Tag Archives: scale

To Grasp a Billion Stars

9 Apr

Reposting another Phil Plait piece. This one is totally mindblowing.


To grasp a billion stars

There are times — rare, but they happen — when I have a difficult time describing the enormity of something. Something so big, so overwhelming, that words simply cannot suffice.

The basic story is: Using the VISTA telescope in Chile and the UKIRT telescope in Hawaii, astronomers have made an incredibly detailed map of the sky in infrared. This map will help understand our own galaxy, more distant galaxies, quasars, nebulae, and much more.

But what do I mean by “incredibly detailed”?

This is where words get hard. So hang on tight; let me show you instead.

Here’s a section of the survey they made, showing the star-forming region G305, an enormous cloud of gas about 12,000 light years away which is busily birthing tens of thousands of stars:

[Click to enstellarnate.]

Pretty, isn’t it? There are about 10,000 stars in this image, and you can see the gas and dust that’s forming new stars even as you look.

But it’s the scale of this image that’s so amazing. It’s only a tiny, tiny part of this new survey. How tiny? Well, it came from this image (the area of the first image is outlined in the white square):

Again, click to embiggen — it’ll blow your socks off. But we’re not done! That image is a subsection of this one:

… which itself is a subsection of this image:

Sure, I’ll admit that last one doesn’t look like much, squished down into a width of a few hundred pixels here for the blog. So go ahead, click on it. I dare you. If you do, you’ll get a roughly 20,000 x 2000 pixel picture of the sky, a mosaic made from thousands of individual images… and even that is grossly reduced from the original survey.

How big is the raw data from the survey? Why, it only has 150 billion pixels aiieeee aiieeeeee AIIEEEEE!!!

And this would be where I find myself lacking in adjectives. Titanic? Massive? Ginormous? These all fail utterly when trying to describe a one hundred fifty thousand megapixel picture of the sky.


And again, why worry over words when I can show you? The astronomers involved helpfully made the original data — all 150 billion pixels of it — into a pan-and-zoomable image where you can zoom in, and in, and in. It’s hypnotizing, like watching “Inception”, but made of stars.

And made of stars it is: there are over a billion stars in the original image! A billion. With a B. It’s one of the most comprehensive surveys of the sky ever made, and yet it still only scratches the surface. This survey only covers the part of the sky where the Milky Way galaxy itself is thickest — in the bottom image above you can see the edge-on disk of our galaxy plainly stretching across the entire shot — and that’s only a fraction of the entire sky.

Think on this: there are a billion stars in that image alone, but that’s less than 1% of the total number of stars in our galaxy! As deep and broad as this amazing picture is, it’s a tiny slice of our local Universe.

And once again, we’ve reached the point where I’m out of words. Our puny brains, evolved to count the number of our fingers and toes, to grasp only what’s within reach, to picture only what we can immediately see — balk at these images.

But… we took them. Human beings looked up and wondered, looked around and observed, looked out and discovered. In our quest to seek ever more knowledge, we built the tools needed to make these pictures: the telescopes, the detectors, the computers. And all along, the power behind that magnificent work was our squishy pink brains.

A billion stars in one shot, thanks to a fleshy mass of collected neurons weighing a kilogram or so. The Universe is amazing, but so are we.

Images credit: Mike Read (WFAU), UKIDSS/GPS and VVV


Empty Space

16 Nov

This whole space thing… it’s big… and it’s full of nothing at all.

I can’t actually put the code in this post, so you have to go to the link for the actual pic/scale


And you thought there was a lot of empty space in the solar system. Well, there’s even more nothing inside an atom. A hydrogen atom is only about a ten millionth of a millimeter in diameter, but the proton in the middle is a hundred thousand times smaller, and the electron whizzing around the outside is a thousand times smaller than THAT. The rest of the atom is empty. I tried to picture it, and I couldn’t. So I put together this page – and I still can’t picture it.

The page is scaled so that the smallest thing on it, the electron, is one pixel. That makes the proton, this big ball right next to us, a thousand pixels across, and the distance between them is… yep, fifty million pixels (not a hundred million, because we’re only showing the radius of the atom. ie: from the middle to the edge). If your monitor displays 72 pixels to the inch, then that works out to eleven miles – making this possibly the biggest page you’ve ever seen (I personally have seen one that was set up to be even bigger, though its exact size did not seem to represent anything specific).

I recommend trying to scroll from here to the right a screen at a time, just to see how long it takes the little thumb in the scrollbar to move visibly. True masochists can try to scroll through the whole eleven miles – but the scenery along the way is pretty bleak.

I used to think that things like rocks and buildings and my own skeleton were fairly solid. But they’re made up of atoms, and atoms, as you can see here, contain so little actual material that they can barely be said to exist.

We are all phantoms.

(Note: users of older versions of Internet Explorer may not be able to scroll manually all the way to the right edge. If you want to actually see the electron, you may need to click HERE. Oddly, for some other users, this link will not work. Hopefully there is no one for whom both are true.)

If you don’t want to actually scroll through it…

Here’s the proton.

Now… the electron is ONE PIXEL… 11 miles away.

Bonus points if you can name what that “proton” is actually a picture of.

From Discover mag…

20 Things You Didn’t Know about Nothing

1. There is vastly more nothing than something. Roughly 74 percent of the universe is “nothing,” or what physicists call dark energy; 22 percent is dark matter, particles we cannot see. Only 4 percent is baryonic matter, the stuff we call something.

2. And even something is mostly nothing. Atoms overwhelmingly consist of empty space. Matter’s solidity is an illusion caused by the electric fields created by subatomic particles.

3. There is more and more nothing every second. In 1998 astronomers measuring the expansion of the universe determined that dark energy is pushing apart the universe at an ever-accelerating speed. The discovery of nothing—and its ability to influence the fate of the cosmos—is considered the most important astronomical finding of the past decade.

4. But even nothing has a weight. The energy in dark matter is equivalent to a tiny mass; there is about one pound of dark energy in a cube of empty space 250,000 miles on each side.

5. In space, no one can hear you scream: Sound, a mechanical wave, cannot travel through a vacuum. Without matter to vibrate through, there is only silence.

6. So what if Kramer falls in a forest? Luckily, electromagnetic waves, including light and radio waves, need no medium to travel through, letting TV stations broadcast endless reruns of Seinfeld, the show about nothing.

7. Light can travel through a vacuum, but there is nothing to refract it. Alas for extraterrestrial romantics, stars do not twinkle in outer space.

8. Black holes are not holes or voids; they are the exact opposite of nothing, being the densest concentration of mass known in the universe.

9. “Zero” was first seen in cuneiform tablets written around 300 B.C. by Babylonians who used it as a placeholder (to distinguish 36 from 306 or 360, for example). The concept of zero in its mathematical sense was developed in India in the fifth century.

10. Any number divided by zero is . . . nothing, not even zero. The equation is mathematically impossible.

11. It is said that Abdülhamid II, sultan of the Ottoman Empire in the early 1900s, had censors expunge references to H2O from chemistry books because he was sure it stood for “Hamid the Second is nothing.”

12. Medieval art was mostly flat and two-dimensional until the 15th century, when the Florentine architect Filippo Brunelleschi conceived of the vanishing point, the place where parallel lines converge into nothingness. This allowed for the development of perspective in art.

13. Aristotle once wrote, “Nature abhors a vacuum,” and so did he. His complete rejection of vacuums and voids and his subsequent influence on centuries of learning prevented the adoption of the concept of zero in the Western world until around the 13th century, when Italian bankers found it to be extraordinarily useful in financial transactions.

14. Vacuums do not suck things. They create spaces into which the surrounding atmosphere pushes matter.

15. Creatio ex nihilo, the belief that the world was created out of nothing, is one of the most common themes in ancient myths and religions.

16. Current theories suggest that the universe was created out of a state of vacuum energy, that is, nothing.

17. But to a physicist there is no such thing as nothing. Empty space is instead filled with pairs of particles and antiparticles, called virtual particles, that quickly form and then, in accordance with the law of energy conservation, annihilate each other in about 10-25 second.

18. So Aristotle was right all along.

19. These virtual particles popping in and out of existence create energy. In fact, according to quantum mechanics, the energy contained in all the power plants and nuclear weapons in the world doesn’t equal the theoretical energy contained in the empty spaces between these words.

20. In other words, nothing could be the key to the theory of everything.

More food for thought re: scale of the universe

Award winning astrophotographer Thierry Legault wanted to image the Hubble Space Telescope and space shuttle Atlantis traveling together around Earth.
But how? The pair wouldn’t fly over his hometown in France during the ongoing servicing mission. To catch the rare meeting of spaceships, he decided to do some traveling of his own–all the way to Florida. Yesterday, from a location 100 kilometers south of the Kennedy Space Center, he pointed his telescope at the sun and there they were:

“I took this picture of Atlantis and HST transiting the sun on May 13th at 12:17 p.m. EDT. It was just before the shuttle reached out with its robotic arm to grapple Hubble,” says Legault. “The two spaceships were at an altitude of 600 km and they zipped across the sun in only 0.8 seconds.” He captured the split-second transit using a solar-filtered Takahashi 5-inch refracting telescope and a Canon 5D Mark II digital camera.

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