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Are there aliens in our own backyard?
Scientists have been probing our solar system for extraterrestrial life.
Humanity has long wondered if life exists elsewhere beyond Earth. With the universe being so mind-numbingly vast, the very idea that our tiny, waterlogged rock should alone harbor life seems so…wasteful.
To sate our curiosity, NASA catalogs exoplanets orbiting Milky Way stars to look for potential cradles of extraterrestrial life, such as Kepler-186f, the first validated Earth-size planet orbiting in its star's habitable zone. And the SETI (Search for Extraterrestrial Intelligence) Institute searches space for clues of alien civilizations by, for example, scanning for the residuals of communication technology like narrow-band radio transmissions.
But is it possible we've set our gaze too far to the horizon? Perhaps the greatest chance we have of finding life beyond Earth isn't orbiting some distant star but can be found in our own solar backyard.
What we look for
When looking for suitable habitats for life, astrobiologists search first and foremost for water. Water is the cornerstone of life on Earth. Life needs solvents to perform biochemical processes, and water's title as the universal solvent means that even the simplest of organisms can use it for their molecular interactions.1
Astrobiologists also look for ways energy may enter a system for metabolic processes. On Earth, this form of energy is typically the Sun; however, recent discoveries have led astrobiologists to search for alternative forms, such as geothermal energy.
Finally, they look for other environmental conditions that make life more or less likely: climate, pressure, temperature, atmospheric makeup, and so on.
We should take this moment to make an important distinction. While our solar system may harbor several havens for life, this life will likely not be the intelligent life that SETI searches for. Any neighborly E.T.s we encounter won't be little grey men or green-skinned vixens so much as a small, microscopic, organisms. Think strange, exotic tardigrades. Well, stranger tardigrades.
Ever since Percival Lowel mapped the “canals" of Mars, our ruddy neighbor has been the go-to planet for science fiction writers imagining extraterrestrial life — from H.G. Wells's colonizing Martians to Ray Bradbury's mystical natives3. The canals proved a trick of the eye, and the Mars Science Laboratory Mission's Curiosity rover has yet to find signs of civilization, but that doesn't mean Mars is out of the extraterrestrial running.
Scientists have discovered dark, narrow streaks on the landscape most likely caused by flowing water. These streaks showed traces of hydrated salt, like what occurs after salt contacts water before it evaporates.
Given Mars' dry, barren landscape and lack of atmosphere, how water got there remains a mystery, but the phenomenon points to the possibility of liquid water not trapped in the planet's polar ice caps, providing a potential habitat for microbial life. Should water flow under the planet's surface, any life could even be shielded from the sun's radiation.
Adding to the intrigue, scientists think that water once covered roughly 20 percent of the surface before Mars's atmospheric gases were stripped away, and the water evaporated into space. Scientists have also discovered meteorites from Mars that contained the remnants of organic material — suggesting the rusted planet once contained the ingredients for life.
Like Mars, Venus likely enjoyed Earth-like conditions back in the day. Computer simulations of its early environment suggest the possibility of primordial oceans, moderate temperatures, and a habitable climate.
As David Grinspoon, of the Planetary Science Institute, told New Scientist: “Both planets probably enjoyed warm liquid water oceans in contact with rock and with organic molecules undergoing chemical evolutions in those oceans. As far as we understand at present, those are the requirements for the origin of life."
If early life did form on Venus, most of it probably vanished 715 million years ago, along with those oceans. Today's Venus sports an infernal landscape of volcanic activity, surface temperatures approaching 750 Kelvin, and a thick, noxious atmosphere of carbon dioxide with clouds of sulfuric acid.4,5
But it is that very toxic atmosphere that may have saved Venusian life. According to a paper in the journal Astrobiology, the atmosphere could provide a safe haven for microbial life. Using spectroscopic observations, researchers found “dark patches" in the atmosphere composed of “concentrated sulfuric acid and other unknown light-absorbing particles."
While it is unknown if these patches are organic or not, they do have the same dimension as some Earth bacteria, and researchers think they could be the Venusian equivalent of algae blooms (like those that appear in our lakes and oceans).
The jets of Enceladus, c/o NAS
Enceladus and Europa
Moving away from Earth's rocky neighbors, astrobiologists are also considering the possibility that life may exist on the moons of Saturn and Jupiter.
When the Cassini-Huygens spacecraft flew past Saturn's sixth moon, Enceladus, it discovered hydrogen gas in an erupting plume of water.6 The eruption suggested hydrothermal activity may be taking place beneath Enceladus' icy surface. If so, the moon would offer two important ingredients for life — water and energy for metabolic processes.7
Europa's surface is similarly covered in ice, with long streaks of “brown gunk." But beneath that surface, scientist estimate that there could be twice as much water as on Earth. If this Jovian moon also produced hydrothermal activity within that ocean, it too could be a harbor for life.8 A study using computer models has even suggested that Europa may have hydrogen and oxygen in amounts comparable to Earth, even if the moon is lacking in volcanic activity.
NASA is planning to launch a Europa flyby mission in the early 2020s, and the agency's SUBSEA project will be studying hydrothermal environments in the Lō`ihi seamount, off the coast of Hawaii's Big Island, to learn how life can thrive on Earth in conditions similar to those possible on Enceladus and Europa.
Our final candidate is Ceres, a dwarf planet and the largest object orbiting in the asteroid belt between Mars and Jupiter. A spherical clump of rock and ice, Ceres would be an unlikely contender for this list until last year, when NASA's Dawn mission detected organic material on its surface.
Originally, it was thought this organic material covered 6–10 percent of the spectral signature, but a recent analysis of the data suggests the amount of could be as high as 40–50 percent. Since carbon-based compounds are necessary for life, it makes for an exciting discovery that could change how we view objects in the asteroid belt.
With that said, this is a recent discovery and much remains unclear. It is possible the organics weren't created on Ceres but planted there by comets, and even if they are native, organic compounds can come about from non-biological processes.
As Ralph Milliken, a professor at Brown University and one of the study's co-authors said in a press release: “Ceres is clearly a fascinating object, and understanding the story and origin of organics in these spots and elsewhere on Ceres will likely require future missions that can analyze or return samples."
The end of life as we know it
So far, our solar search has focused on the conditions for life as we know it. But what about life as we don't know it?
Bacteria recently discovered in Antarctica can survive off just the hydrogen, carbon monoxide, and carbon dioxide they get from the air. These guys make breatharians look gluttonous by comparison and could lead the way to remove water as a prerequisite in our search for extraterrestrial life.
Additionally, Sara Seager, MIT physics professor, considered that alien life may evolve around different chemical combinations than life on Earth and used computer-generated models to devise a list of those possible combinations.
“The theory ended up being, we should maybe consider all potential molecules that would be in gas form," Seager said. “Why not consider all of them? I just combined them in any way possible, like just taking letters in the alphabet and combining them in all ways."
Could life possibly exist in Titan's methane sea? Or could the seeds of life be floating on some yet undiscovered asteroid? The more we learn about life on Earth, the more we learn about the myriad of paths it has taken to thrive, opening avenues for us to find it in our solar system and beyond.
1. Water: The molecule of life. NASA website. Retrieved on July 5, from https://www.nasa.gov/vision/universe/solarsystem/Water:_Molecule_of_Life.html.
2. NASA dives deep into the search for life. NASA website. Retrieved on July 3, from https://www.nasa.gov/feature/ames/nasa-dives-deep-into-the-search-for-life.
3. The “canali" and the first Martians. NASA website. Retrieved on July 5, from https://www.nasa.gov/audience/forstudents/postsecondary/features/F_Canali_and_First_Martians.html.
4. Was Venus the first habitable world of our solar System? Michael J. Way, David H. Grinspoon, et al. Geophysical Research Letters. Retrieved on July 5, from https://arxiv.org/ftp/arxiv/papers/1608/1608.00706.pdf
5. Venus entry. NASA science: Solar system exploration. NASA website. Retrieved on July 4, from https://solarsystem.nasa.gov/planets/venus/in-depth/.
6. Hydrothermal vents on Saturn's moon Enceladus may harbour life. Andrew Masterson. Cosmos. Retrieved on July 5, from https://cosmosmagazine.com/space/hydrothermal-vents-on-saturn-s-moon-enceladus-may-harbour-life.
7. NASA dives deep into the search for life. NASA website. Retrieved on July 3, from https://www.nasa.gov/feature/ames/nasa-dives-deep-into-the-search-for-life
8. Europa: Our best shot at finding alien life? Paul Rincon. BBC News. Published on March 24, 2017. Retrieved on July 3, from https://www.bbc.com/news/science-environment-38925601
A new study finds that dogs fed fresh human-grade food don't need to eat—or do their business—as much.
- Most dogs eat a diet that's primarily kibble.
- When fed a fresh-food diet, however, they don't need to consume as much.
- Dogs on fresh-food diets have healthier gut biomes.
Four diets were tested<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNTU5ODI1MS9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY1NjY0NjIxMn0._w0k-qFOC86AqmtPHJBK_i-9F5oVyVYsYtUrdvfUxWQ/img.jpg?width=980" id="1b1e4" class="rm-shortcode" data-rm-shortcode-id="87937436a81c700a8ab3b1d763354843" data-rm-shortcode-name="rebelmouse-image" data-width="1440" data-height="960" />
Credit: AntonioDiaz/Adobe Stock<p>The researchers tested refrigerated and fresh human-grade foods against kibble, the food most dogs live on. The <a href="https://frontierpets.com.au/blogs/news/how-kibble-or-dry-dog-food-is-made" target="_blank">ingredients</a> of kibble are mashed into a dough and then extruded, forced through a die of some kind into the desired shape — think a <a href="https://en.wikipedia.org/wiki/Food_extrusion" target="_blank">pasta maker</a>. The resulting pellets are sprayed with additional flavor and color.</p><p>For four weeks, researchers fed 12 beagles one of four diets:</p><ol><li>a extruded diet — Blue Buffalo Chicken and Brown Rice Recipe</li><li>a fresh refrigerated diet — Freshpet Roasted Meals Tender Chicken Recipe</li><li>a fresh diet — JustFoodforDogs Beef & Russet Potato Recipe</li><li>another fresh diet — JustFoodforDogs Chicken & White Rice Recipe.</li></ol><p>The two fresh diets contained minimally processed beef, chicken, broccoli, rice, carrots, and various food chunks in a canine casserole of sorts. </p><p>(One can't help but think how hard it would be to get finicky cats to test new diets. As if.)</p><p>Senior author <a href="https://ansc.illinois.edu/directory/ksswanso" target="_blank" rel="noopener noreferrer">Kelly S. Swanson</a> of U of I's Department of Animal Sciences and the Division of Nutritional Sciences, was a bit surprised at how much better dogs did on people food than even refrigerated dog chow. "Based on past research we've conducted I'm not surprised with the results when feeding human-grade compared to an extruded dry diet," he <a href="https://aces.illinois.edu/news/feed-fido-fresh-human-grade-dog-food-scoop-less-poop" target="_blank">says</a>, adding, "However, I did not expect to see how well the human-grade fresh food performed, even compared to a fresh commercial processed brand."</p>
Tracking the effect of each diet<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNTU5ODI1OC9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY3NjY1NTgyOX0.AdyMb8OEcjCD6iWYnXjToDmcnjfTSn-0-dfG96SIpUA/img.jpg?width=980" id="da892" class="rm-shortcode" data-rm-shortcode-id="880d952420679aeccd1eaf32b5339810" data-rm-shortcode-name="rebelmouse-image" data-width="1440" data-height="960" />
Credit: Patryk Kosmider/Adobe Stock<p>The researchers tracked the dogs' weights and analyzed the microbiota in their fecal matter.</p><p>It turned out that the dogs on kibble had to eat more to maintain their body weight. This resulted in their producing 1.5 to 2.9 times the amount of poop produced by dogs on the fresh diets.</p><p>Says Swanson, "This is consistent with a 2019 National Institute of Health study in humans that found people eating a fresh whole food diet consumed on average 500 less calories per day, and reported being more satisfied, than people eating a more processed diet."</p><p>Maybe even more interesting was the effect of fresh food on the gut biome. Though there remains much we don't yet know about microbiota, it was nonetheless the case that the microbial communities found in fresh-food poo was different.</p><p>"Because a healthy gut means a healthy mutt," says Swanson, "fecal microbial and metabolite profiles are important readouts of diet assessment. As we have shown in <a href="https://academic.oup.com/jas/article/92/9/3781/4702209#110855647" target="_blank">previous studies</a>, the fecal microbial communities of healthy dogs fed fresh diets were different than those fed kibble. These unique microbial profiles were likely due to differences in diet processing, ingredient source, and the concentration and type of dietary fibers, proteins, and fats that are known to influence what is digested by the dog and what reaches the colon for fermentation."</p>
How did kibble take over canine diets?<p>Historically, dogs ate scraps left over by humans. It has only been <a href="https://www.thefarmersdog.com/digest/the-history-of-commercial-pet-food-a-great-american-marketing-story/" target="_blank">since 1870</a>, with the arrival of the luxe Spratt's Meat Fibrine Dog Cakes—made from "the dried unsalted gelatinous parts of Prairie Beef", mmm—that commercial dog food began to take hold. Dog bone-shaped biscuits first appeared in 1907. Ken-L Ration dates from 1922. Kibble was first extruded in 1956. Pet food had become a great way to turn <a href="https://www.dogfoodadvisor.com/choosing-dog-food/animal-by-products/" target="_blank">human-food waste</a> into profit.</p><p>Commercial dog food became the norm for most household canines only after a massive marketing campaign led by a group of dog-food industry lobbyists called the Pet Food Institute in 1964. Over time, for most households, dog food was what dogs ate — what else? Human food? These days more than half of U.S. dogs are <a href="https://www.nytimes.com/2014/08/03/magazine/who-made-that-dog-biscuit.html" target="_blank">overweight or obese</a>, and certainly their diet is a factor.<span></span></p><p>We're not so special among animals after all. If something's healthy for us to eat—we're <em>not</em> looking at you, chocolate—maybe we should remember to share with our canine compatriots. Not from the table, though.</p>
New study suggests the placebo effect can be as powerful as microdosing LSD.
- New research from Imperial College London investigated the psychological effects of microdosing LSD in 191 volunteers.
- While microdosers experienced beneficial mental health effects, the placebo group performed statistically similar to those who took LSD.
- Researchers believe the expectation of a trip could produce some of the same sensations as actually ingesting psychedelics.
Psychedelics: The scientific renaissance of mind-altering drugs<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="92360c805fe66c11de38a75b0967f417"><iframe type="lazy-iframe" data-runner-src="https://www.youtube.com/embed/5T0LmbWROKY?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span><p>For the study published in eLife, the team recruited 191 citizen cosmonauts to microdose either LSD or a placebo over the course of several weeks and note the psychological effects. Volunteers were already microdosing LSD, so there was no true control. Each volunteer was given instructions on creating their own low-dose gel capsules, some containing LSD, others not. Then they mixed the capsules in envelopes so they didn't know if they were taking the real thing or not.</p><p>The trial design was ingenious: each capsule featured a QR code that was scanned after the addition of ingredients but before they were placed in the envelope so that researchers knew what they were ingesting.</p><p>The problem: volunteers sourced their own LSD. Lack of quality control could have had a profound effect on the results. </p><p>The results: LSD microdosers reported feeling more mindful, satisfied with life, and better overall; they also noticed a reduction in feelings of paranoia. </p><p>The catch: the control group felt the same thing, with no statistical difference between the groups. </p><p>Lead author Balázs Szigeti comments on the findings: "This suggests that the improvements may not be due to the pharmacological action of the drug but can instead be explained by the placebo effect." </p>
Credit: Alexander / Adobe Stock<p>Psychedelics are notoriously difficult to control for given the intensity of the experience. Yet there is precedent for the above findings. A <a href="https://link.springer.com/article/10.1007/s00213-020-05464-5" target="_blank">2019 study</a> found that 61 percent of volunteers that took a placebo instead of psilocybin felt some psychedelic effects, with a few volunteers experiencing full-on trips.</p><p style="margin-left: 20px;">"Several stated that they saw the paintings on the walls 'move' or 'reshape' themselves, others felt 'heavy. . . as if gravity [had] a stronger hold', and one had a 'come down' before another 'wave' hit her."</p><p>The Imperial team believes the expectation of a trip might have been enough to produce similar results. Senior author David Erritzoe is excited for future studies on the topic, believing they tapped into a new wave of citizen science that could push forward our knowledge of psychedelic substances.</p><p style="margin-left: 20px;">"Accounting for the placebo effect is important when assessing trends such as the use of cannabidiol oils, fad diets or supplements where social pressure or users' expectations can lead to a strong placebo response. Self-blinding citizen science initiatives could be used as an inexpensive, initial screening tool before launching expensive clinical studies."</p><p>As investments into the psychedelics market explode, with one company <a href="https://www.bloomberg.com/news/articles/2021-03-03/thiel-backed-magic-mushroom-firm-atai-hits-2-billion-valuation" target="_blank">reaching a $2 billion valuation</a>, a recurring irony appears in the long arc of psychedelics and research: the power of our minds might be enough to feel greater life satisfaction and a deeper sense of mindfulness. If that's possible with a placebo, we have to question why the rush to create more pharmacology is necessary. </p><p>This is, mind you, a separate conversation over the role of psychedelics and rituals for group bonding. The function of group cohesion around consciousness-altering substances will continue to play an important role in many communities. </p><p>Of course, we should continue to explore the efficacy of psychedelics on anxiety, depression, suicidal ideation, PTSD, and addiction. <a href="https://bigthink.com/surprising-science/antidepressant-effects" target="_self">Pharmacological dependence</a> is a stain on the psychiatry industry. Whether or not psychedelics can be prescribed for daily use remains to be seen, but we know a moneyed interest is expecting a return on investment—the above company, ATAI Life Sciences, raised $157 million in its Series D round. </p><p>When it comes to wellbeing, some things money just can't buy. How we navigate the tricky terrain of mainstreaming psychedelics remains to be seen. </p><p>--</p><p><em>Stay in touch with Derek on <a href="http://www.twitter.com/derekberes" target="_blank">Twitter</a> and <a href="https://www.facebook.com/DerekBeresdotcom" target="_blank" rel="noopener noreferrer">Facebook</a>. His most recent book is</em> "<em><a href="https://www.amazon.com/gp/product/B08KRVMP2M?pf_rd_r=MDJW43337675SZ0X00FH&pf_rd_p=edaba0ee-c2fe-4124-9f5d-b31d6b1bfbee" target="_blank" rel="noopener noreferrer">Hero's Dose: The Case For Psychedelics in Ritual and Therapy</a>."</em></p>
What makes some people more likely to shiver than others?
Some people just aren't bothered by the cold, no matter how low the temperature dips. And the reason for this may be in a person's genes.