Advertise here with Carbon Ads

This site is made possible by member support. ❀️

Big thanks to Arcustech for hosting the site and offering amazing tech support.

When you buy through links on kottke.org, I may earn an affiliate commission. Thanks for supporting the site!

kottke.org. home of fine hypertext products since 1998.

πŸ”  πŸ’€  πŸ“Έ  😭  πŸ•³οΈ  🀠  🎬  πŸ₯”

kottke.org posts about astronomy

A fictional flight above real Mars

Using real images of Mars taken by the HiRISE camera on the Mars Reconnaissance Orbiter, Jan FrΓΆjdman created a 3D-rendered flyover of several areas of the planet’s surface.

In this film I have chosen some locations and processed the images into panning video clips. There is a feeling that you are flying above Mars looking down watching interesting locations on the planet. And there are really great places on Mars! I would love to see images taken by a landscape photographer on Mars, especially from the polar regions. But I’m afraid I won’t see that kind of images during my lifetime.

It has really been time-consuming making these panning clips. In my 3D-process I have manually hand-picked reference points on the anaglyph image pairs. For this film I have chosen more than 33.000 reference points! It took me 3 months of calendar time working with the project every now and then.

Watch this in the highest def you can muster…gorgeous.


The Goddesses of Venus

Goddesses Of Venus Map

Last year, Eleanor Lutz made a medieval-style map of Mars. As a follow-up, she’s made a topographical map of Venus. The features on Venus are named for female mythological figures & notable women and Lutz provides a small biography for each one on the map. Among those featured on the map are:

Anne Frank
Selu (Cherokee Corn Goddess)
Kali (Hindu Goddess, Mother of Death)
Virginia Woolf
Sedna (Eskimo Whose Fingers Became Seals and Whales)
Ubastet (Egyptian Cat Goddess)
Beatrix Potter
Edith Piaf

Here are the full lists of the craters, mountains, and coronae on Venus.


An appreciation of the Hubble’s Deep Field images

More than 20 years ago, the Hubble Space Telescope took a photo of a patch of seemingly dark sky and, lo, it was filled with hundreds and hundreds of galaxies.

Hubble Ultra Deep Field

About ten years after that, they looked even deeper into the night sky and observed thousands of galaxies, each containing hundreds of billions of stars. The video above is an appreciation of these Deep Field images and what they taught us about the Universe.

In 1995, scientists pointed the Hubble Telescope at an area of the sky near the Big Dipper. The location was apparently empty, and the whole endeavour was risky β€” what, if anything, was going to show up? But what came back was nothing short of spectacular: an image of over 1,500 galaxies glimmering in a tiny sliver of the universe. Alex Hofeldt helps us understand the scale of this image.


NASA has found 7 Earth-like planets orbiting a single nearby star

Trappist 1

Today NASA announced the discovery of seven planets “that could harbor life” around a dwarf star called Trappist-1.

The planets orbit a dwarf star named Trappist-1, about 40 light years, or about 235 trillion miles, from Earth. That is quite close, and by happy accident, the orientation of the orbits of the seven planets allows them to be studied in great detail.

One or more of the exoplanets - planets around stars other than the sun - in this new system could be at the right temperature to be awash in oceans of water, astronomers said, based on the distance of the planets from the dwarf star.

“This is the first time so many planets of this kind are found around the same star,” said Michael Gillon, an astronomer at the University of Liege in Belgium and the leader of an international team that has been observing Trappist-1.

Here’s the paper published in Nature.


The Leisurely Pace of Light Speed

In a 45-minute video called Riding Light, Alphonse Swinehart animates the journey outward from the Sun to Jupiter from the perspective of a photon of light. The video underscores just how slow light is in comparison to the vast distances it has to cover, even within our own solar system. Light takes 8.5 minutes to travel from the Sun to the Earth, almost 45 minutes to Jupiter, more than 4 years to the nearest star, 100,000 years to the center of our galaxy, 2.5 million years to the nearest large galaxy (Andromeda), and 32 billion years to reach the most remote galaxy ever observed.1 The music is by Steve Reich (Music for 18 Musicians), whose music can also seem sort of endless.

If you’re impatient, you can watch this 3-minute version, sped up by 15 times:

  1. This isn’t strictly true. As I understand it, a photon that just left the Sun will never reach that most remote galaxy.↩


A beautiful aquarium supernova

Using mostly old-school visual effects β€” like ink dispersing in an aquarium and poking holes in napkins (to represent stars) β€” Thomas Vanz created a pretty compelling representation of a dying star going supernova.

Novae is a movie about an astronomical event that occurs during the last evolutionary stages of a massive star’s life, whose dramatic and catastrophic death is marked by one final titanic explosion called supernova.

By only using an aquarium, ink and water, this film is also an attempt to represent the giant with the small without any computed generated imagery.

As a tribute to Kubrick or Nolan’s filmography, Novae is a cosmic poem that want to introduce the viewer to the nebulae’s infinite beauty.

Vanz documented his process in these two videos, which are almost as entertaining as the finished product.


The Universe has 10 times more galaxies than we thought

Hubble Ultra Deep Field

A recent paper claims that the Universe has 10 times more galaxies than we previously thought: an estimated 2 trillion galaxies covering every single patch of sky visible from the Earth. But that doesn’t mean the Universe is more massive or that it contains more stars. Phil Plait explains:

Now, let me be clear. This doesn’t meant the Universe is ten times bigger than we thought, or there are ten times as many stars. I’ll explain β€” I mean, duh, it’s what I do β€” but to cut to the chase, what they found is that there are lots of teeny, faint galaxies very far away that have gone undetected. So instead of being in a smaller number of big galaxies, stars are divvied up into a bigger number of smaller ones.

So how many stars are there in the Universe? The Milky Way contains about 400 billion stars. Some massive elliptical galaxies house more than 100 trillion stars. Estimates of the total number are rough, but it’s probably around 10^24 stars…that’s a septillion stars, a trillion trillion. It’s absurd that we’d be the only planet in the Universe with life on it.


Possible Earth-like planet discovered orbiting star nearest Earth

Exoplanet Art

The scientific rumor mill is saying that astronomers in Chile have discovered an Earth-like exoplanet orbiting the star nearest Earth, Alpha Proxima, a mere 4.25 light years away. As they say, “huge if true”.

The hunt for exoplanets has been heating up in recent years. Since it began its mission in 2009, over four thousand exoplanet candidates have been discovered by the Kepler mission, several hundred of which have been confirmed to be “Earth-like” (i.e. terrestrial). And of these, some 216 planets have been shown to be both terrestrial and located within their parent star’s habitable zone (aka. “Goldilocks zone”).

But in what may prove to be the most exciting find to date, the German weekly Der Spiegel announced recently that astronomers have discovered an Earth-like planet orbiting Proxima Centauri, just 4.25 light-years away. Yes, in what is an apparent trifecta, this newly-discovered exoplanet is Earth-like, orbits within its sun’s habitable zone, and is within our reach. But is this too good to be true?

If you read the article, there’s cause for skepticism but an official announcement is coming next week so we’ll know for sure one way or the other.

The other cool thing? If there is a planet there, plans are already underway to build a project to get probes to nearby Alpha Centuri in 20 years, Project Starshot:

In the last decade and a half, rapid technological advances have opened up the possibility of light-powered space travel at a significant fraction of light speed. This involves a ground-based light beamer pushing ultra-light nanocrafts - miniature space probes attached to lightsails - to speeds of up to 100 million miles an hour. Such a system would allow a flyby mission to reach Alpha Centauri in just over 20 years from launch, and beam home images of possible planets, as well as other scientific data such as analysis of magnetic fields.

Perhaps they can redirect their target slightly?

Update: It appears as if the rumors were true. Phil Plait writing at Slate:

The planet, called Proxima Centauri b or just Proxima b (exoplanets are given their star’s name plus a lower case letter in order of discovery, starting with “b”), orbits Proxima every 11.2 days. It has a mass of no less than 1.3 times the Earth’s, so if it’s rock and metal like Earth it’s only a bit bigger. It’s a mere 7.3 million kilometers from the star-a lot closer than Earth’s distance from the Sun of 150 million kilometers!-but Proxima is so faint and cool it receives about two-thirds the amount of light and heat the Earth does. That means that it’s in Proxima’s habitable zone: It’s possible (more or less) that liquid water could exist on its surface.

That’s coooool.

Update: Project Blue wants to built a space telescope for the purpose of observing and photographing Earth-like planets around Alpha Centuri.

Project Blue is a consortium of leading space and research organizations on a mission to build and launch a small space telescope to observe planets around our nearest stellar neighbors: Alpha Centauri A and B. The goal is simple: to capture an image, visible to the human eye, of orbiting planets. Seeing a “pale blue dot” could indicate the presence of oceans or an atmosphere β€” the potential to support life. It would be our first view of another world like our own. With a modest budget and a planned launch by 2020, this goal is tantalizingly close.

Update: According to some recent observations, it seems likely that the Earth-like planet orbiting Proxima Centauri has been fried to a crisp many times by solar flares.

When they calculate the total energy of the big flare, it is ten times more powerful than one of the Sun’s bigger flares! That’s a lot of energy. So much, in fact, that the planet, Proxima b, would get good and fried by it. I mean crispy. The planet orbits the star much closer than Earth does the Sun, about 7 million kilometers from Proxima, so the energy from the flare would hit it a lot harder. Assuming these flares happen relatively often (a very safe bet), over the lifetime of the planet these would basically sandblast the planet, ripping the atmosphere right off the planet. They’d strip away any oceans, too, and sterilize whatever was left.

It’s hard to overstate the damage. These flares, over billions of years, are downright apocalyptic. It’s hard to imagine anything being able to survive. The planet may very well be a completely zapped airless lifeless ball of rock.


The Perseid meteor shower should be great this year

Perseids

Every year, the Earth moves through the debris from the Swift-Tuttle comet, resulting in the Perseid meteor shower. This year, the Earth is predicted to move through a particularly dense part of the comet’s wake, which may mean twice the number of shooting stars during this year’s shower. Here’s how to watch:

The best way to see the Perseids is to go outside between midnight and dawn on the morning of Aug. 12. Allow about 45 minutes for your eyes to adjust to the dark. Lie on your back and look straight up. Increased activity may also be seen on Aug. 12-13.

I always find these directions confusing, so to be clear: the best viewing for the Perseids is the night of Aug 11 (Thu) into the morning of Aug 12 (Fri). Good luck!


A year-long time lapse of the Earth rotating in space

NASA recently released a time lapse video of the Earth constructed from over 3000 still photographs taken over the course of a year. The photos were taken by a camera mounted on the NOAA’s DSCOVR satellite, which is perched above the Earth at Lagrange point 1.

Wait, have we talked about Lagrange points yet? Lagrange points are positions in space where the gravity of the Sun and the Earth (or between any two large things) cancel each other out. The Sun and the Earth pull equally on objects at these five points.

L1 is about a million miles from Earth directly between the Sun and Earth and anything that is placed there will hover there relative to the Earth forever (course adjustments for complicated reasons aside). It is the perfect spot for a weather satellite with a cool camera to hang out, taking photos of a never-dark Earth. In addition to DSCOVR, at least five other spacecraft have been positioned at L1.

L2 is about a million miles from the Earth directly opposite L1. The Earth always looks dark from there and it’s mostly shielded from solar radiation. Five spacecraft have lived at L2 and several more are planned, including the sequel to the Hubble Space Telescope. Turns out that the shadow of the Earth is a good place to put a telescope.

L3 is opposite the Earth from the Sun, the 6 o’clock to the Earth’s high noon. This point is less stable than the other points because the Earth’s gravitational influence is very small and other bodies (like Venus) periodically pass near enough to yank whatever’s there out, like George Clooney strolling through a country club dining room during date night.

And quoting Wikipedia, “the L4 and L5 points lie at the third corners of the two equilateral triangles in the plane of orbit whose common base is the line between the centers of the [Earth and Sun]”. No spacecraft have ever visited these points, but they are home to some interplanetary dust and asteroid 2010 TK7, which orbits around L4. Cool! (via slate)


NASA extends the missions of nine spacecraft

While we’re on the subject, NASA announced late last week that they are extending the missions of nine spacecraft sprinkled about the solar system. Included are the New Horizon probe, which will wing off to study an object in the Kuiper Belt after doing so well with Pluto and the rover Opportunity, which was slated for a mission lasting just over 90 days but has now spent more than 12 years exploring the surface of Mars.

The Dawn mission to Ceres is another spacecraft whose duration has been extended, beating long odds. Part of the spacecraft’s functionality had not been working for some time, but was recently repaired.

It was a bit unexpected because Dawn is low on fuel. “Less than a year ago, I would have thought it was ridiculous that the spacecraft would even be operating at this point,” said Marc D. Rayman, the chief engineer for the Dawn mission.

The Dawn spacecraft was designed to use four spinning wheels to pivot in different directions. But at its previous destination, the asteroid Vesta, two of the four wheels overheated and failed. At Ceres, the wheels stayed off, and the spacecraft used its thrusters instead to pivot.

In December, Dawn reached its lowest orbit, just 240 miles above Ceres. Dr. Rayman said he and his team had expected Dawn to exhaust its remaining propellant by March.

But they spun up the wheels again. That succeeded, cutting the use of the thrusters. “It all worked out beautifully,” Dr. Rayman said. That left enough fuel to contemplate doing something more.


Juno successfully enters orbit around Jupiter

After a voyage from Earth lasting almost 5 years, the Juno spacecraft successfully entered Jupiter’s orbit late last night.

The engine burn was tense. 35 minutes is a long time for a spacecraft burn; after 20 minutes it had slowed Juno enough to be in orbit, but not the correct one. It had to continue for another 15 minutes to put the spacecraft on the correct orbit. It worked essentially perfectly. The burn time was off by just one second. That will have no real effect on the orbit.

The 35-minute burn slowed Juno down by more than 1200 mph.


NASA’s Juno mission to Jupiter

Launched from Earth in August 2011, the Juno probe is due to arrive at Jupiter on July 4, 2016. Once there, it will circle Jupiter 37 times, observing its atmosphere and magnetic fields, before plunging into the giant planet so as not to contaminate Europa with microbes.

Juno’s principal goal is to understand the origin and evolution of Jupiter. Underneath its dense cloud cover, Jupiter safeguards secrets to the fundamental processes and conditions that governed our solar system during its formation. As our primary example of a giant planet, Jupiter can also provide critical knowledge for understanding the planetary systems being discovered around other stars.

With its suite of science instruments, Juno will investigate the existence of a solid planetary core, map Jupiter’s intense magnetic field, measure the amount of water and ammonia in the deep atmosphere, and observe the planet’s auroras.

Juno will let us take a giant step forward in our understanding of how giant planets form and the role these titans played in putting together the rest of the solar system.

Science is great. That video? Maybe not so much.


Gravity is the new light

Gravitational waves from two colliding black holes were first detected last September and announced in February. This week, the same science team announced a second wave detection of two smaller black holes in December.

If the first one confirmed the long-held predictions of general relativity, the new detections are a signal to get started on some all-new science.

A black hole’s gravity is so strong that even light can’t escape, so black holes are essentially impossible to see with telescopes. But they do give off gravitational waves.

“Light’s always been how we do astronomy,” Professor Jo Dunkley, an astrophysicist at Oxford University who didn’t work on the experiment, told BuzzFeed News. “Everything we know about space, we’ve got from light. This can show the stuff you can’t see with light.”

Counting black holes, combining telescope with gravitational measurements to better understand neutron stars, all the usual origin-of-the-universe stuff.

If gravitational waves don’t require cataclysmic collisions between enormous black holes for us to measure them, but can be detected on the regular, we can use them to try to figure out a whole lot more than just whether or not Einstein was totally right. That is a very nice tool to have in your pocket.


The legally blind astronomer

Tim Doucette is a legally blind astronomer. A pair of surgeries when he was younger to help improve his vision left him with a superpower: because his pupils were permanently dilated, he could see in the dark better than other people. He built an observatory and with the aid of his telescope, he can see details of far-off stars and nebula that no one else can, including UV and infrared light.


What Are the Physical Limits of Humanity?

A new video from Kurzgesagt explores the limits of human exploration in the Universe. How far can we venture? Are there limits? Turns out the answer is very much “yes”…with the important caveat “using our current understanding of physics”, which may someday provide a loophole (or wormhole, if you will). Chances are, humans will only be able to explore 0.00000000001% of the observable Universe.

This video is particularly interesting and packed with information, even by Kurzgesagt’s standards. The explanation of the Big Bang, inflation, dark matter, and expansion is concise and informative…the idea that the Universe is slowly erasing its own memory is fascinating.


Epic Time Lapse Videos of Mercury’s Transit of the Sun

About 13 times per century, the planets align in the heavens and the Earth can watch Mercury crossing the face of the Sun. NASA’s Solar Dynamics Observatory was watching too and captured time lapse videos from several angles using various instruments measuring magnetism, visible light, and UV. The cosmic ballet goes on.

See also more from the SDO: a gorgeous time lapse of the Sun, a three-year video portrait of the Sun, and Thermonuclear Art.


Mayans located their cities according to constellations

Mayan Zodiac

15-year-old Canadian William Gadoury has translated his interest in the Mayan civilization into two remarkable discoveries. Gadoury noticed that the locations of the biggest Mayan cities matched the locations of the stars in Mayan constellations. Furthermore, the star charts pointed to the existence of a previously unknown city, the ruins of which have since been uncovered by satellite photography.

“I did not understand why the Maya built their cities away from rivers, on marginal lands and in the mountains,” said Gadoury. “They had to have another reason, and as they worshiped the stars, the idea came to me to verify my hypothesis. I was really surprised and excited when I realized that the most brilliant stars of the constellations matched the largest Maya cities.”

Someone start a Kickstarter campaign so that he can visit those ruins! (via @delfuego)

Update: Due to a mislabeled file on Wikipedia, I used a photo of an Aztec compass instead of a Mayan image. I have replaced with an image of the Mayan zodiac.

Also, per my post about media coverage of science yesterday, I’ll point out quickly that there’s much to be skeptical about re: this story (see this post from a Mesoamerican archaeologist). More likely than not, there’s a Mayan scholar mailing list going bananas right now…I’ll let you know if I hear anything specific.

In the meantime, this story in the Independent contains some satellite photos of the location in question. (via @gunnihinn)

Update: Vice: That 15-Year-Old Kid Probably Didn’t Discover a Hidden Mayan City.

The rectangular feature seen on satellite is likely an old corn field (it’s not the right shape to be a pyramid). There are indeed ancient Maya sites all over the place, and satellite imagery and LiDAR are being used to discover them, but this doesn’t seem to be one of those cases…

On the bright side, the “if it sounds too good to be true, it probably is” study has been successfully replicated again. Science rolls on…


Launching a fleet of nano-probes toward nearest star

Russian billionaire Yuri Milner, with the help of Stephen Hawking and Mark Zuckerburg, plans to launch a fleet of nano-probes1 toward a star close to our solar system, Alpha Centuri. The craft, outfitted with lightsails, will be pushed along to their destination in just 20 years by powerful lasers on Earth.

In the last decade and a half, rapid technological advances have opened up the possibility of light-powered space travel at a significant fraction of light speed. This involves a ground-based light beamer pushing ultra-light nanocrafts - miniature space probes attached to lightsails - to speeds of up to 100 million miles an hour. Such a system would allow a flyby mission to reach Alpha Centauri in just over 20 years from launch, and beam home images of possible planets, as well as other scientific data such as analysis of magnetic fields.

Breakthrough Starshot aims to demonstrate proof of concept for ultra-fast light-driven nanocrafts, and lay the foundations for a first launch to Alpha Centauri within the next generation. Along the way, the project could generate important supplementary benefits to astronomy, including solar system exploration and detection of Earth-crossing asteroids.

The Atlantic and the NY Times have more information on the initiative.

  1. Sure, we can launch laser-powered nano-probes toward a distant star, but humanity still struggles with proper descriptive URLs.↩


The Backyard Astronomer

With the homemade telescope in his backyard observatory, amateur astronomer Gary Hug has discovered over 300 asteroids.


Heliocentrism vs geocentrism

Helio Vs Geo

With hindsight, it seems bloody obvious the Sun and not the Earth is the center of the solar system. Occam’s razor and all that. (via @somniumprojec)


Two Saturnian moons, lined up

Saturn Two Moons

The Cassini spacecraft took a photo of two moons of Saturn, Tethys and Enceladus, beautifully aligned with each other. The cosmic ballet goes on. (via slate)


The sizes of solar systems

As of last month, 685 multi-planet solar systems (with 1705 planets) have been discovered outside our own. This video shows the relative sizes of those systems compared to ours. Please note:

The size of the orbits are all to scale, but the size of the planets are not. For example, Jupiter is actually 11x larger than Earth, but that scale makes Earth-size planets almost invisible (or Jupiters annoyingly large).

(via @daveg)


11 years of Saturn photos from the Cassini probe

The Cassini probe, launched from Earth in 1997 (six months before I started publishing kottke.org), has been taking photos of Saturn and its moons for 11 years now. The Wall Street Journal has a great feature that shows exactly what the probe has been looking at all that time. (Note: the video above features flashing images, so beware if that sort of thing is harmful to you.)


Thermonuclear Art

In a nod to our nation’s recreational drug users, NASA has created this 30-minute ultra high-resolution look at our Sun, assembled from thousands of photographs taken by the Solar Dynamics Observatory, which snaps a 16-megapixel image of the Sun every few seconds. Duuuuuuuude…


Cassini sippin’ on Enceladus

Whoa, how have I not heard about this before today: the Cassini spacecraft is going to dive through a jet of water erupting from Enceladus, a Saturnian moon.

Discovering life was not on the agenda when Cassini was designed and launched two decades ago. Its instruments can’t capture microbes or detect life, but in a couple of dozen passes through the plumes of Enceladus, it has detected various molecules associated with life: water vapor, carbon dioxide, methane, molecular nitrogen, propane, acetylene, formaldehyde and traces of ammonia.

Wednesday’s dive will be the deepest Cassini will make through the plumes, only 30 miles above the icy surface. Scientists are especially interested in measuring the amount of hydrogen gas in the plume, which would tell them how much energy and heat are being generated by chemical reactions in hydrothermal vents at the bottom of the moon’s ocean.

That’s pretty crazy…it sounds like science fiction. NASA is doing a wonderful job producing great science with the lean budgets they are given.


The most mysterious star in the Milky Way

Astronomers are interested in the goings-on around a star in our galaxy called KIC 8462852. There appears to be a lot of debris around it, which is a bit unusual and might have any number of causes, including that an extraterrestrial intelligence built all sorts of things around the star.

Jason Wright, an astronomer from Penn State University, is set to publish an alternative interpretation of the light pattern. SETI researchers have long suggested that we might be able to detect distant extraterrestrial civilizations, by looking for enormous technological artifacts orbiting other stars. Wright and his co-authors say the unusual star’s light pattern is consistent with a “swarm of megastructures,” perhaps stellar-light collectors, technology designed to catch energy from the star.

“When [Boyajian] showed me the data, I was fascinated by how crazy it looked,” Wright told me. “Aliens should always be the very last hypothesis you consider, but this looked like something you would expect an alien civilization to build.”

Boyajian is now working with Wright and Andrew Siemion, the Director of the SETI Research Center at the University of California, Berkeley. The three of them are writing up a proposal. They want to point a massive radio dish at the unusual star, to see if it emits radio waves at frequencies associated with technological activity.

Phil Plait has more context on this weirdo star and how the alien angle is pretty far-fetched but also worth checking out.


Hand-drawn animation of 43 years of the Sun’s weather

Artist and programmer Jeff Thompson has compiled 15,000 hand-drawn maps of the Sun made by astronomers into a single video, creating a mesmerizing and delightfully makeshift stop-motion animation of the Sun’s activity over the last 43 years. Astronomers have been drawing these “solar synoptic maps” since 1956 in order to keep track of the Sun’s “weather”…sunspots, flares, and the like. (via slate)


Edward Snowden’s Fermi Paradox solution

Edward Snowden has come up with a solution to the Fermi Paradox that I hadn’t heard of before. Maybe we haven’t discovered intelligent life elsewhere in the Universe, says Snowden, because their communications encryption is indistinguishable from cosmic background radiation.

“If you look at encrypted communication, if they are properly encrypted, there is no real way to tell that they are encrypted,” Snowden said. “You can’t distinguish a properly encrypted communication from random behaviour.”

Therefore, Snowden continued, as human and alien societies get more sophisticated and move from “open communications” to encrypted communication, the signals being broadcast will quickly stop looking like recognisable signals.

“So if you have an an alien civilization trying to listen for other civilizations,” he said, “or our civilization trying to listen for aliens, there’s only one small period in the development of their society when all their communication will be sent via the most primitive and most unprotected means.”

After that, Snowden said, alien messages would be so encrypted that it would render them unrecognisable, “indistinguishable to us from cosmic microwave background radiation”. In that case, humanity would not even realise it had received such communications.

Snowden shared his hypothesis with Neil deGrasse Tyson on Tyson’s podcast, StarTalk.


Time Lapse Video of a Scale Model of the Solar System

A pair of filmmakers, Wylie Overstreet and Alex Gorosh, built a scale model of the solar system in the Nevada desert and made a time lapse of the result. For orbits, they drove their car in circles around “the Sun”. The Earth they used was the size of a marble, which made Neptune’s orbit seven miles across. (via the kid should see this)