we want to look at as many frequency channels as we possibly can because we don’t know what frequency ET will be broadcasting on,” Werthimer told the BBC. “And we want to look for lots of different signal types – is it AM or FM, what communication are they using?” As a result, SETI has as many as 100 GPUs at some telescopes.
Radio astronomy isn’t the only victim of the cryptocurrency craze; a 2017 report highlighted the high carbon emissions produced by crypto mining, which requires large quantities of energy. Yet that cost could be remedied if the electricity needed were generated from renewable resources, rather than fossil fuels.
Parsons expressed concern that radio astronomy work, meanwhile, could be halted entirely if the GPU shortage continues. In that time, we could potentially miss a call from our galactic neighbors — and Earth doesn’t currently have an answering machine.
Disclosure: Several members of the Futurism team, including the editors of this piece, are personal investors in a number of cryptocurrency markets. Their personal investment perspectives have no impact on editorial content.
For the first time in history, astrophysicists have discovered planets beyond the Milky Way galaxy. These extragalactic planets have masses between those of the Moon and Jupiter, and they fully confirm suspicions that our galaxy isn’t the only one to house planets.
“We are very excited about this discovery. This is the first time anyone has discovered planets outside our galaxy,” said Xinyu Dai, professor in the Homer L. Dodge Department of Physics and Astronomy, OU College of Arts and Sciences, in a university press release.
“These small planets are the best candidate for the signature we observed in this study using the microlensing technique,” said Dai. “We analyzed the high frequency of the signature by modeling the data to determine the mass.”
Microlensing is an astronomical effect by which an object’s gravitational field bends the light from a star or quasar as it passes by it. When the object is between the Earth and that light source, this effect creates images that we can detect on Earth.
Until now, all of the objects discovered using microlensing have been within the limits of the Milky Way galaxy. The team used data from the National Aeronautics and Space Administration’s Chandra X-ray Observatory to expand this to include these extragalactic planets.
Analyzing any of the planets discovered within this study would be a concrete impossibility using existing telescope technologies. As OU postdoctoral researcher Eduardo Guerras noted in the OU press release, this study reveals the potential for microlensing to expand our understanding of the universe beyond the Milky Way.
“This is an example of how powerful the techniques of analysis of extragalactic microlensing can be,” said Guerras.
“This galaxy is located 3.8 billion light-years away, and there is not the slightest chance of observing these planets directly, not even with the best telescope one can imagine in a science fiction scenario. However, we are able to study them, unveil their presence, and even have an idea of their masses.”
This solid confirmation of planets beyond our galaxy is an incredible feat, and it opens up a world of possibilities in research. The better we understand the universe, the better we understand how natural processes operate here on Earth, how our solar system formed, and why intelligent life emerged on our planet.
Because of this innovative study, scientists now have the option to look outside our galaxy for answers to these fundamental questions and more. As Guerras concisely summarized in the press release, “This is very cool science.”
Despite an observable universe sprinkled with several trillion galaxies, each stuffed with a trillion planets, we see no evidence of anyone. No signals, no megastructures, no interstellar rockets. While astronomers routinely uncover puzzling objects in the sky, these always turn out to be manifestations of natural phenomena.
Without mincing words, we can state that the cosmos has offered us no hint of the presence of beings as clever as, or cleverer than, Homo sapiens.
It’s tempting to jump from this observational fact to a disappointing conclusion: There’s no one out there. That’s not to say that the universe is sterile. Most astrobiologists seem comfortable with the premise that life might be widespread. But their optimism doesn’t always extend to complex, intelligent life.
It’s possible that we inhabit a universe whose occupants are mostly pond scum. After decades of seeing semi-humanoid aliens strut across the silver screen, it would be more than a little disappointing to think that the actual cosmic bestiary largely consists of plants and animals that are microscopic, or at best, no smarter than cane toads.
That situation would make humans very special, a circumstance that seems at odds with the enormous amount of real estate available for life, as well as the billions of years since the Big Bang during which intelligence could arise.
So, could there be a plausible explanation for why the universe seems so short on keen-witted company?
Filtering Out Intelligent Life
Economist Robin Hanson has suggested that life inevitably encounters a barrier on its evolutionary path to thinking critters – a Great Filter that keeps down the average IQ of the universe.
What could this barrier be? Perhaps life itself is rare because it’s difficult to cook up in the first place. Maybe the transition from single-celled to multi-celled organisms is a bridge too far for most ecosystems. Possibly the emergence of intelligence is a fluke, like winning the Powerball, or perhaps all thinking beings inevitably engineer their own destruction shortly after developing technology.
The idea that there are insurmountable hurdles in the path to intelligence leads to an interesting corollary. Consider the possibility that we’ll someday find microbes under the dry surface of Mars, or beneath the frozen ice of a moon like Enceladus or Europa. That would tell us that one hurdle – the origin of life – can be removed from the list. After all, if biology began on both Earth and another nearby world, then it’s a safe bet that it’s commonplace. No strong filter there.
If we were to discover more sophisticated life somewhere, perhaps equivalent to trilobites or dinosaurs, that would also eliminate some of the postulated filters. Indeed, Nick Bostrom, at Oxford University, has said that it would be horrifyingly bad news to find such complex organisms on another world. Doing so would tell us that the Great Filter is in our future, not our past, and we are doomed. Homo sapiens will come up against a wall that keeps us from extending our dominion beyond Earth. Our species, as lovely and promising as it is, would would have a destiny that is short and dismal.
The appeal of the Great Filter idea is that it takes a fairly limited observation – we don’t see any evidence of aliens in the night sky – and draws an astounding (if dystopian) conclusion about humanity’s destiny.
Could the Great Filter Theory be Full of Holes?
One could argue whether the various hurdles that have been suggested are really all that daunting. For example, the claim that the evolutionary step from insensate creatures to thinking beings could be incredibly unlikely.
A premise of the Rare Earth hypothesis, put forward in a book by Peter Ward and Don Brownlee, published nearly two decades ago, is that the physical conditions of our planet are both finely tuned for our existence and seldom encountered elsewhere. Yes, smart creatures arose on Earth, but that’s because our planet is really special. However, the recent detection of thousands of planets around other stars suggests that terrestrial worlds are hardly in short supply. If there is a Great Filter, it’s not likely to be lack of suitable habitats.
Other suggested barriers to intelligence are less easily dismissed because they depend as much on sociology as on astronomy. Many people seem almost proud to bray that humanity is going to Hades in a handbasket. If nuclear war doesn’t do us in, climate change will. But given that we have at least a chance of being smart about these threats and avoiding total self-destruction, it seems pretty clear that some reasonable fraction of alien societies will also be able to keep themselves alive and kicking for the long term.
Indeed, it’s my opinion that the Great Filter idea falters not on the merits or otherwise of the proposed filters, but on the initial premise: Namely that, because we don’t see any evidence for other intelligence, we require some general mechanism to keep the cosmos short on sentience. Sure, it’s amusing to enumerate some of the difficulties in going from murky chemical soup to space-faring beings, but it seems far more likely that the problem here is a too-hasty conclusion about the prevalence of cosmic confreres.
The efforts to find radio and light signals from other worlds, known as SETI (the Search for Extraterrestrial Intelligence), has so far failed to uncover any hailing signals from aliens. But these experiments are both underfunded and still in their early days. Even if the universe is chock-a-block with transmitting societies, SETI could easily miss them, simply because of inadequate instrument sensitivity or the fact that only a small number of star systems have yet to be searched.
A common, and regrettable, error is committed when people note that the SETI scientists have been toiling for more than 50 years without a discovery, as if that suggests that intelligence is rare. It doesn’t. Throughout most of that period, observations were restricted by the lack of telescope time or by receivers that could only examine small slices of the radio dial.
In addition, it’s worth remarking that humanity is in the process of developing artificial intelligence, a technological trajectory that other sophisticated societies could very well follow. Unlike biological intelligence, AI can self-improve at tremendous speed. Also, there aren’t obvious limitations to the spread of machines throughout the cosmos. The implication of this observation is that the majority of the intelligence in the universe is likely to be synthetic. And machine intelligence might be small, localized, and cryptic.
The absence of evidence would hardly qualify as evidence of absence. The Great Filter theory, in other words, could be no more than an appealing solution looking for a problem.
With its vast oceans and methane-filled rivers and lakes, Titan is a prime candidate for the search for extraterrestrial life. While our knowledge of Saturn’s largest moon grew tremendously thanks to the now-defunct Cassini mission, the question of whether Titan is home to primitive lifeforms remains a mystery. Now, NASA’s recent selection of Titan as a possibility for further exploration under its next New Frontiers mission indicates they might want more answers. Selected from a field of 12 possibilities, NASA chose a quad-copter known as “Dragonfly” as one of two finalists for its next nearly billion-dollar mission. The “Dragonfly” drone, like its namesake, would flit between different parts of Titan’s surface to study the moon’s landscape and its habitability.
The other contender is a mission to the comet 67P/Churyumov-Gerasimenko, where a lander would snag a piece of the comet’s nucleus and return it to Earth for further study.
The plutonium-powered drone would alternate between taking measurements on the moon’s surface and flying from one site to another, traveling tens to hundreds of kilometers with each flight.
Elizabeth Turtle, principal investigator for Dragonfly from Johns Hopkins University Applied Physics Laboratory, told the HUB, “Titan is a fascinating ocean world. It’s the only moon in the solar system with a dense atmosphere, weather, clouds, rain, and liquid lakes and seas—and those liquids are ethane and methane. There’s so much amazing science and discovery to be done on Titan.” During a NASA teleconference on December 20, 2017, Turtle said the Dragonfly was expected to land on Titan in 2034.
Many scientists have compared the conditions on the surface of Titan to the conditions that may have existed on early Earth. In fact, NASA even stated that, “In many respects, Saturn’s largest moon, Titan, is one of the most Earth-like worlds we have found to date.” So even if life is never discovered on Titan itself, it could be an ideal place to explore how life came about on Earth.