An Iridium Flare flashes over western Maine in this beautiful night sky image from June 2014. Credit and copyright: Mike Taylor/Taylor Photography.
Ever seen a flash in the night sky and wondered if you were seeing things? Iridium flares are often mistaken for meteors because of their notable bright flashes of light in the night sky but they are actually caused by a specific group of satellites that orbit our planet. The Iridium communication satellites are just in the right orbit that when sunlight reflects on their antennas, a flash — or flare — is visible down on Earth. There are currently about 66 Iridium satellites in orbit, so flares are a rather common occurrence.
This image from photographer Mike Taylor is one frame from a timelapse of the Milky Way and other features of the night sky in motion against a silhouetted foreground. “Photographed from western Maine, this shot includes quite a bit of light pollution and some fast moving cloud cover,” Mike told Universe Today via email. “Most of the light pollution in this image is coming from Farmington, Maine which is about 35 miles from this location.”
Mike added the footage from this timelapse will be featured in his upcoming short film “Shot In The Dark.”
He also provided this info about Iridium flares:
Iridium satellites are in near-polar orbits at an altitude of 485 miles. Their orbital period is approximately 100 minutes with a velocity of 16,800 miles per hour. The uniqueness of Iridium flares is that the spacecraft emits ‘flashes’ of very bright reflected light that sweep in narrow focused paths across the surface of the Earth. An Iridium communication satellite’s Main Mission Antenna is a silver-coated Teflon antenna array that mimics near-perfect mirrors and are angled at 40-degrees away from the axis of the body of the satellites. This can provide a specular reflection of the Sun’s disk, periodically causing a dazzling glint of reflected sunlight. At the Earth’s surface, the specular reflection is probably less than 50 miles wide, so each flare can only be viewed from a fairly small area. The flare duration can last from anywhere between 5 to 20 seconds and can easily be seen by the naked eye.
If you want to try and see an Iridum flare for yourself, check out Heavens Above for your location.
For this image Mike used:
Nikon D600 & 14-24 @ 14mm
f/2.8 – 30 secs – ISO 3200 – WB Kelvin 3570
06/23/14 – 11:07PM
Processed via Lightroom 5 & Photoshop CS5
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The band of the Milky Way stretches from Cygnus (left) to the Sagittarius in this wide-angle, guided photo. Credit: Bob King
Look east on a dark June night and you’ll get a face full of stars. Billions of them. With the moon now out of the sky for a couple weeks, the summer Milky Way is putting on a grand show. Some of its members are brilliant like Vega, Deneb and Altair in the Summer Triangle, but most are so far away their weak light blends into a hazy, luminous band that stretches the sky from northeast to southwest. Ever wonder just where in the galaxy you’re looking on a summer night? Down which spiral arm your gaze takes you?
Artist’s conception of the Milky Way galaxy based on the latest survey data from ESO’s VISTA telescope at the Paranal Observatory. A prominent bar of older, yellower stars lies at galaxy center surrounded by a series of spiral arms. The galaxy spans some 100,000 light years. Credit: NASA/JPL-Caltech, ESO, J. HurtTwo different perspectives on our galaxy help us better understand its shape. A face-on artist’s view at left reveals the core, spiral arms and the sun’s position. At right, we see an edge-on perspective photographed by the Cosmic Background Explorer probe. Because the sun and planets orbit in the galaxy’s plane, we’re ‘stuck’ with an edge-on view until we build a fast-enough rocket to take us above our galactic home. Credit: NASA/JPL et. all (left) and NASA
Because all stars are too far away for us to perceive depth, they appear pasted on the sky in two dimensions. We know this is only an illusion. Stars shine from every corner of the galaxy, congregating in its bar-shaped core, outer halo and along its shapely spiral arms. The trick is using your mind’s eye to see them that way.
Employing optical, infrared and radio telescopes, astronomers have mapped the broad outlines of the home galaxy, placing the sun in a minor spiral arm called the Orion or Local Arm some 26,000 light years from the galactic center. Spiral arms are named for the constellation(s) in which they appear. The grand Perseus Arm unfurls beyond our local whorl and beyond it, the Outer Arm. Peering in the direction of the galaxy’s core we first encounter the Sagittarius Arm, home to sumptuous star clusters and nebulae that make Sagittarius a favorite hunting ground for amateur astronomers.
Further in lies the massive Scutum-Centaurus Arm and finally the inner Norma Arm. Astronomers still disagree on the number of major arms and even their names, but the basic outline of the galaxy will serve as our foundation. With it, we can look out on a dark summer night at the Milky Way band and get a sense where we are in this magnificent celestial pinwheel.
The Milky Way band arches across the east and south as seen about 11:30 p.m. in mid-late June. The center of the galaxy is in the direction of the constellation Sagittarius. The dark ‘rift’ that appears to cleave the Milky Way in two is formed of clouds of interstellar dust that blocks the light of stars beyond it. Stellarium
We’ll start with the band of the Milky Way itself. Its ribbon-like form reflects the galaxy’s flattened, lens-like profile shown in the edge-on illustration above. The sun and planets are located within the galaxy’s plane (near the equator) where the stars are concentrated in a flattened disk some 100,000 light years across. When we look into the galaxy’s plane, billions of stars pile up across thousands of light years to create a narrow band of light we call the Milky Way. The same term is applied to the galaxy as a whole.
Since the average thickness of the galaxy is only about 1,000 light years, if you look above or below the band, your gaze penetrates a relatively short distance – and fewer stars – until entering intergalactic (starless) space. That why the rest of the sky outside of the Milky Way band has so few stars compared to the hordes we see within the band.
Here’s the galactic big picture showing the outline of the galaxy with constellations added. In this edge-on view, we see that the summertime Milky Way from Cassiopeia to Sagittarius includes the central bulge (in the direction of Sagittarius) and a hefty portion of one side of the flattened disk:
The outline of the Milky Way viewed edge-on is shown in gray. The yellow box includes the summer portion of the Milky Way from Cassiopeia to Scorpius with a red dot marking the galaxy’s center. This is the section we see crossing the eastern sky in June. Click to enlarge. Credit: Richard Powell with additions by the author
If you enlarge the map, you’ll see lines of galactic latitude and longitude much like those used on Earth but applied to the entire galaxy. Latitude ranges from +90 degrees at the North Galactic Pole to -90 at the South Galactic Pole. Likewise for longitude. 0 degrees latitude, o degrees longitude marks the galactic center. The summer Milky Way band extends from about longitude 340 degrees in Scorpius to 110 in Cassiopeia.
Now that we know what section of the Milky Way we peer into this time of year, let’s take an imaginary rocket journey and see it all from above:
Viewed from above, we can now see that our gaze (red arrows) reaches down the Perseus Arm (toward the constellation Cygnus) and across the Sagittarius and Scutum-Centaurus arms (toward the constellations Scutum, Sagittarius and Ophiuchus) and directly into the central bar. Interstellar dust obscures much of the center of the galaxy. Blue arrows show the direction we face during the winter months. Credit: NASA et. all with additions by the author.
Wow! The hazy arch of June’s Milky Way takes in a lot of galactic real estate. A casual look on a dark night takes us from Cassiopeia in the outer Perseus Arm across Cygnus in our Local Arm clear over to Sagittarius, the next arm in. Interstellar dust deposited by supernovae and other evolved stars obscures much of the center of the galaxy. If we could vacuum it all up, the galaxy’s center – where so many stars are concentrated – would be bright enough to cast shadows.
A view showing the summer Milky Way from mid-northern latitudes with three prominent constellations and the spiral arms we peer into when we face them. Stellarium
Here and there, there are windows or clearings in the dust cover that allow us to see star clouds in the Scutum-Centaurus and Norma Arms. In the map, I’ve also shown the section of Milky Way we face in winter. If you’ve ever compared the winter Milky Way band to the summer’s you’ve noticed it’s much fainter. I think you can see the reason why. In winter, we face away from the galaxy’s core and out into the fringes where the stars are sparser.
Look up the next dark night and contemplate the grand architecture of our home galaxy. If you close your eyes, you might almost feel it spinning.
The Milky Way over the Lake of Fire, 'Lagoa do Fogo' on the island São Miguel in the Azores in Portugal. Credit and copyright: Miguel Claro.
A gorgeous new 21-image mosaic from our of our “regulars,” Miguel Claro. Miguel explains the view:
Azores is one of the two autonomous regions of Portugal, composed of nine volcanic islands situated in the middle of the Atlantic Ocean. One of the islands is São Miguel, where we can find a beautiful lake in the crater center, called Lake of Fire, “Lagoa do Fogo”. Above it, the sky reveals the magnificent arc of our galaxy, the Milky Way, besides the light pollution coming from Vila Franca do Campo, a small town at the southern shore of the island, that illuminates the clouds near the horizon with the an orange tone. From left to right, we can see the swan (Cygnus) constellation, with its North America nebula (NGC7000) clearly visible below the Deneb star, down to the right, we can find Aquila. Sagittarius is covered by the cloud. Near the right limit, we find Scorpius and it´s super giant star, Antares, following to the right edge of the picture, it is visible the planet Saturn, in Libra.
His equipment and specs: Canon 60Da – ISO2500; 24mm at f/2; Exp. 20 secs. in 04/05/2014 at 3:45 AM.
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This simulation shows the G2 gas cloud/star during its close approach to the black hole at the center of the Milky Way. Image by ESO/MPE/Marc Schartmann.
Observatories around the world and in space have been honed-in on the center of our galaxy, looking for possible fireworks to erupt as a mystery object heads towards our galaxy’s supermassive black hole. The object – called G2 – is being watched in an intense observing campaign across all wavelengths with multiple observatories. This is the first time astronomers have been able to watch an encounter with a black hole like this in real time, and the hope is that watching G2’s demise will reveal not only what this object actually is, but also provide more information on how matter behaves near black holes and how supermassive black holes “eat” and evolve.
“We’re indeed working on new observation of G2 right now,” astronomer Leo Meyer from UCLA told Universe Today, “and we’re in a position to make a significant new statement about it very soon.”
G2 was first spotted in 2011 and was quickly deemed to be heading towards our galaxy’s supermassive black hole, called Sgr A*. Astronomers estimate G2 has a mass roughly three times that of Earth (versus the black hole, which is 4 million times the mass of our Sun). G2 is not falling directly into the black hole, but it will pass Sgr A* at about 100 times the distance between Earth and the Sun. But that’s close enough to predict that G2 is doomed for destruction.
Shown here are VLT observations from 2006, 2010 and 2013, colored blue, green and red respectively showing a gas cloud being ripped apart by the supermassive black hole at the center of the galaxy. Credit: ESO/S. Gillessen.
By last July, observations from the Very Large Telescope showed the object being stretched over more than 160 billion kilometers by the black hole’s extreme gravitational field.
Closest approach was expected to have happened by now (April 2014), but nobody’s talking publicly yet about what has been observed, although Meyer hinted news would be coming soon.
The last notification on the G2 Gas Cloud Wiki page (put together by Stefan Gillessen of the Max Planck Institute in Germany, who has lead several observing runs) was posted on April 21, 2014. This notification reported no strong flare of Sgr A* although it was around the expected time peri-center passing for G2, but there has been a rather constant radio detection of 22 GHz at that location with Japanese VLBI Network.
Northwestern University’s Daryl Haggard said in an early April 2014 press release that recent Chandra observations do not show any enhanced emissions in X-rays, adding “from the X-ray perspective, the gas cloud is late to the party, but it remains to be seen whether G2 is fashionably late or a no show.”
And that points to one question about G2: what is it exactly? Haggard called it a gas cloud, but UCLA astronomer Andrea Ghez said there’s actually a debate about what it is.
“There are two camps on that,” she told Universe Today. “Some people have suggested this is a gas cloud. But I think it’s a star. Its orbit looks so much like the orbits of other stars. There’s clearly some phenomenon that is happening, and there is some layer of gas that’s interacting because you see the tidal stretching, but that doesn’t prevent a star being in the center.”
Some astronomers argue that they aren’t seeing the amount of stretching or “spaghettification” that would be expected if this was just a cloud of gas.
Montage of simulation images showing G2 during its close approach to the black hole at the center of the Milky Way. Images by ESO/MPE/Marc Schartmann
Meyer said the stretching from the object tidally reacting to the back hole clearly points to gas, but that doesn’t tell you if something is hidden inside it or not.
“While it is getting stretched, the luminosity is staying surprisingly constant, and that is puzzling the theorists,” Meyer said.
Another puzzle is the timing of when G2’s closest approach would take place. When news of G2 first broke, it was thought that the time of closest approach to the black hole would be in mid-2013. But further observations determined that that estimate was not accurate and Spring 2014 was actually when closest approach would occur.
“This makes this year’s observations so relevant and our upcoming report significant — especially regarding the issue whether there is a star inside the cloud or not,” Meyer told Universe Today via email.
But, Ghez said, we’ll soon know the answer of what this object is.
“This is just the process of science and it’s interesting – because we’ll have a limited set of observations to find out what this is,” she said. “And it may be a gas cloud or it may be a star, but it’s pretty exciting in astronomy to have an event that everybody gets to line up and buy tickets for.”
Another question is if there actually will be any “fireworks” – as Meyer called it – when G2 meets its ultimate doom as it gets shredded and possibly eaten by the black hole. As the object approaches the black hole and gets disrupted, the gas will rain down onto the back hole, increasing the black hole’s mass, possibly making it brighter. Will this create a “flash” or possibly even a jet from the black hole?
“We don’t know, and there are a lot of uncertainties,” Meyer said at the American Astronomical Society meeting in January 2014. “This is something we haven’t seen before, and even if we don’t know if something will happen or not, it still is worth looking. It’s a unique opportunity to learn about fundamental astrophysics. Even if it’s not super-spectacular, we can still learn things.”
Meyer hinted in January that astronomers might not see much at all.
“Whatever gas might end up in the black hole might get smeared out so much that the amount of mass that gets dumped into the back might be very little,” he said. “This dietary supplement might be very little, like a pea or something!”
Our galaxy’s supermassive black hole has long been fairly inactive, but in 2013, NASA’s Swift Gamma-Ray Burst mission detected the brightest flare ever observed from Sgr A*. However, it’s not certain if this burst was related to G2 or not.
Ghez has said these observations of G2 are similar to the search for extraterrestrial life: the odds to see something are against you, but you still have to look, because if you find something, it will be spectacular.
This is exciting for astronomers, since they usually don’t get to see events like this take place “in real time.” In astrophysics, timescales of events taking place are usually very long — not over the course of several months. But it’s important to note that G2 actually met its demise around 25,000 years ago. Because of the amount of time it takes light to travel, we can only now observe this event which happened long ago.
Unfortunately, this event is beyond what amateur astronomers can observe.
“We really need to use the worlds’ most advanced observatories to observe this,” Meyer said in January, “as we have to go to multiple wavelengths and use adaptive optics since the galactic center is not visible to light in seen by our eyes, and you need a high angular resolution to see it.”
This gorgeous shot taken on April 26, 2014 is just breathtaking. “It was an epic Milky Way night,” Gavin said on Facebook.
Monument Valley one of the most majestic and most most photographed regions in the US, and is known for its dramatic landscape and mesmerizing lighting during the day — with the sun illuminating the towers and casting long shadows on the valley — but it is equally dramatic at night, too, as this image attests.
Gavin told Universe Today the video will be completed in about 2 weeks, and that he was in Arizona as an “artist in residence” at Northern Arizona University, showing the photography students some timelapse tricks on some field trips.
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Image of the Andromeda Galaxy, showing Messier 32 to the lower left, which is currently merging with Andromeda. Credit: Wikipedia Commons/Torben Hansen
In a Universe that’s expanding apart, isn’t it strange that Andromeda is actually drifting towards us? Dr. Thad Szabo from Cerritos College explains why this is happening.
“I’m Thad Szabo, and I teach astronomy and physics at Cerritos College.”
Is Andromeda drifting towards us?
“The reason that we see Andromeda moving toward us is because it’s nearby enough, and the Milky Way is massive enough and Andromeda is massive enough that they’re gravity is strong enough that there is not enough space between them that the space was able to expand and push them apart against the force of gravity. So if you take the Milky Way, all of its stars and all of its gas and dust, all of its dark matter, you’re looking at something that’s a trillion times the mass of the sun. You have the same for Andromeda, and they’re less than a mega parsec apart – to Andromeda, its about 2.2 billion light years. And so with that distance and that much mass, that’s close enough that gravity is drawing them together. Most galaxies, because they’re so distant, you do see them moving away due to the expansion of the universe.”
“But actually M81, which is about 12 million light years away, is also moving towards the Milky Way. It’s the most distant galaxy that doesn’t show red shift. So there’s enough gravity in this local group – I guess the local group is typically the Milky Way galaxy, the Andromeda galaxy, the Triangulum galaxy, and however many tens of dwarf galaxies that we’ve either discovered or haven’t discovered yet. But there’s also a bubble of about ten to twenty major size galaxies extending out to about fifteen million light years or so, and that’s kind of right on the border between where the expansion of the universe would drive things apart and where the gravity is strong enough to hold things together.”
A screen grab of the new zoomable Milky Way mosaic that uses Microsoft's WorldWide Telescope viewer. Click to use. Credit: NASA
Touring the Milky Way’s a blast with this brand new 360-degree interactive panorama. More than 2 million infrared photos taken by NASA’s Spitzer Space Telescope were jigsawed into a 20-gigapixel click-and-zoom mosaic that takes the viewer from tangled nebulae to stellar jets to blast bubbles around supergiant stars.
Magnetic loops carry gas and dust above disks of planet-forming material circling stars, as shown in this artist’s conception. These loops give off extra heat, which NASA’s Spitzer Space Telescope detects as infrared light. The colors in this illustration show what an alien observer with eyes sensitive to both visible light and infrared wavelengths might see. Credit: NASA/JPL-Caltech/R. Hurt (IPAC)
The new composite, using infrared images taken over the past decade, was compiled by a team led by UW-Madison astronomer Barbara Whitney and unveiled at a TEDactive conference in Vancouver, Canada Thursday. Unlike visual light, infrared penetrates the ubiquitous dust concentrated in the galactic plane to reveal structures otherwise obscured.
Catching a GLIMPSE of the Milky Way in this short video presentation
“For the first time, we can actually measure the large-scale structure of the galaxy using stars rather than gas,” explained Edward Churchwell, UW-Madison professor of astronomy and team co-leader. “We’ve established beyond the shadow of a doubt that our galaxy has a large bar structure that extends halfway out to the sun’s orbit. We know more about where the Milky Way’s spiral arms are.”
Named GLIMPSE360 (Galactic Legacy Mid-Plane Survey Extraordinaire project), the deep infrared survey captures only about 3% of the sky, but because it focuses on the plane of the Milky Way, where stars are most highly concentrated, it shows more than half of all the galaxy’s 300 billion suns.
The Milky Way is a spiral galaxy with several prominent arms containing stellar nurseries swathed in pink clouds of hydrogen gas. The sun is shown near the bottom in the Orion Spur. Credit: NASA
Using your imagination to hover high above the galactic plane, you’d see the Milky Way is a flat spiral galaxy sporting a stubby bar of stars crossing its central bulge. The solar system occupies a tiny niche in a minor spiral arm called the Orion Spur two-thirds of the way from the center to the edge. At 100,000 light years across, the Milky Way is vast beyond comprehension and yet it’s only one of an estimated 100 billion galaxies in the observable universe.
Bubbles of gas and sites of star formation are seen in this close up in a region in the constellation Sagittarius. Credit:
While you and I sit back and marvel at all the stellar and nebular eye candy, the Spitzer images are helping astronomers determine where the edge of the galaxy lies and location of the spiral arms. GLIMPSE images have already revealed the Milky Way to be larger than previously thought and shot through with bubbles of expanding gas and dust blown by giant stars.
Spitzer can see faint stars in the “backcountry” of our galaxy — the outer, darker regions that went largely unexplored before.
Barbara Whitney, co-leader of the GLIMPSE360 team
“There are a whole lot more lower-mass stars seen now with Spitzer on a large scale, allowing for a grand study,” said Whitney. “Spitzer is sensitive enough to pick these up and light up the entire ‘countryside’ with star formation.”
The new 360-degree view will also help NASA’s upcoming James Webb Space Telescope target the most interesting sites of star-formation, where it will make even more detailed infrared observations.
When you play around with the interactive mosaic, you’ll notice a few artifacts here and there among the images. Minor stuff. What took some getting used to was how strikingly different familiar nebulae appeared when viewed in infrared instead of visual light. The panorama is also available on the Aladin viewing platform which offers shortcuts to regions of interest.
Neil deGrasse Tyson, astrophysicist and host of the new Cosmos TV series, gave the third line of our “cosmic address” as the Milky Way after ‘Earth’ and ‘Solar System’. After a few minutes with GLIMPSE360 you’ll better appreciate the depth and breadth of our galactic home.
So many stars! A 14-image panorama taken under very dark skies in the heart of the Riverina, New South Wales, Australia, with a bit of direction from a road sign. Credit and copyright: Carlos Orue.
Which way to the center of the galaxy? This very creative — and gorgeous — view of the Milky Way was taken this past weekend (March 9, 2014) by astrophotographer Carlos Orue from Australia. Carlos said the Milky Way was so bright under these dark skies that “I almost needed sunnies to turn down the glare! Lots of green airglow visible too.” Also visible are the large and small Magallanic clouds.
While taking the images for this 14-image panorama, Carlos said he had lots of company: “Kangaroos, wallabies, wombats, emus, bunny rabbits and foxes.”
And just remember, according to Walt Disney, “That second star to the right shines in the night for you, to tell you that the dreams you plan really can come true.”
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Rise of Venus and the Milky Way in Singapore on Feb. 28, 2014. Credit and copyright: Justin Ng.
“My dream to capture the beautiful Milky Way galaxy in Singapore has finally come true this morning after the monsoon season is over,” said noted astrophotographer Justin Ng, who lives in this island country in South East Asia. Justin noted that since Singapore is known for its heavy light pollution, there are many people who believe it’s impossible to capture stars and the arc of the Milky Way under those conditions. Justin has been taking amazing deep sky and night sky photos for quite some time, but he said with this particular image he’s hoping to prove the naysayers wrong.
“Plus, I hope to inspire more astrophotographers residing in heavily light polluted city to try to capture these ‘impossible’ images,” Justin added.
UPDATE: Below is a new timelapse video from Justin Ng.
This is a single exposure shot of planet Venus and Milky Way Galaxy in Singapore. However, the light pollution near the horizon is also visible.
Justin has now created a timelapse of his Milky Way photography from the same night he took this image, and he says a timelapse like this never been attempted by any photographers in Singapore, this is is the first:
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You’ve probably heard the saying “everything’s relative”. When you consider our place in the Universe, everything really is relative. I’m recording this halfway up Vancouver Island, in the Pacific Ocean, off the West Coast of Canada. And where I’m standing is about 6,370 kilometers away from the center of the Earth, that way.
From my perspective, the Sun is over there. It’s as large as a dime held at arm’s length. For me it’s really, really far away. In fact, at this exact time it’s further away than any object I you can see with the naked eye.I’m about 150 million kilometers away from the Sun, and so are you.
We’re carving out an elliptical orbit which takes one full year to complete one whole trip around. You, me and the Earth are all located inside our Solar System. Which contains the Sun, 8 planets and a vast collection of ice, rocks and dust. We’re embedded deep within our galaxy, the Milky Way. It’s a big flat disk of stars measuring up to 120,000 light years across.
Our Solar System is located in the middle of this galactic disk. And by the middle, I mean the center of the galaxy is about 27,000 light years that way, and the edge of the galaxy is about the same distance that way.
Our Milky Way is but one galaxy in a larger collection of galaxies known as the Local Group. There are 36 known objects in the local group. Which are mostly dwarf galaxies. However, there’s also the Triangulum Galaxy, the Milky Way, and the Andromeda galaxy… which is by far the largest, most massive object in the Local Group, It’s twice the size and 4 times the mass of the Milky Way.
But where is it?
Milky Way. Image credit: NASA
From me, and you, Andromeda is located just an astronomically distant 2.5 million light years that way. Or would that be just short 2.5 million light-years that away? I’m sure you see where this is going.
The Local Group is embedded within a much larger group known as the Virgo Supercluster, containing at least 100 galaxy groups and clusters. The rough center of the supercluster is in the constellation Virgo. Which as of right now, is that way, about 65 million light years away. Which certainly makes the 2.5 million light years to Andromeda seem like an afternoon jaunt in the family car.
Unsurprisingly, The Virgo Supercluster is a part of a larger structure as well. The Pisces-Cetus Supercluster Complex. This is a vast filament of galactic superclusters measuring about 150 million light years across AND a billion light years long. The middle is just over that way. Right over there.
Andromeda Galaxy. Credit: Fabio Bortoli
One billion light years in length? Well that makes Andromeda seem right around the corner. So where are we? Where are you, and I and the Earth located in the entire Universe? The edge of the observable Universe is about 13.8 billion light years that way. But it’s also 13.8 billion light years that way. And that way, and that way.
And cosmologists think that if you travel in any direction long enough, you’ll return to your starting point, just like how you can travel in any one direction on the surface of the Earth and return right back at your starting point. In other words, the Earth is located at the very, very center of the Universe. Which sounds truly amazing.
What a strange coincidence for you and I to be located right here. Dead center. Smack dab right in the middle of the Universe. Certainly makes us sound important doesn’t it? But considering that every other spot in the Universe is also located at the center of the universe.
You heard me right. Every single spot that you can imagine inside the Universe is also the center of the Universe. That definitely complicates things in our plans for Universal relevance. And all this sure does make Andromeda seem close by….and it’s still just right over there, at the center of the Universe. Oh, and about every spot in the universe being the center of the Universe? Well, we’ll save that one for another episode.
