How fast is Earth moving through space? That depends.
We are hurtling through space. But where are we going?
Dr. Michelle Thaller is an astronomer who studies binary stars and the life cycles of stars. She is Assistant Director of Science Communication at NASA. She went to college at Harvard University, completed a post-doctoral research fellowship at the California Institute of Technology (Caltech) in Pasadena, Calif. then started working for the Jet Propulsion Laboratory's (JPL) Spitzer Space Telescope. After a hugely successful mission, she moved on to NASA's Goddard Space Flight Center (GSFC), in the Washington D.C. area. In her off-hours often puts on about 30lbs of Elizabethan garb and performs intricate Renaissance dances. For more information, visit NASA.
MICHELLE THALLER: Eugene, you've asked one of my favorite questions and a surprisingly deep one. The essence of it is: How fast are we really moving? We are a solar system; we are planets going around the Sun. But the Sun has its own motion around the galaxy, the Milky Way. And there are larger motions still because the Milky Way galaxy is also moving through space. So I'm going to try to break this down because there are a number of different ways to think about motion because when you get to these scales, one of the most important questions you have to ask is: Motion compared to what? And I'll explain that as I go along.
So one of the most easy to understand motions, but a kind of mind-blowing one is that the Sun is orbiting around the center of the Milky Way galaxy. Now, the Milky Way galaxy is a huge collection of about half a trillion stars, and it's about 100,000 light years across end-to-end. Now, we actually orbit around the center of the galaxy -- the center of the galaxy is about 30,000 light years away from us -- and we orbit around about once every 230 million years. OK, that sounds like a long time. So 230 million years to make one orbit around the galaxy. So how fast are we going? It turns out that the Sun, and us with it, it's going at about 560,000 miles an hour. That's over half a million miles an hour just around the center of our galaxy. So right now, you are moving at over half a million miles an hour around the center of the galaxy. And if you want to think about it in kind of a dramatic way, the center of the galaxy has a massive black hole at the middle, and it's about 4 million times the mass of the Sun. So right now, you are orbiting a massive black hole at half a million miles an hour. That's kind of fun.
But there are larger velocities as well. And here's where things start to get a little bit complicated because the universe is expanding. And what that really means is that space itself is expanding. It's not really correct to say the galaxies are flying through the universe with the expansion of the universe. That's actually not how it works at all. The galaxies in that sense are standing still, but the space in between them is getting bigger. It's a very strange thing to think about, but the expansion of the universe is not galaxies moving through empty space. And one of the reasons that this is important is because the farther away you look into space, the more expanding space you look through. And it's not that galaxies very far away are actually moving through space very, very fast, but they appear that way to us. There's something called the Hubble Constant, and what that means is how fast the universe is expanding for every amount of space that you look through. The Hubble constant right now is about 75 kilometers per second per megaparsec, and a megaparsec is about 3 million light years. So that means that every 3 million light years you go out, things are receding from you at an additional 75 kilometers per second. So when you're 3 million light years away, a galaxy would naturally recede away from you at 75 kilometers per second. Now double that. Say that you're now 6 million light years away, double 75: 150 kilometers per second. So for every 3 million light years you go out, you put an additional 75 kilometers per second onto the speed.
Now, that means the galaxies nearer to us are not moving very quickly at all in the natural expansion of the universe. But if you look at something billions of light years away, you're looking through that much expanding space, and it can be receding away from us, appearing to recede away from us, at a very fast velocity indeed. In fact, when you actually look at the very, very edges of the universe, things are receding away from us close to the speed of light. So that's not anything moving at the speed of light. That's just the fact that you're looking through that much expanding space that it appears to be going that fast away from you, and this is called the Hubble Law.
It took a long time for people to realize that there might be other motions besides just this expansion of the universe. And we have to tease them out because galaxies, as big as they are and as fast as they're moving, the distances they're moving across are so vast it's very difficult to detect. Over time we realized that yes indeed there were other motions besides this, what we call Hubble flow, this expansion of the universe. So we began to realize that the Milky Way galaxy was part of larger clusters of galaxies. And in some cases, clusters of galaxies were bound together by gravity, sort of orbiting around big groups of galaxies. And in other cases, these concentrations of galaxies are probably going to disperse over time as the universe expands.
So starting from relatively close to us, the closest large galaxy to us is Andromeda. And Andromeda is so big and so close that in fact, we are falling towards each other faster than the universe expanding us away. Right now the Andromeda galaxy is coming at us at a speed of about 300,000 miles an hour. And that means that's going to collide with us in a couple billion years so I wouldn't worry about that, that's not a problem for us at all. And in fact, we think the Milky Way has collided with other galaxies in the past as well. But the reason Andromeda is coming toward us is the force of gravity is accelerating us together faster than the expansion is taking it away. Other galaxies even closer to us are orbiting the Milky Way, like the Magellanic Clouds.
So now, let's go out a little bit further and think about how the Milky Way is moving through space compared to larger things. Well, the largest motion we know of right now is that we are falling in towards something called the Great Attractor. And this is a concentration of mass, a giant cluster of galaxies. And right now, we're moving at a little over one and a half million miles an hour towards that part of the sky. For a long time, we really didn't know what was there. We called it the Great Attractor because it seemed kind of mysterious. But now, we realize that it's actually the center of gravity of a huge cluster of galaxies, something called a super cluster. And this cluster probably contains over 100,000 galaxies, and it's probably on the order of about half a billion light years across. And this has been discovered only in the last few years, and it's been called the Laniakea Supercluster. Laniakea is the Hawaiian language word for the highest heaven. And this is the largest group of galaxies that we think that we are actually gravitationally associated with. We are actually falling in towards the center of this giant collection of galaxies.
So where's the Sun going? How are we moving? It depends on with respect to what. We're moving around the galaxy at half a million miles an hour. We're falling into the center of a supercluster of galaxies at one and a half million miles an hour. And all of that is superimposed on top of the expansion of the universe, which isn't really a speed, it's just that you have to look through a lot of expanding space. So there's no one answer as to how fast you're moving right now. And I think that's one of the most wonderful things is how complex these simple answers can get.
- How fast are you, planet Earth, our solar system, and the galaxy moving right now? There's no one answer to that question because we're going in several directions and multiple speeds all at the same time. How is that possible?
- Within the Milky Way galaxy, our solar system is orbiting around a massive black hole at the center of galaxy at half a million miles an hour. Separately, the Milky Way galaxy is in the Virgo Supercluster, which is falling into the Great Attractor, a huge group of galaxies called the Laniakea Supercluster, at one and a half million miles an hour.
- And all of that is superimposed on top of the natural expansion of the universe, which isn't really a speed, but is happening at 75 kilometers per second per megaparsec.
- 4 Things That Currently Break the Speed of Light Barrier - Big Think ›
- Six solar system oddities and why we learn about them - Big Think ›
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How would the ability to genetically customize children change society? Sci-fi author Eugene Clark explores the future on our horizon in Volume I of the "Genetic Pressure" series.
- A new sci-fi book series called "Genetic Pressure" explores the scientific and moral implications of a world with a burgeoning designer baby industry.
- It's currently illegal to implant genetically edited human embryos in most nations, but designer babies may someday become widespread.
- While gene-editing technology could help humans eliminate genetic diseases, some in the scientific community fear it may also usher in a new era of eugenics.
Tribalism and discrimination<p>One question the "Genetic Pressure" series explores: What would tribalism and discrimination look like in a world with designer babies? As designer babies grow up, they could be noticeably different from other people, potentially being smarter, more attractive and healthier. This could breed resentment between the groups—as it does in the series.</p><p>"[Designer babies] slowly find that 'everyone else,' and even their own parents, becomes less and less tolerable," author Eugene Clark told Big Think. "Meanwhile, everyone else slowly feels threatened by the designer babies."</p><p>For example, one character in the series who was born a designer baby faces discrimination and harassment from "normal people"—they call her "soulless" and say she was "made in a factory," a "consumer product." </p><p>Would such divisions emerge in the real world? The answer may depend on who's able to afford designer baby services. If it's only the ultra-wealthy, then it's easy to imagine how being a designer baby could be seen by society as a kind of hyper-privilege, which designer babies would have to reckon with. </p><p>Even if people from all socioeconomic backgrounds can someday afford designer babies, people born designer babies may struggle with tough existential questions: Can they ever take full credit for things they achieve, or were they born with an unfair advantage? To what extent should they spend their lives helping the less fortunate? </p>
Sexuality dilemmas<p>Sexuality presents another set of thorny questions. If a designer baby industry someday allows people to optimize humans for attractiveness, designer babies could grow up to find themselves surrounded by ultra-attractive people. That may not sound like a big problem.</p><p>But consider that, if designer babies someday become the standard way to have children, there'd necessarily be a years-long gap in which only some people are having designer babies. Meanwhile, the rest of society would be having children the old-fashioned way. So, in terms of attractiveness, society could see increasingly apparent disparities in physical appearances between the two groups. "Normal people" could begin to seem increasingly ugly.</p><p>But ultra-attractive people who were born designer babies could face problems, too. One could be the loss of body image. </p><p>When designer babies grow up in the "Genetic Pressure" series, men look like all the other men, and women look like all the other women. This homogeneity of physical appearance occurs because parents of designer babies start following trends, all choosing similar traits for their children: tall, athletic build, olive skin, etc. </p><p>Sure, facial traits remain relatively unique, but everyone's more or less equally attractive. And this causes strange changes to sexual preferences.</p><p>"In a society of sexual equals, they start looking for other differentiators," he said, noting that violet-colored eyes become a rare trait that genetically engineered humans find especially attractive in the series.</p><p>But what about sexual relationships between genetically engineered humans and "normal" people? In the "Genetic Pressure" series, many "normal" people want to have kids with (or at least have sex with) genetically engineered humans. But a minority of engineered humans oppose breeding with "normal" people, and this leads to an ideology that considers engineered humans to be racially supreme. </p>
Regulating designer babies<p>On a policy level, there are many open questions about how governments might legislate a world with designer babies. But it's not totally new territory, considering the West's dark history of eugenics experiments.</p><p>In the 20th century, the U.S. conducted multiple eugenics programs, including immigration restrictions based on genetic inferiority and forced sterilizations. In 1927, for example, the Supreme Court ruled that forcibly sterilizing the mentally handicapped didn't violate the Constitution. Supreme Court Justice Oliver Wendall Holmes wrote, "… three generations of imbeciles are enough." </p><p>After the Holocaust, eugenics programs became increasingly taboo and regulated in the U.S. (though some states continued forced sterilizations <a href="https://www.uvm.edu/~lkaelber/eugenics/" target="_blank">into the 1970s</a>). In recent years, some policymakers and scientists have expressed concerns about how gene-editing technologies could reanimate the eugenics nightmares of the 20th century. </p><p>Currently, the U.S. doesn't explicitly ban human germline genetic editing on the federal level, but a combination of laws effectively render it <a href="https://academic.oup.com/jlb/advance-article/doi/10.1093/jlb/lsaa006/5841599#204481018" target="_blank" rel="noopener noreferrer">illegal to implant a genetically modified embryo</a>. Part of the reason is that scientists still aren't sure of the unintended consequences of new gene-editing technologies. </p><p>But there are also concerns that these technologies could usher in a new era of eugenics. After all, the function of a designer baby industry, like the one in the "Genetic Pressure" series, wouldn't necessarily be limited to eliminating genetic diseases; it could also work to increase the occurrence of "desirable" traits. </p><p>If the industry did that, it'd effectively signal that the <em>opposites of those traits are undesirable. </em>As the International Bioethics Committee <a href="https://academic.oup.com/jlb/advance-article/doi/10.1093/jlb/lsaa006/5841599#204481018" target="_blank" rel="noopener noreferrer">wrote</a>, this would "jeopardize the inherent and therefore equal dignity of all human beings and renew eugenics, disguised as the fulfillment of the wish for a better, improved life."</p><p><em>"Genetic Pressure Volume I: Baby Steps"</em><em> by Eugene Clark is <a href="http://bigth.ink/38VhJn3" target="_blank">available now.</a></em></p>
We look back at a year ravaged by a global pandemic, economic downturn, political turmoil and the ever-worsening climate crisis.
Billions are at risk of missing out on the digital leap forward, as growing disparities challenge the social fabric.
Image: Global Risks Report 2021<h3>Widespread effects</h3><p>"The immediate human and economic costs of COVID-19 are severe," the report says. "They threaten to scale back years of progress on reducing global poverty and inequality and further damage social cohesion and global cooperation."</p><p>For those reasons, the pandemic demonstrates why infectious diseases hits the top of the impact list. Not only has COVID-19 led to widespread loss of life, it is holding back economic development in some of the poorest parts of the world, while amplifying wealth inequalities across the globe.</p><p>At the same time, there are concerns the fight against the pandemic is taking resources away from other critical health challenges - including a <a href="https://www.weforum.org/agenda/2020/09/charts-covid19-malnutrition-educaion-mental-health-children-world/" target="_blank" rel="noopener noreferrer">disruption to measles vaccination programmes</a>.</p>
A new study explains how a chaotic region just outside a black hole's event horizon might provide a virtually endless supply of energy.
- In 1969, the physicist Roger Penrose first proposed a way in which it might be possible to extract energy from a black hole.
- A new study builds upon similar ideas to describe how chaotic magnetic activity in the ergosphere of a black hole may produce vast amounts of energy, which could potentially be harvested.
- The findings suggest that, in the very distant future, it may be possible for a civilization to survive by harnessing the energy of a black hole rather than a star.
The ergosphere<p>The ergosphere is a region just outside a black hole's event horizon, the boundary of a black hole beyond which nothing, not even light, can escape. But light and matter just outside the event horizon, in the ergosphere, would also be affected by the immense gravity of the black hole. Objects in this zone would spin in the same direction as the black hole at incredibly fast speeds, similar to objects floating around the center of a whirlpool.</p><p>The Penrose process states, in simple terms, that an object could enter the ergosphere and break into two pieces. One piece would head toward the event horizon, swallowed by the black hole. But if the other piece managed to escape the ergosphere, it could emerge with more energy than it entered with.</p><p>The movie "Interstellar" provides an example of the Penrose process. Facing a fuel shortage on a deep-space mission, the crew makes a last-ditch effort to return home by entering the ergosphere of a blackhole, ditching part of their spacecraft, and "slingshotting" away from the black hole with vast amounts of energy.</p><p>In a recent study published in the American Physical Society's <a href="https://journals.aps.org/prd/abstract/10.1103/PhysRevD.103.023014" target="_blank" style="">Physical Review D</a><em>, </em>physicists Luca Comisso and Felipe A. Asenjo used similar ideas to describe another way energy could be extracted from a black hole. The idea centers on the magnetic fields of black holes.</p><p style="margin-left: 20px;">"Black holes are commonly surrounded by a hot 'soup' of plasma particles that carry a magnetic field," Comisso, a research scientist at Columbia University and lead study author, told <a href="https://news.columbia.edu/energy-particles-magnetic-fields-black-holes" target="_blank" rel="noopener noreferrer">Columbia News</a>.</p>
Event Horizon Telescope Collaboration<p>While there might not be immediate applications for the theory, it could help scientists better understand and observe black holes. On an abstract level, the findings may expand the limits of what scientists imagine is possible in deep space.</p><p style="margin-left: 20px;">"Thousands or millions of years from now, humanity might be able to survive around a black hole without harnessing energy from stars," Comisso said. "It is essentially a technological problem. If we look at the physics, there is nothing that prevents it."</p>
The father of all giant sea bugs was recently discovered off the coast of Java.
- A new species of isopod with a resemblance to a certain Sith lord was just discovered.
- It is the first known giant isopod from the Indian Ocean.
- The finding extends the list of giant isopods even further.
The ocean depths are home to many creatures that some consider to be unnatural.<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMzU2NzY4My9vcmlnaW4ucG5nIiwiZXhwaXJlc19hdCI6MTYxNTUwMzg0NX0.BTK3zVeXxoduyvXfsvp4QH40_9POsrgca_W5CQpjVtw/img.png?width=980" id="b6fb0" class="rm-shortcode" data-rm-shortcode-id="2739ec50d9f9a3bd0058f937b6d447ac" data-rm-shortcode-name="rebelmouse-image" data-width="1512" data-height="2224" />
What benefit does this find have for science? And is it as evil as it looks?<div class="rm-shortcode" data-media_id="7XqcvwWp" data-player_id="FvQKszTI" data-rm-shortcode-id="8506fcd195866131efb93525ae42dec4"> <div id="botr_7XqcvwWp_FvQKszTI_div" class="jwplayer-media" data-jwplayer-video-src="https://content.jwplatform.com/players/7XqcvwWp-FvQKszTI.js"> <img src="https://cdn.jwplayer.com/thumbs/7XqcvwWp-1920.jpg" class="jwplayer-media-preview" /> </div> <script src="https://content.jwplatform.com/players/7XqcvwWp-FvQKszTI.js"></script> </div> <p>The discovery of a new species is always a cause for celebration in zoology. That this is the discovery of an animal that inhabits the deeps of the sea, one of the least explored areas humans can get to, is the icing on the cake.</p><p>Helen Wong of the National University of Singapore, who co-authored the species' description, explained the importance of the discovery:</p><p>"The identification of this new species is an indication of just how little we know about the oceans. There is certainly more for us to explore in terms of biodiversity in the deep sea of our region." </p><p>The animal's visual similarity to Darth Vader is a result of its compound eyes and the curious shape of its <a href="https://lkcnhm.nus.edu.sg/research/sjades2018/" target="_blank" rel="noopener noreferrer dofollow" style="">head</a>. However, given the location of its discovery, the bottom of the remote seas, it may be associated with all manner of horrifically evil Elder Things and <a href="https://en.wikipedia.org/wiki/Cthulhu" target="_blank" rel="dofollow">Great Old Ones</a>. <em></em></p>
A popular and longstanding wave of thought in psychology and psychotherapy is that diagnosis is not relevant for practitioners in those fields.