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Six solar system oddities and why we must learn about them
Want some crazy space phenomena? You don't have to leave the neighborhood for it.
- The universe has a lot of weird stuff in it.
- You don't have to travel far to find it. Our solar system is filled with oddities and strangeness. Some that we can't figure out.
- Learning about these things isn't just fun, it can be applied to our lives and can alter our perspectives.
It has been said that the universe is "not only stranger than we imagine, but that it is stranger than we can imagine." John Haldane, the originator of that quote (slightly different wording according to some sources), might have been more correct than he knew. Since his death, we've discovered such exotic objects as pulsars and the cosmic background radiation. Even more out there, scientists have postulated the existence of stuff as bizarre as dark matter, dark energy, and the aptly named "strange matter."
One doesn't even need to leave the solar system to find oddities. Last week, we discussed Saturn's hexagonal storm; today, we'll look at six of the strangest things in our cosmic backyard and consider why time spent investigating them is not time wasted.
Mercury ain't what it used to be
False color image of Mercury (the yellow is water ice).
Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington
The smallest planet in the solar system constantly outdoes itself. Mercury is shrinking.
Unlike many other items on this list, this strange occurrence is likely caused by a fairly mundane mechanism. As the planet, which is made primarily of metal, has a high iron content, scientists speculate that the planet is shrinking as it continues to cool down from the high internal temperatures it had when it formed.
However, this isn't the end of things. Why Mercury has such a higher iron content remains a mystery. A leading hypothesis is that the planet used to be much larger, but that many of its non-metallic components were knocked away by an impact with a planetoid or that spikes in the sun's temperature caused much of the rocky crust of Mercury to vaporize and blow away, leaving an iron core.
You can spin faster than Venus, if you try.
As seen from Earth, the sun comes up in the east and sets in the west. On Venus, the opposite is true. This is unique among the planets of the Solar System. Even stranger, it would take 243 Earth days to be able to enjoy another sunrise if you could see it from Venus' surface. The planet only rotates at a leisurely 6.52 km/h (4.05 mph), compare that to Earth's 674.4 km/h (1,040.4 mph). For comparison, a Venusian year is only 225 Earth days, meaning a year there is shorter than a day!
The slow rotation speed causes side effects you might not have suspected. While the Earth's rotation causes the center to bulge out somewhat, Venus lacks this and is much closer to being spherical.
A variety of theories attempting to explain all this have been advanced. One argues that this results from the sun's tidal forces in battle with those created by the thick Venusian atmosphere, with the former slowing rotation and the later speeding it up. An amusing hypothesis argues that the whole planet was somehow flipped upside down, and it continues to spin in the same direction as it always has. Another suggests that a massive impact, early in the Solar System's history, knocked Venus so hard it started spinning backward.
This last theory has the bonus of explaining why Venus has no moons, as the resulting powerful tidal forces would have caused any moon there to fall into the planet.
Everything about Saturn’s moon Iapetus is odd
Images of Iapetus' mysterious ridge taken by Cassini.
For a ball of ice a little smaller than Australia, Iapetus manages to contain many odd features.
Discovered in 1671, it was immediately noticed that the moon was only visible for a few months out of the year. Astronomers at the time proposed, accurately, that the moon is tidally locked. So, only one side faces Saturn, and that one side is much, much brighter than the other. Modern discoveries show us that this is accurate, with the dark side being darker than charcoal and the light side shining like well-lit ice. It is believed that the original dark material originated from somewhere off of the moon, but that most of what we see today are lag deposits.
Over time, the heat differences (the dark side gets warmer) cause water ice to sublimate and shift location from the dark side to the light. Over vast amounts of time, this leaves one side shinning with ice and the other dark with the mineral residue the water leaves behind as it moves.
Iapetus also has the distinction of being the largest object in the solar system not in hydrostatic equilibrium, as its gravity is not strong enough to force it into a roughly spherical shape. Resultantly, it looks much more like a walnut than a ball.
Adding to the madness is how it orbits Saturn. It has a severely inclined orbit and travels much further out than the other large moons. While astronomers have no idea why this is, it gives it the advantage of being the one large moon of Saturn where an observer could enjoy a good view of Saturn's ring system.
When the Cassini probe went out of its way to examine Iapetus, it discovered the moon's walnut shape is accentuated by a dark hemisphere-spanning ridge of peaks reaching up to 20 km (12 miles) high. The light side features no ridge but does have isolated mountains with similar mass. The ridge neatly follows the moons equator with uncanny perfection. Several hypotheses have been proposed to explain the ridge, but they fail to explain why it is only present on the dark side of the moon.
Uranus is a bit crooked
If you remember anything from grade school astronomy about Uranus, it's probably that it rolls along its side like a ball while the other planets spin like tops. Its poles each spend the solstice either in full sunlight or total darkness. It is only during the equinox, when the poles are oriented perpendicular to the sun, that the entire planet has a day and night cycle similar to the other planets.
Why it rolls like this is unknown. The current leading theory involves what seems to be the favorite explanation of astronomers, a large object knocking into the planet in the early days of the solar system. As you might expect, this orientation means that Uranus's poles get more sunlight and heat than the equator does. Despite this, the equator is still warmer than the poles are. The cause of this is currently also unknown.
Neptune radiates heat. Like, a lot of heat.
A slightly retouched image of Neptune's south pole as seen by Voyager 2.
By Kevin Gill from Los Angeles, CA, United States - Neptune - August 25 1989, CC BY-SA 2.0,
The most distant known planet from the sun (sorry Pluto), Neptune gets a tiny fraction of the heat and light that other planets enjoy. It gets less than half as much sunlight as its neighbor, Uranus. As they say, though, it's what's on the inside that counts. Neptune radiates a substantial amount of heat, 2.6 times as much as it gets from the Sun, compared to Uranus' 1.1 times as much.
This internal heating provides the energy needed for Neptune to have the fastest winds in the solar system, with gusts of up to 2,100 km/h (1,300 mph) observed.
Some scientists propose the heat is just leftover from the planet's formation. Others suggest that the ice giants' internal heating might be cyclical, with Neptune and Uranus being out of sync with each other. It is also possible to view Uranus as the strange one, arguing that its internal heating is much lower than it should be. Theories that go this way often suggest that whatever knocked Uranus over took a fair amount of heat with it. The trouble with any hypothesis advanced is that it has to deal with Neptune and Uranus' apparent similarities while also allowing for this single, tremendous difference.
There is a Planet Nine, probably, maybe.
Neptune was discovered after Uranus' orbit was observed to differ from predictions in a way that suggested a large object was influencing it. Neptune was discovered orbiting almost exactly where such a large object was expected to be. Today, a similar problem exists with some objects in the Kuiper belt, leading some scientists to argue for the existence of a "Planet Nine," exerting an influence on their orbits.
Some Trans-Neptunian Objects (TNOs) have clustered orbits. Seen from above, the long ellipses that track their orbits tend to nest inside one another, with their vertexes all pointing in the same direction. Typically, we would expect these orbits to be distributed more randomly. The odds that they would be in the configuration we see them in due to chance are extremely low.
However, a planet around ten times the Earth's size in an extremely eccentric, far-flung orbit would exert a gravitational pull just strong enough to cause this and other strange phenomena observed in the Kuiper Belt.
Alternative explanations for the observed data exist. They range from the mundane proposal that what we see is coincidentally similar to what a planet would cause, to the exotic notion that we should be looking for small black holes rather than a planet. No Planet Nine has been spotted, but various studies have not yet ruled out the possibility of its existence.
Why is any of this important?
Understanding how these odd phenomena came into existence can give us a better understanding of the formation of the solar system in general and the planets in particular. Having a good idea of where something is coming from is very helpful in science, as it can make it easier to estimate where it is going.
That can be very nice to have when you're talking about the rock with odd fitting continents, exploding mountains, and an ever-evolving atmosphere floating in space you're sitting on. Beyond that, many people hope that humans will travel to other bodies in the solar system someday. It might be nice to know a bit about the strange places we might end up traveling to or some of the things we might encounter before heading out.
Even if we don't ever get to Neptune or Planet Nine, studying the odd parts of the solar system can serve as a reminder of how big and how strange the universe we live in really is. Our changing understanding of the universe has impacted how we live our lives before, and more than a few great thinkers pointed to changes in our understanding of astronomy to justify and explain their thinking in other fields.
Plus, given how many of these oddities seem related to things getting hit with giant rocks, these discoveries might help us finally get around to deciding what to do if an asteroid comes our way.
- How fast is Earth moving through space? That depends. - Big Think ›
- An Earth-sized planet found in the habitable zone of a nearby star ›
- Neil deGrasse Tyson: 3 mind-blowing space facts - Big Think ›
- Astrophysicists find rare star spinning backwards - Big Think ›
Why mega-eruptions like the ones that covered North America in ash are the least of your worries.
- 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.
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.
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.
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.
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 firstname.lastname@example.org.
How imagining the worst case scenario can help calm 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.
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.
A study on charity finds that reminding people how nice it feels to give yields better results than appealing to altruism.
- 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.
The 'Monkeydactyl' was a flying reptile that evolved highly specialized adaptations in the Mesozoic Era.