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Scientists identify 24 planets potentially better suited for life than Earth
The study identified superhabitable planets outside of our solar system.

- The odds are that if Earth had the right conditions for the development of life, other places probably do, too.
- Scientists have identified two dozen planets that match some items on the list of desirable traits.
- All of these planets are too far away to reach with current tech, but may be valuable research targets.
It's called the "overview effect." You know, the renewed appreciation and protectiveness that astronauts orbiting the globe come to feel looking down on our precious Earth. The sense of profound awe and gratitude that we find ourselves in a place so special among the cold, vast emptiness of space. Now a study from Washington State University (WSU) says there are lots of planets out there better than this one.
Superhabitable
The 24 candidates in their habitable zone near K dwarf stars
Credit: Schulze-Makuch, et al./Astrobiology
On the other hand, all that desirable real estate is pretty far away — none of these 24 "superhabitable" planets are less than 100 light years from Earth. They were identified in a study led by geologist Dirk Schulze-Makuch of WSU and Technical University in Berlin, Germany. He was joined in the research by astrophysicists René Heller of the Max Planck Institute for Solar System Research in Germany and Edward Guinan of Villanova University.
The open-access study is published in the journal Astrobiology.
Ignoring the possibility that other planets might be even more likely to support life than ours is, after all, like someone insisting they live in the best country in the world without having visited any others. The study puts it this way: "Neglecting this possible class of 'superhabitable' planets, however, could be considered anthropocentric and geocentric biases."
In searching for superhabitable planets among the 4,500 known candidates, the scientists were not so much looking for somewhere for us to escape to as they were spotting planets that were most likely to be populated by intelligent life. Their hope is to offer up interesting targets for future investigation by instruments such as the European Space Agency's PLATO space telescope, as well as NASA's James Webb Space Telescope and LUVOIR space observatory.
Schulze-Makuch tells WSU Insider:
"With the next space telescopes coming up, we will get more information, so it is important to select some targets. We have to focus on certain planets that have the most promising conditions for complex life. However, we have to be careful to not get stuck looking for a second Earth because there could be planets that might be more suitable for life than ours."
Before one can go searching for superhabitable planets, once must figure out what that word means.
Blame it on the sun
Credit: Tungdil Preston/Unsplash
The scientists first had to work out the type of sun a superhabitable planet would be most likely to orbit. Interestingly, they decided against dwarf type G stars — also known as "dG stars" — similar to our own sun. After all, they write, "Since it took about 3.5 billion years on Earth until complex macroscopic life appeared, and about 4 billion years for technologically advanced life (us), life on many planets orbiting dG stars may simply run out of time."
Another issue is that young dG stars spin 10 times as fast as our mature Sun now does, producing "high levels of magnetic dynamo-driven activity and very intense coronal X-ray and chromospheric FUV emissions, which makes the origin and early evolution of life challenging."
The study settles on planets orbiting type K stars. These stars are a bit cooler than ours and less luminous, but they live a long time, longer than the Sun, from 20 to 70 billion years. This would give their planets more time to get life going.
Size matters
Credit: AleksandrMorrisovich/Shutterstock
Planets with a greater mass than ours were deemed desirable for a few reasons, so long as they were not so big as to become gas giants and so on. These planets would have robust, thick atmospheres, slightly higher temperatures for nurturing life, and lots of elbow room: "This would have advantages for the distribution of species and settlements of islands and continents."
Environmental requirements
Credit: BeeBright/Shutterstock
The researchers also settled on an environmental checklist for superhabitable planets. Based on the conditions that allowed life to form on Earth, a planet would have to have the following life-supporting conditions as explained in the study:
- Temperatures —"Submarine hydrothermal systems, geothermal hot springs, brine pockets in sea ice at about −30°C, deep continental areas"
- pH — "Acid mine drainage, geothermal sulfurous sites (e.g., Yellowstone) Soda lakes, peridotite-hosted hydrothermal systems (e.g., Lost City vent)"
- Water activity — "Deep-sea brines, soda lakes, evaporate ponds, dry soils and rocks, food with high solute content"
- Lower O2 content — "Anoxic marine or lacustrine sediments, intestinal organs, early Earth environments"
- Pressure — "Deep oceanic trenches such as the 11,100 m deep Marianas Trench, Martian surface conditions (based on laboratory experiments)"
- Radiation — "No natural source of radiation on Earth at levels tolerated by D. radiodurans"
- Chemical extremes — "Submarine hydrothermal vent fluids and sulfides; some high-metal containing lakes"
We have some winners. Sort of.
Of the superhabitable candidates the study detected, none totally meet the researchers' criteria, though one has four of them, meaning it may be more likely to have life on it than Earth did, and it might be a place we could consider quite comfy.
Concludes Schulze-Makuch, "It's sometimes difficult to convey this principle of superhabitable planets because we think we have the best planet. We have a great number of complex and diverse lifeforms, and many that can survive in extreme environments. It is good to have adaptable life, but that doesn't mean that we have the best of everything."
- Habitable exoplanet: Ross 128 b could support life - Big Think ›
- 10 of the strangest exoplanets in the universe - Big Think ›
- An Earth-sized planet found in the habitable zone of a nearby star ›
- There may be habitable planets all over the galaxy - Big Think ›
No, the Yellowstone supervolcano is not ‘overdue’
Why mega-eruptions like the ones that covered North America in ash are the least of your worries.
Ash deposits of some of North America's largest volcanic eruptions.
- The supervolcano under Yellowstone produced three massive eruptions over the past few million years.
- Each eruption covered much of what is now the western United States in an ash layer several feet deep.
- The last eruption was 640,000 years ago, but that doesn't mean the next eruption is overdue.
The end of the world as we know it
Panoramic view of Yellowstone National Park
Image: Heinrich Berann for the National Park Service – public domain
Of the many freak ways to shuffle off this mortal coil – lightning strikes, shark bites, falling pianos – here's one you can safely scratch off your worry list: an outbreak of the Yellowstone supervolcano.
As the map below shows, previous eruptions at Yellowstone were so massive that the ash fall covered most of what is now the western United States. A similar event today would not only claim countless lives directly, but also create enough subsidiary disruption to kill off global civilisation as we know it. A relatively recent eruption of the Toba supervolcano in Indonesia may have come close to killing off the human species (see further below).
However, just because a scenario is grim does not mean that it is likely (insert topical political joke here). In this case, the doom mongers claiming an eruption is 'overdue' are wrong. Yellowstone is not a library book or an oil change. Just because the previous mega-eruption happened long ago doesn't mean the next one is imminent.
Ash beds of North America
Ash beds deposited by major volcanic eruptions in North America.
Image: USGS – public domain
This map shows the location of the Yellowstone plateau and the ash beds deposited by its three most recent major outbreaks, plus two other eruptions – one similarly massive, the other the most recent one in North America.
Huckleberry Ridge
The Huckleberry Ridge eruption occurred 2.1 million years ago. It ejected 2,450 km3 (588 cubic miles) of material, making it the largest known eruption in Yellowstone's history and in fact the largest eruption in North America in the past few million years.
This is the oldest of the three most recent caldera-forming eruptions of the Yellowstone hotspot. It created the Island Park Caldera, which lies partially in Yellowstone National Park, Wyoming and westward into Idaho. Ash from this eruption covered an area from southern California to North Dakota, and southern Idaho to northern Texas.
Mesa Falls
About 1.3 million years ago, the Mesa Falls eruption ejected 280 km3 (67 cubic miles) of material and created the Henry's Fork Caldera, located in Idaho, west of Yellowstone.
It was the smallest of the three major Yellowstone eruptions, both in terms of material ejected and area covered: 'only' most of present-day Wyoming, Colorado, Kansas and Nebraska, and about half of South Dakota.
Lava Creek
The Lava Creek eruption was the most recent major eruption of Yellowstone: about 640,000 years ago. It was the second-largest eruption in North America in the past few million years, creating the Yellowstone Caldera.
It ejected only about 1,000 km3 (240 cubic miles) of material, i.e. less than half of the Huckleberry Ridge eruption. However, its debris is spread out over a significantly wider area: basically, Huckleberry Ridge plus larger slices of both Canada and Mexico, plus most of Texas, Louisiana, Arkansas, and Missouri.
Long Valley
This eruption occurred about 760,000 years ago. It was centered on southern California, where it created the Long Valley Caldera, and spewed out 580 km3 (139 cubic miles) of material. This makes it North America's third-largest eruption of the past few million years.
The material ejected by this eruption is known as the Bishop ash bed, and covers the central and western parts of the Lava Creek ash bed.
Mount St Helens
The eruption of Mount St Helens in 1980 was the deadliest and most destructive volcanic event in U.S. history: it created a mile-wide crater, killed 57 people and created economic damage in the neighborhood of $1 billion.
Yet by Yellowstone standards, it was tiny: Mount St Helens only ejected 0.25 km3 (0.06 cubic miles) of material, most of the ash settling in a relatively narrow band across Washington State and Idaho. By comparison, the Lava Creek eruption left a large swathe of North America in up to two metres of debris.
The difference between quakes and faults
The volume of dense rock equivalent (DRE) ejected by the Huckleberry Ridge event dwarfs all other North American eruptions. It is itself overshadowed by the DRE ejected at the most recent eruption at Toba (present-day Indonesia). This was one of the largest known eruptions ever and a relatively recent one: only 75,000 years ago. It is thought to have caused a global volcanic winter which lasted up to a decade and may be responsible for the bottleneck in human evolution: around that time, the total human population suddenly and drastically plummeted to between 1,000 and 10,000 breeding pairs.
Image: USGS – public domain
So, what are the chances of something that massive happening anytime soon? The aforementioned mongers of doom often claim that major eruptions occur at intervals of 600,000 years and point out that the last one was 640,000 years ago. Except that (a) the first interval was about 200,000 years longer, (b) two intervals is not a lot to base a prediction on, and (c) those intervals don't really mean anything anyway. Not in the case of volcanic eruptions, at least.
Earthquakes can be 'overdue' because the stress on fault lines is built up consistently over long periods, which means quakes can be predicted with a relative degree of accuracy. But this is not how volcanoes behave. They do not accumulate magma at constant rates. And the subterranean pressure that causes the magma to erupt does not follow a schedule.
What's more, previous super-eruptions do not necessarily imply future ones. Scientists are not convinced that there ever will be another big eruption at Yellowstone. Smaller eruptions, however, are much likelier. Since the Lava Creek eruption, there have been about 30 smaller outbreaks at Yellowstone, the last lava flow being about 70,000 years ago.
As for the immediate future (give or take a century): the magma chamber beneath Yellowstone is only 5 percent to 15 percent molten. Most scientists agree that is as un-alarming as it sounds. And that its statistically more relevant to worry about death by lightning, shark, or piano.
Strange Maps #1041
Got a strange map? Let me know at strangemaps@gmail.com.
Do you worry too much? Stoicism can help
How imagining the worst case scenario can help calm anxiety.
Stoicism can help overcome anxiety
- Stoicism is the philosophy that nothing about the world is good or bad in itself, and that we have control over both our judgments and our reactions to things.
- It is hardest to control our reactions to the things that come unexpectedly.
- By meditating every day on the "worst case scenario," we can take the sting out of the worst that life can throw our way.
Are you a worrier? Do you imagine nightmare scenarios and then get worked up and anxious about them? Does your mind get caught in a horrible spiral of catastrophizing over even the smallest of things? Worrying, particularly imagining the worst case scenario, seems to be a natural part of being human and comes easily to a lot of us. It's awful, perhaps even dangerous, when we do it.
But, there might just be an ancient wisdom that can help. It involves reframing this attitude for the better, and it comes from Stoicism. It's called "premeditation," and it could be the most useful trick we can learn.
Practical Stoicism
Broadly speaking, Stoicism is the philosophy of choosing your judgments. Stoics believe that there is nothing about the universe that can be called good or bad, valuable or valueless, in itself. It's we who add these values to things. As Shakespeare's Hamlet says, "There is nothing either good or bad, but thinking makes it so." Our minds color the things we encounter as being "good" or "bad," and given that we control our minds, we therefore have control over all of our negative feelings.
Put another way, Stoicism maintains that there's a gap between our experience of an event and our judgment of it. For instance, if someone calls you a smelly goat, you have an opportunity, however small and hard it might be, to pause and ask yourself, "How will I judge this?" What's more, you can even ask, "How will I respond?" We have power over which thoughts we entertain and the final say on our actions. Today, Stoicism has influenced and finds modern expression in the hugely effective "cognitive behavioral therapy."
Helping you practice StoicismCredit: Robyn Beck via Getty Images
One of the principal fathers of ancient Stoicism was the Roman statesmen, Seneca, who argued that the unexpected and unforeseen blows of life are the hardest to take control over. The shock of a misfortune can strip away the power we have to choose our reaction. For instance, being burglarized feels so horrible because we had felt so safe at home. A stomach ache, out of the blue, is harder than a stitch thirty minutes into a run. A sudden bang makes us jump, but a firework makes us smile. Fell swoops hurt more than known hardships.
What could possibly go wrong?
So, how can we resolve this? Seneca suggests a Stoic technique called "premeditatio malorum" or "premeditation." At the start of every day, we ought to take time to indulge our anxious and catastrophizing mind. We should "rehearse in the mind: exile, torture, war, shipwreck." We should meditate on the worst things that could happen: your partner will leave you, your boss will fire you, your house will burn down. Maybe, even, you'll die.
This might sound depressing, but the important thing is that we do not stop there.
Stoicism has influenced and finds modern expression in the hugely effective "cognitive behavioral therapy."
The Stoic also rehearses how they will react to these things as they come up. For instance, another Stoic (and Roman Emperor) Marcus Aurelius asks us to imagine all the mean, rude, selfish, and boorish people we'll come across today. Then, in our heads, we script how we'll respond when we meet them. We can shrug off their meanness, smile at their rudeness, and refuse to be "implicated in what is degrading." Thus prepared, we take control again of our reactions and behavior.
The Stoics cast themselves into the darkest and most desperate of conditions but then realize that they can and will endure. With premeditation, the Stoic is prepared and has the mental vigor necessary to take the blow on the chin and say, "Yep, l can deal with this."
Catastrophizing as a method of mental inoculation
Seneca wrote: "In times of peace, the soldier carries out maneuvers." This is also true of premeditation, which acts as the war room or training ground. The agonizing cut of the unexpected is blunted by preparedness. We can prepare the mind for whatever trials may come, in just the same way we can prepare the body for some endurance activity. The world can throw nothing as bad as that which our minds have already imagined.
Stoicism teaches us to embrace our worrying mind but to embrace it as a kind of inoculation. With a frown over breakfast, try to spend five minutes of your day deliberately catastrophizing. Get your anti-anxiety battle plan ready and then face the world.
Jonny Thomson teaches philosophy in Oxford. He runs a popular Instagram account called Mini Philosophy (@philosophyminis). His first book is Mini Philosophy: A Small Book of Big Ideas.
Study: People will donate more to charity if they think something’s in it for them
A study on charity finds that reminding people how nice it feels to give yields better results than appealing to altruism.
How to get people to want to give you money, literal balls of cash not gaurenteed.
- A study finds asking for donations by appealing to the donor's self-interest may result in more money than appealing to their better nature.
- Those who received an appeal to self-interest were both more likely to give and gave more than those in the control group.
- The effect was most pronounced for those who hadn't given before.
Even the best charities with the longest records of doing great fundraising work have to spend some time making sure that the next donation checks will keep coming in. One way to do this is by showing potential donors all the good things the charity did over the previous year. But there may be a better way.
A new study by researchers in the United States and Australia suggests that appealing to the benefits people will receive themselves after a donation nudges them to donate more money than appealing to the greater good.
How to get people to give away free money
The postcards that were sent to different study subjects. The one on the left highlighted benefits to the self, while the one on the right highlighted benefits to others.List et al. / Nature Human Behaviour
The study, published in Nature Human Behaviour, utilized the Pick.Click.Give program in Alaska. This program allows Alaska residents who qualify for dividends from the Alaska Permanent Fund, a yearly payment ranging from $800 to $2000 in recent years, to donate a portion of it to various in-state non-profit organizations.
The researchers randomly assigned households to either a control group or to receive a postcard in the mail encouraging them to donate a portion of their dividend to charity. That postcard could come in one of two forms, either highlighting the benefits to others or the benefits to themselves.
Those who got the postcard touting self-benefits were 6.6 percent more likely to give than those in the control group and gave 23 percent more on average. Those getting the benefits-to-others postcard were slightly more likely to give than those receiving no postcard, but their donations were no larger.
Additionally, the researchers were able to break the subject list down into a "warm list" of those who had given at least once before in the last two years and a "cold list" of those who had not. Those on the warm list, who were already giving, saw only minor increases in their likelihood to donate after getting a postcard in the mail compared to those on the cold list.
Additionally, the researchers found that warm-list subjects who received the self-interest postcard gave 11 percent more than warm-list subjects in the control group. Amazingly, among cold-list subjects, those who received a self-interest postcard gave 39 percent more.
These are substantial improvements. At the end of the study, the authors point out, "If we had sent the benefits to self message to all households in the state, aggregate contributions would have increased by nearly US$600,000."
To put this into perspective, in 2017 the total donations to the program were roughly $2,700,000.
Is altruism dead?
Are all actions inherently self-interested? Thankfully, no. The study focuses entirely on effective ways to increase charitable donations above levels that currently exist. It doesn't deny that some people are giving out of pure altruism, but rather that an appeal based on self-interest is effective. Plenty of people were giving before this study took place who didn't need a postcard as encouragement. It is also possible that some people donated part of their dividend check to a charity that does not work with Pick.Click.Give and were uncounted here.
It is also important to note that Pick.Click.Give does not provide services but instead gives money to a wide variety of organizations that do. Those organizations operate in fields from animal rescue to job training to public broadcasting. The authors note that it is possible that a more specific appeal to the benefits others will receive from a donation might prove more effective than the generic and all-inclusive "Make Alaska Better For Everyone" appeal that they used.
In an ideal world, charity is its own reward. In ours, it might help to remind somebody how warm and fuzzy they'll feel after donating to your cause.
160-million-year-old ‘Monkeydactyl’ was the first animal to develop opposable thumbs
The 'Monkeydactyl' was a flying reptile that evolved highly specialized adaptations in the Mesozoic Era.
