<figure id="attachment_29593" style="width: 600px" class="wp-caption alignright"><a href="https://wp-assets.futurism.com/2014/09/Thousand-Mile-Shadow.jpg"><img class="size-full wp-image-29593" src="https://wp-assets.futurism.com/2014/09/Thousand-Mile-Shadow.jpg" alt="Image Credit: Reid Wiseman" width="600" height="398" /></a><figcaption class="wp-caption-text">Image Credit: Reid Wiseman</figcaption></figure>
This incredible picture was taken by Reid Wiseman from the International Space Station.  He <a href="https://twitter.com/astro_reid/status/506052551377436672">shared the picture</a> with the world on twitter, captioning it with &#8220;Clouds cast thousand-mile shadows into the black of space. A favorite view of ours.&#8221;
<h2>ISS: Quick Facts</h2>
<ul>
<li>It took 136 space flights to build.</li>
<li>It orbits Earth at 7.71 km/s (4.791 m/s), which is fast enough to go to the moon and return to Earth within a day.</li>
<li>It has a surface area comparable to an American football field and is similar in size to the Tantive IV, the corvette that carries Princess Leia at the start of <a href="http://en.wikipedia.org/wiki/Star_Wars_(film)">A New Hope</a>.</li>
<li>211 people, representing 15 countries, have worked on the ISS.</li>
</ul>

FromQuarkstoQuasars

This incredible picture was taken by Reid Wiseman from the International Space Station.  He shared the picture with the world on twitter, captioning it with “Clouds cast thousand-mile shadows into the black of space. A favorite view of ours.” ISS: Quick Facts It took 136 space flights to build. It orbits Earth at 7.71 km/s (4.791 […]

Clouds Cast Thousand Mile Shadows

Our universe is simply stunning. If given the chance to set out on a spaceship and explore it, most of us wouldn’t think twice. There are colorful nebulae, galaxies with billions upon billions of stars, trillions of planets, comets, asteroids, fantastic supernovae, and plenty of other celestial bodies out there—all just waiting to be discovered.
If you are an aspiring astronaut or astronomer, you should know that it&#8217;s going to be a long and arduous journey. You’ll definitely need some inspiration to keep you motivated. If you aren’t entering into either of those fields, it still doesn&#8217;t hurt to add a bit of wonder to your life. Here are some awesome images that you can use as wallpapers to keep you going.
*Note: Click the image to go to the source and download a full size image. Hover over to pause. Click right and left to advance or go back. 
<h2>Amazing Astronomy Images:</h2>
[raw][/raw]

Our universe is simply stunning. If given the chance to set out on a spaceship and explore it, most of us wouldn’t think twice. There are colorful nebulae, galaxies with billions upon billions of stars, trillions of planets, comets, asteroids, fantastic supernovae, and plenty of other celestial bodies out there—all just waiting to be discovered. […]

15 Amazing Astronomy Images

<figure id="attachment_28871" style="width: 300px" class="wp-caption alignleft"><a href="https://wp-assets.futurism.com/2014/09/Earth-Bubble-1.jpg"><img class="wp-image-28871 size-full" src="https://wp-assets.futurism.com/2014/09/Earth-Bubble-1.jpg" alt="Earth Bubble 1" width="300" height="225" /></a><figcaption class="wp-caption-text">Image via WikiMeda</figcaption></figure>
As scientists have demonstrated, our solar system seems to be a pretty special place. Namely because of us, but we aren&#8217;t the only reason. Our local neighborhood happens to lie within a region in our galaxy that is lacking in many of the things that make certain planets uninhabitable; things high energy radiation from supernovae, rogue stellar-mass black holes and densely packed regions containing hundreds, perhaps even thousands, of stars. The list goes on and on. Simply put, our solar system meets all of the requirements for Earth and everything on it to thrive.
However, that&#8217;s not to say that Earth doesn&#8217;t have its fair share of obstacles. For starters, scientists know that Earth is encased in <a title="Earth’s “Magnetic Shield” and the Van Allen Radiation Belts" href="https://futurism.com/recent-news-on-earths-van-allen-radiation-belts/" target="_blank">huge &#8220;belts&#8217; of radiation</a> that seems impossible to safely traverse. We also know that Earth is technically <a href="http://science.nasa.gov/science-news/science-at-nasa/2008/19aug_lws/" target="_blank">located within the Sun&#8217;s atmosphere</a> and that it might even be surrounded by a <a title="Dark Geology: The Mechanism of a Mystery" href="https://futurism.com/dark-geology-the-mechanism-of-a-mystery/" target="_blank">halo of dark matter </a>so large, it would make our planet look like Jupiter from afar.. that is, if we could actually see it.
Astronomers have now confirmed yet another surprising find to the list of things Earth is surrounded by.
<h1 style="padding-left: 30px; text-align: justify;">Meet The &#8220;Local Bubble:&#8221;</h1>
Long ago, physicists believed the vacuum of space to be completely empty, devoid of all types of matter. However, later research revealed that it is, in fact, pervaded with all sorts of weird things, like particles that pop in and out of existence. However, when astronomers went looking for these things in our neighborhood, they noted that, contrary to other parts of space, IT is virtually empty inside, harboring only a single atom for every liter of gas in spacetime, which raised the question: where the heck is everything?
<figure id="attachment_28872" style="width: 307px" class="wp-caption alignright"><a href="https://wp-assets.futurism.com/2014/09/Earth-Bubble-2.gif"><img class="wp-image-28872" src="https://wp-assets.futurism.com/2014/09/Earth-Bubble-2.gif" alt="Earth Bubble 2" width="307" height="266" /></a><figcaption class="wp-caption-text">Image via NASA</figcaption></figure>
Scientists went on to suggest that the reason most of the expected material is missing is because we are positioned inside of an <a href="http://phys.org/news/2014-08-evidence-supernovas-earth.html" target="_blank">immensely large bubble</a>, composed of nothing but the byproducts of one of nature&#8217;s most energetic events; <a title="Classifying Supernovae: The ‘Earth-shattering’ Kabooms" href="https://futurism.com/classifying-supernovae-the-earth-shattering-kabooms/" target="_blank">supernova explosions</a>. 
Why would they come to such a conclusion, you might ask? Well, the assertion is partially based around the discovery that, from above, Earth is being bombarded by a barrage of x-ray radiation coming at us from all sides. This radiation has since been linked to supernovae that blasted off somewhere remotely close to us in the somewhat-recent past, or about ten million years ago.
Naturally, not all astronomers agreed that the x-ray emissions were coming from dead stars, thus the local bubble was just a pretty hypothesis. In fact, more than a few scientists suggested that the bubble doesn&#8217;t exist at all and that the soft X-ray diffuse background is actually the <a href="http://www2.le.ac.uk/departments/physics/research/xroa/astrophysics-1/SWCX" target="_blank">result of charge exchanges</a>. This refers to the way in which electrically charged solar wind affects neutral gas. Through these interactions, the solar wind often robs neutral gas of its electrons. The subsequent x-ray glow looks remarkably similar to the glow left behind after a star vomits its innards up in the throes of death.
Since no consensus was reached on the issue, a team of researchers — including F. Scott Porter (from the Goddard Space Flight Center) and Massimiliano Galeazzi (a physics professor from the University of Miami in Coral Gables) — created and launched a device, called DXL (short for &#8216;<a href="http://www.nasa.gov/mission_pages/sounding-rockets/news/dxl.html" target="_blank">Diffuse X-ray Emission From the Local Galaxy</a>&#8216;),that specializes in measuring charge exchange radiation. Merely minutes after it was launched in 2012 (one of NASA&#8217;s rockets assisted in getting it about 160 miles above Earth&#8217;s surface), its objective was met, with the team learning that just 40% of this all-encompassing radiation originated from within our solar system, once again putting the bubble hypothesis back into play. 
This bubble would be 300 light-years across and shaped like a peanut (it&#8217;s extremely hot as well, with temperatures hanging around a million degrees). Under this scenario, nearby supernovae would essentially expel most of the missing ingredients generally found within &#8220;empty&#8221; space, leaving leftover radiating gas in its place (its hot diffuse gas would be the primary source of the x-ray emissions).
&#8220;This is a significant discovery,&#8221; said Galeazzi. &#8220;It affects our understanding of the area of the galaxy close to the sun, and can, therefore, be used as a foundation for future models of the galaxy structure.&#8221;
<h1 style="padding-left: 30px; text-align: justify;">Supernovae: They Are Bad For Your Health:</h1>
<figure id="attachment_28873" style="width: 300px" class="wp-caption alignleft"><a href="https://wp-assets.futurism.com/2014/09/Earth-Bubble-3.jpg"><img class="wp-image-28873 size-full" src="https://wp-assets.futurism.com/2014/09/Earth-Bubble-3.jpg" alt="Earth Bubble 3" width="300" height="255" /></a><figcaption class="wp-caption-text">Image via NASA</figcaption></figure>
The team still isn&#8217;t sure just which star is responsible for the bubble, but one of the most promising candidates is a stellar core. dubbed <a style="color: #0b0080;" title="Geminga" href="http://en.wikipedia.org/wiki/Geminga">Geminga</a> (a pulsar in the Gemini constellation). However, it&#8217;s likely that multiple stars contributed to its existence, when, as a team member put it, several stars popped off like popcorn, all happening around the same time (unusual since only a handful of supernovae ignite in every galaxy each century). Geminga itself lies about 800 light-years from Earth — a number that seems both close to us and far away at the same time — yet its effects were felt here on Earth. 
In fact, if a supernovae were to ignite within several hundred light-years of our planet, it would almost certainly <a title="Is Earth in Danger of Being Hit With a Gamma-ray Burst?" href="https://futurism.com/is-earth-in-danger-of-being-hit-with-a-gamma-ray-burst/" target="_blank">wreak untold havoc </a>on Earth. The gamma-ray beams, if their poles are pointed directly in Earth&#8217;s line of fire, would essentially destroy our ozone layer, which would, in turn, leave us vulnerable to high-energy radiation (among other things). There&#8217;s even a good chance it could wipe out all life on Earth.
All in all, supernovae are bad news for inhabited planets, but what would you expect from an event so energetic, it unleashes more energy in mere moments than the Sun will release over the course of its entire lifetime?

As scientists have demonstrated, our solar system seems to be a pretty special place. Namely because of us, but we aren’t the only reason. Our local neighborhood happens to lie within a region in our galaxy that is lacking in many of the things that make certain planets uninhabitable; things high energy radiation from supernovae, rogue stellar-mass […]

Earth is Encased In a Huge Bubble of Dead Star Guts

[iframe id=&#8221;//www.youtube.com/embed/JWncwRTMKkI&#8221;]
Check your watch. What time is it? But wait, you&#8217;ve actually been moving and accelerating, and according to Einstein, everything&#8217;s relative. So what time is it really? It all depends…
Flavor Flav knows what time it is. At least he does for Flavor Flav. Even with all his moving and accelerating, with the planet, the solar system, getting on planes, taking elevators, and perhaps even some light jogging. In the immortal words of Kool Moe Dee. Do you know what time it is?
Didn&#8217;t Einstein tell us it&#8217;s all relative? Does anyone actually know what time it is? I mean, aside from figuratively, or in a political sense, or perhaps as part of rap performance from whence the power is being fought from, requiring the sick skills of a hype man wearing a clock around his neck on a big chain.
So, after all my fancy dancing and longing for a time in rap and hip hop from days gone by, I must present to you &#8220;faithful audience member&#8221; an answer in the form of your 3 least favorite words I get to deliver.
It all depends…
<figure id="attachment_8137" style="width: 608px" class="wp-caption aligncenter"><a href="https://wp-assets.futurism.com/2013/10/Javad_alizadeh_joking-on-amazing-formula1.jpg"><img class="wp-image-8137 size-full" src="https://wp-assets.futurism.com/2013/10/Javad_alizadeh_joking-on-amazing-formula1.jpg" alt="" width="608" height="600" /></a><figcaption class="wp-caption-text">Image by Javad Alizadeh</figcaption></figure>
You have heard that everything is relative, usually we hear it from people who like to talk about &#8220;connections on many different levels&#8221;, which is just nonsense.
But in physics &#8220;everything&#8221; is relative in a very particular way. Everything is relative to the speed of light, which is the same in every reference frame. Which is confusing and repeated enough that it can become meaningless.
So I&#8217;m going to do my best to explain it. If I shine a flashlight in front of me, I will measure the beam to travel at about 300,000 km/s, which is also known as the speed of light.
And if you are moving at 200,000 km/s faster than me, and shine a flashlight ahead of you, I will see the light from your flashlight moving at the 300,000km/s. It will appear to me, as though the light from your flashlight is moving away from you at 100,000 km/s.
But when you will measure the speed of that light, relative to you, you&#8217;d think it&#8217;d be moving at 100,000 km/s as well, but instead from your perspective it will ALSO clock in at 300,000 km/s.
The speed of light. How is this even possible? It is possible in part because the rate at which you experience time relative to me changes. For you, time will seem normal, but from my perspective your time will seem slower. We agree on how fast light is moving in kilometers per second, but we disagree how long a second is. We also, by the way, disagree on the length of a meter.
This seems strange because we imagine that space and time are absolute things, and light is something that travels through space. This is our experience. Suggesting things like time and space are malleable values at best is unsettling and at worst will make us nanners from thinking too much about.
Hold on to your tinfoil hats, for it is in fact light that is the absolute, and space and time are relative to it. So what time it is depends upon your vantage point, and so there is no single absolute time.
Finally, because of relativity, each point in the Universe experiences time at a slightly different rate. For example, when we observe the cosmic microwave background, we find that we are moving at a speed of about 630 km/s relative to the background. That means we experience time a bit more slowly that something at rest relative to the cosmic background.
It&#8217;s just a tiny bit slower, but added over the entire age of the Universe, our cosmic clock is 30,000 years behind the times. Feel free to set your watch. But don&#8217;t get too precise about it. Your time could be off by tens of thousands of years.
What about you? What&#8217;s your favorite way to explain special relativity to someone? Tell us in the comments below.
<hr />
The article originally appeared on <a href="http://www.universetoday.com/" target="_blank">Universe Today</a>. It was written by Fraser Cain and is republished with permission.

[iframe id=”//www.youtube.com/embed/JWncwRTMKkI”] Check your watch. What time is it? But wait, you’ve actually been moving and accelerating, and according to Einstein, everything’s relative. So what time is it really? It all depends… Flavor Flav knows what time it is. At least he does for Flavor Flav. Even with all his moving and accelerating, with the […]

Is There An Absolute Time In The Universe?

<figure id="attachment_28859" style="width: 800px" class="wp-caption aligncenter"><a href="https://wp-assets.futurism.com/2014/09/m20m21_feynes.jpg"><img class=" wp-image-28859" src="https://wp-assets.futurism.com/2014/09/m20m21_feynes.jpg" alt="Image Credit: Lorand Fenyes" width="800" height="541" /></a><figcaption class="wp-caption-text">Image Credit: Lorand Fenyes</figcaption></figure>
Ladies and gentlemen, say hello to Messier 20 and Messier 21 (M20 and M21). The first object you noticed was probably M20, the colorful<a title="Astronomy Photo of the Day: 5/14/14 – 3 Nebulae Parade in Narrowband" href="https://futurism.com/apotd-3-nebulae-in-narrowband/"> Trifid nebula</a>. This nebula is a hot destination for amateur astronomers given the fact that it&#8217;s bright and easy to see through a small telescope. It&#8217;s located in the constellation Sagittarius, about 5,000 light-years from Earth.
The <a title="Classifications of Objects in Space: Diffuse and Star-forming Nebulae" href="https://futurism.com/classifications-of-objects-in-space-part-3-diffuse-and-star-forming-nebulae/">nebula itself is a star forming</a> region, thus it offers us keen insight into the early stages of star formation, from the beginning &#8217;embryonic&#8217; stage to the actual birth. The newly-born stars help to energize the nebula and their solar winds shape it, turning the region into this piece of cosmic art. For some scale, the dust lanes that trisect the nebula are about 40-light-years long; and about 300,000 years old. Because of this, the Trifid nebula is one of the youngest star forming regions currently known to us.
M21 is the accompanying star cluster to the upper right. It&#8217;s affectionately called &#8220;M21&#8221; because, clearly all of the really good names were already taken. M21 is also estimated to be about 5,000 light-years away, though astronomers haven&#8217;t found a connection between the two objects. M21&#8217;s stars are about 7.5-million years older than those found in M20. They just so happen to share the same region of space.

Ladies and gentlemen, say hello to Messier 20 and Messier 21 (M20 and M21). The first object you noticed was probably M20, the colorful Trifid nebula. This nebula is a hot destination for amateur astronomers given the fact that it’s bright and easy to see through a small telescope. It’s located in the constellation Sagittarius, about 5,000 light-years […]

Astronomy Photo of the Day: 09/05/14 – Messier 20 and 21

<figure id="attachment_28863" style="width: 181px" class="wp-caption alignleft"><a href="https://wp-assets.futurism.com/2014/09/Space-Plane-1.jpg"><img class="wp-image-28863" src="https://wp-assets.futurism.com/2014/09/Space-Plane-1.jpg" alt="Space Plane 1" width="181" height="126" /></a><figcaption class="wp-caption-text">Image Credit: USAF</figcaption></figure>
The United States Air Force has a secret &#8220;X-37B space plane&#8221; that is currently doing things in low-Earth orbit. The entire space plane mission sequence has been running since 2006, but the X-37B has just passed 600 days in orbit.
The shuttle is unmanned and is the third such shuttle to be flown in orbit by the USAF. Other than that, we don&#8217;t really know a lot about the program.
The X-37B was launched on December 11, 2012, and as of September 1 it has spent 630 days in orbit. Joan Johnson-Freese, who is a professor of National Security Affairs at the U.S. Naval War College said, &#8220;The Air Force continues to push the envelope of the solar-powered X-37B capabilities.&#8221; &#8211; but, again, those &#8220;capabilities&#8221; are largely a mystery.
<h2>About the Plane</h2>
<figure id="attachment_28864" style="width: 200px" class="wp-caption alignright"><a href="https://wp-assets.futurism.com/2014/09/Space-Plane-2.jpg"><img class="size-full wp-image-28864" src="https://wp-assets.futurism.com/2014/09/Space-Plane-2.jpg" alt="Image Credit: USAF" width="200" height="300" /></a><figcaption class="wp-caption-text">Image Credit: USAF</figcaption></figure>
The plane itself looks similar to the NASA space shuttle, but it&#8217;s much smaller. It&#8217;s 8.8 meters (29 ft) long, 2.9 m (9.5 ft) tall, and has a wingspan of 4.6 m (15 ft). It&#8217;s payload bay is comparable to the size of the bed in a pickup truck (for comparison, the NASA space shuttle could easily fit two X-37B spacecraft in it&#8217;s payload bay.
As referenced in  Johnson&#8217;s statement, the plane is powered by solar energy. This is one of the things that allows the plane to operate in space for so long. The plane is able to survive in space much longer than most other reusable spacecraft, though it&#8217;s still unable to compete with the longevity of other satellites, many of which are built to last decades in orbit. The only official goal the USAF has set for the X-37B is it&#8217;s intention to develop reusable space vehicle technology.
Many people have speculated about the X-37B&#8217;s &#8220;true&#8221; purpose. At minimum, it&#8217;s probably safe to assume that the USAF is testing some type of equipment or running some experiment in the payload bay of the plane (otherwise, why would they have added one?).
Before he retired, General William Shelton, who was commander of the Air Force Space Command, gave us a detailed status update about the X-37B. &#8220;I&#8217;ll give you my standard line on the X-37. It&#8217;s doing great. I can&#8217;t tell you what it&#8217;s doing, but it&#8217;s doing great.&#8221;
<a href="https://wp-assets.futurism.com/2014/09/Space-Plane-3.jpg"><img class="aligncenter size-full wp-image-28865" src="https://wp-assets.futurism.com/2014/09/Space-Plane-3.jpg" alt="Space Plane 3" width="474" height="526" /></a>
&nbsp;

The United States Air Force has a secret “X-37B space plane” that is currently doing things in low-Earth orbit. The entire space plane mission sequence has been running since 2006, but the X-37B has just passed 600 days in orbit. The shuttle is unmanned and is the third such shuttle to be flown in orbit […]

FromQuarkstoQuasars

Clouds Cast Thousand Mile Shadows

News

/ From Quarksto Quasars

ISS: Quick Facts

Keep up. Subscribe to our daily newsletter.

News

/ From Quarksto Quasars

Read This Next

FromQuarkstoQuasars

15 Amazing Astronomy Images

FromQuarkstoQuasars

Earth is Encased In a Huge Bubble of Dead Star Guts

FromQuarkstoQuasars

Is There An Absolute Time In The Universe?

FromQuarkstoQuasars

Astronomy Photo of the Day: 09/05/14 – Messier 20 and 21

FromQuarkstoQuasars

Secret U.S. Space Plane Passes 600 Days in Orbit

Next Article