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“I left Earth three times and found no other place to go. Please take care of Spaceship Earth.” -Wally Schirra
We've made it through another amazing week here at Starts With A Bang, and what many of you might not realize is that there was a fabulous new release thanks to the support of everyone on Patreon: a new Podcast, this time on Planet Nine!
The Universe is still delivering hordes of wonder to anyone and everyone curious about it, and that's why last week saw us cover the following topics:
Why don't you look like a scientist? (for Ask Ethan),
Mars gears up for its closest…
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"Yes, now there is this technological path. But it's just starting." -Mae Jemison
Earlier this month, Yuri Milner and Stephen Hawking teamed up to announce the Breakthrough Starshot, a $100 million investment in technology that would build a laser array to propel a thin, light "laser sail" spacecraft to approximately 20% the speed of light. If we can achieve these speeds and sufficiently aim these sails at the nearest star systems, we'll arrive at our destinations within a single human lifetime.
Illustration of an exoplanetary system. Image credit: NASA/David Hardy, via astroart.org.
But…
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"We are not learning to view ourselves as an advanced, evolving civilization. That is what we really must learn to do, in due course, if we were to survive. All of that will take place, in due course, and we will be able to explore solar system. We will be able to go beyond it, provided we get our act together and learn to live as a civilization." -Edgar Mitchell
There are a great many world with opportunities for life, both in our Solar System and beyond, and we’ve only just begun to discover them. Perhaps Enceladus, Europa or Titan harbor some form of life right now, and perhaps Mars or…
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"Space is certainly something more complicated than the average person would probably realize. Space is not just an empty background in which things happen." -Alan Guth
If you go back in time, earlier and earlier, things get hotter, denser and more energetic. But there's a limit to how far back you can go, and that limit doesn't end in a singularity with the birth of time and space; instead, it ends with a period of cosmic inflation, which set up the hot Big Bang as we know it.
Image credit: National Science Foundation (NASA, JPL, Keck Foundation, Moore Foundation, related) — Funded BICEP2…
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"You cannot rob me of free nature's grace,
You cannot shut the windows of the sky
Through which Aurora shows her brightening face." -James Thomson
The northern (aurora borealis) and southern (aurora australis) lights are caused by a combination of three phenomena on our world, that make our aurorae unique among all worlds in our solar system:
Outbursts from the Sun that can go in any direction,
Our magnetic field, that funnels charged particles into circles around the poles,
And our atmospheric composition, that causes the colors and the displays we see.
Image credit: flickr user Image…
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"That’s the next step: to simultaneously see [gravitational waves] with three, four or five interferometers, localize it quickly, within minutes, and have other observatories catch it instantly, and catch it in the optical or the X-ray bands. That’s going to provide a whole new understanding in these cataclysmic events." -Dave Reitze, executive director of LIGO
On September 14th, 2015, both LIGO detectors in Hanover, WA and Livingston, LA, detected an unambiguous gravitational wave signal from two merging black holes some 1.3 billion light years distant. About 0.4 seconds later, NASA’s Fermi…
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"This is the plan. Get your ass to Mars, and go to the Hilton Hotel and flash the fake Brubaker I.D. at the front desk, that's all there is to it. Just do as I tell you." -Total Recall
Every two years, Earth passes Mars in orbit, as the inner, faster world overtakes the outer one. This year, it happens when Earth approaches aphelion, its farthest point from the Sun, while Mars approaches perihelion, or its closest approach.
Earth’s and Mars’ orbits, to scale, as viewed from the Solar System’s north direction. Image credit: Wikimedia Commons user Areong under a c.c.a.-s.a.-2.5 license.
On…
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“Not going to the Moon and banging on it with my own hammer has been the biggest disappointment in life.” -Gene Shoemaker, co-discoverer of Comet Shoemaker-Levy 9
Don't fret about your taxes here at Starts With A Bang; I'll continue to bring you the Universe for free! (Although I do take donations, and one reward you're sure to get is an early version of April's podcast, for those who don't want to wait!) If you missed anything this past week, don't be afraid to check it out now, including:
Why is Jupiter hit by so many objects in space? (for Ask Ethan),
NASA's Cassini reveals the…
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"If we cannot now end our differences, at least we can help make the world safe for diversity." -John F. Kennedy
No one likes being denied an opportunity -- or told they shouldn't do something they want to -- solely because of the way they are. That's especially true when it comes to something that's an intrinsic part of one's self, such as their race, gender, demeanor or personality. Which is why it surprised me to have my own legitimacy as a scientist questioned because of the way I choose to present myself to the world.
Image credit: J. Cummings, of Ethan Siegel in 2015.
I think it's…
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"Fundamental physics is like an art more or less. It's completely non-practical, and you can't use it for anything. But it's about the universe and how the world came into being. It's very remote from your daily life and mine, and yet it defines us as human beings." -Yuri Milner
In one of the boldest initiatives ever announced, billionaire Yuri Milner and Stephen Hawking are working on developing a "Breakthrough Starshot" project, where an advanced laser array will power a sail-driven spacecraft to speeds exceeding 60,000 km/s, taking it to the nearest stars within a single human lifetime.
A…
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"It is possible to commit no mistakes and still lose. That is not a weakness, that is life." -Jean-Luc Picard
The cosmic story common to all of us -- where we came from, how we got here and where we're headed into the future -- is both amazing and daunting. But when we're first exposed to the vastness of it all in terms of both time and space, it can be downright terrifying.
Image credit: NASA and the Hubble Heritage Team (STScI / AURA), Hubble Space Telescope / ACS.
This is particularly true for young children, who often experience a huge existential crisis when they realize that not only…
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"It's ironic: in order to observe the Sun, you need to go kilometers underground." -Art McDonald
Imagine you finally thought you understood how the Sun worked: how light elements fused into heavier ones, emitting energy in the process. And when you finally completed your calculations, you got nuclear physics results that matched what you observed exactly, energy outputs that fit, and a prediction for the emission of neutrinos.
Image credit: Wikimedia Commons user Borb, created in Inkscape, of the proton-proton chain in the Sun. Note the production of neutrinos.
Yet when you built the…
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"There was a long history of speculation that in quantum gravity, unlike Einstein's classical theory, it might be possible for the topology of spacetime to change." -Edward Witten
Quantum gravity is one of the holy grails of physics, and showing that gravitation is an inherently quantum force would be a tremendous step towards validating our present approaches to theoretical physics.
Image credit: Sabine Hossenfelder, derived from the NASA/WMAP data of the CMB.
While directly detecting gravitons might still be very far off, there are a number of weak-field tests involving the CMB and…
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"That’s all regular matter, just five percent. A quarter is “dark matter,” which is invisible and detectable only by gravitational pull, and a whopping 70 percent of the universe is made up of “dark energy,” described as a cosmic antigravity, as yet totally unknowable. It’s basically all mystery out there - all of it, with just this one sliver of knowable, livable, finite light and life." -Summer Brennan
The Universe could have had any number of fates, even given that it started out with a hot Big Bang. Gravitation could have overcome the initial expansion, eventually causing a recollapse and…
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“This then, I thought, as I looked round about me, is the representation of history. It requires a falsification of perspective. We, the survivors, see everything from above, see everything at once, and still we do not know how it was.” -W.G. Sebald
In the 1600s, the earliest telescopes saw that Saturn had "ears," while later observers all the way back then finally saw their true nature: a ringed system with complex gaps, bands and colorations throughout. Since then, Saturn’s rings have been a source of wonder and puzzlement to skywatchers everywhere. The only ring system visible…
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“I guess I have a short attention span! I'm interested in new worlds, new universes, new challenges. I always said the only reason to make a film is not for the result but for what you learn for the next one.” -Alfonso Cuarón
April has gotten off to a great start here at Starts With A Bang, with some amazing stories and some unique features you won't find anywhere else! Here's what the past week had in store:
Does the climax of the movie 'Gravity' violate simple physics? (for Ask Ethan),
LIGO's director explains what it's like to find a gravitational wave,
What do star trails…
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"An asteroid or a supervolcano could certainly destroy us, but we also face risks the dinosaurs never saw: An engineered virus, nuclear war, inadvertent creation of a micro black hole, or some as-yet-unknown technology could spell the end of us." -Elon Musk
The possibility of getting hit by a wayward asteroid or comet is a scenario that could range from an expensive inconvenience to a mass extinction-level event, depending on the mass and speed of the potential impactor. While recent events like Chelyabinsk and Tunguska -- and more energetic ones like Barringer crater and the Cretaceous-…
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"The older people that one admires seem to be fearless. They go right out into the world. It's astounding. Maybe they can't see or they can't hear, but they walk out into the street and take life as it comes. They're models of courage, in a strange way." -James Hillman
The scientific enterprise has uncovered a huge number of astounding, surprising and yet fundamental truths about our Universe, what composes it and the way it works. From the formation and evolution of life on Earth to the existence and behavior of subatomic particles to the birth of the matter and radiation filling our…
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"All truths are easy to understand once they are discovered; the point is to discover them." -Galileo Galilei
Galileo is most famous for his astronomical discoveries, including the moons of Jupiter, the existence of sunspots and the phases of Venus. These discoveries were a strong challenge to geocentrism, and his writings and debates helped popularize the heliocentric model.
Image credit: Wikimedia Commons user Fernando de Gorocica, under a c.c.a.-s.a.-3.0 license, of Galileo’s original (1610) sketches of the phases of Venus.
Yet, in a recent article for Aeon magazine, Thony Christie…
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"I'm here for several reason, Mr. Pepin, first of all for aid. When something tragic happens in our skies, we do our utmost to extend sympathy. But sympathy without action,that's an empty emotion. Mainly I'm here for the purposes of reentry."
"I don't understand."
"Adjustment," Harold said, "to earth. I'm here to make sure you didn't leave your whole life in the sky." -Adam Ross
When we launch a satellite into orbit around the Earth, we expend a tremendous amount of fuel and energy to make it happen. From hundreds of miles up -- well above the definition of space -- these satellites zip…