The moon is our closest celestial body, of course. Nevertheless, when I captured this image a few nights ago, it still took the moonlight 1.3 seconds to get here even traveling at 186,000 miles/second (300,000 km/sec).
If you think about it another way, light travels a bit less than a foot (11.3 inches) in a nanosecond. Measure the distance from switch to light and you know how long it takes the lamp to come on after you hit the button.
A little farther away, out past Mars, is Jupiter. It’s big ball of gas, much bigger than Earth and our Moon—in fact, it’s more massive than all the other planets combined (Saturn is almost as big but it’s not very dense). That big red spot on Jupiter is a storm that’s been there for years and it’s about the size of Earth.
This image was built by taking a movie, extracting over 1000 frames, selecting the best 5% using special software, and then stacking the best of the best to remove noise.
It takes light (and spacecraft radio signals) three-quarters of an hour to travel the 342,000,000 miles from Jupiter. No one will phone home if they take a vacation on a space station orbiting Jupiter when the answer to “can you hear me now” takes an hour and half!
Here’s a picture I took of our closest star, the Sun, as it looked a couple of days ago. Those blotches are sunspots, and the big ones are bigger than Earth!
It takes sunlight 8 minutes to get here. The next closest star is so far away it takes light four years to get here. Space isn’t exactly crowded.
Someone created the illustration below that provides a good size comparison, but it doesn’t accurately represent how far apart the planets are. On this scale, blue Neptune out there on the right, would be three blocks away! It takes signals four and half hours to travel the distance from Neptune.
Once in a while, an old star blows up causing what is called a nova or, if it’s a big star, a supernova. This is an image of the Rosetta Nebula that is about 5,200 light years away. The light I captured left there about the time the Stone Age ended here and early humans started making metal tools. Those tiny bright blue stars in the center are young stars that were made from the surrounding nebula.
Other supernova create clouds of gas that aren’t quite as tidy as Rosetta, but this Tarantula Nebula is beautiful because of its mess of gas and dust . It’s 160,000 light years away, and required six hours of total exposure, two minutes at a time, to pull out the details.
Some nebula remnants are very unusual. The nebula below is predominantly ionize oxygen (blue) and hydrogen (orange) gas, and is only visible with a sensitive camera and a special filter I have that isolates emissions that radiate from the gases like a florescent tube. The part at the bottom is called the Witch’s Broom. The handle of the broom, in the middle by the bright star, is about as thick as our whole solar system is wide, from Sun to former-planet Pluto.
The strange color is produced by a dual-band filter that only lets that OIII and Ha light through.
Everything I’ve shown you so far is right here in our Milky Way galaxy. When Edwin Hubble was working as a graduate student at Mt Wilson Observatory near L.A. in the 1920s he determined that the spiral cloud below wasn’t just a nebula, but a galaxy “far, far away,” as the Star Wars movie introduction put it. Those colors are what you eye would see.
The spiral above is named the Andromeda Galaxy and looks cloudy, but that haze is a trillion stars that are too small to see because this island in the sky is so far away. The light I captured took two and half million years to get here! That’s when early humans started to migrate out of Africa and began to populate the rest of the Earth.
Recently astronomers discovered there’s an unknown kind of dark matter and energy that make Andromeda and other galaxies rotate in an unexpected way. As a result, it appears as if everything we can see in the universe—you, me, moon, sun, stars, nebula—is only about 5% of what is; 95% of the Universe is invisible to us! Let that sink in!
If you were on a planet orbiting around a star over there in that galaxy and pointed your telescope back this way, our Milky Way galaxy would look similar to Andromeda—actually, a bit more like this spiral galaxy with a bright bar across the middle where stars are forming.
Galaxies come in many shapes and sizes as you can see. That little blob off to the top right in my image above, and the two blobs in the Andromeda Galaxy (second image above) are so-called dwarf galaxies made up of “just” a few million stars.
The gorgeous galaxy below, seen edge on, is a favorite. This Sombrero Galaxy, like the others, has a haze above and below the dark brim that are billions of stars that are too small to see. The dark rim is a cloud of dust and gas slowly clumping into stars and planets. I captured this image using a rented telescope, controlled over the Internet, in Chile.
Surprisingly, in our own huge Milky Way galaxy, only about seven new stars are born each year. But there are about 50 billion galaxies in the observable universe and together they create something like 400 million new stars every day. Fortunately, (unless you live near one), about the same number of stars die every day plus the universe is expanding, so we don’t have to worry about overcrowding anytime soon.
Nevertheless, those galaxies floating around out there in the great emptiness of space still manage to run into each other. It takes millions of years for the collision to occur in ultra-slow-motion because the distances are so huge, but thaty means i could capture it while it’s happening, as in this image below. It would take 30,000 years, traveling at the speed of light, to travel from the left edge to the right edge of the two galaxies.
Our Milky Way and Andromeda will collide one day. But don’t worry, it won’t happen for about 5 billion years. In any case, the Universe is very young at a mere 14.7 billion-years-old and it will be around for several trillion years. Humans, I’m not so sure what we’ll be like in a 1000 years, or even a hundred.
I don’t have any telescopes or cameras that peer into the future (yet), so this is as far as I can take you on this voyage into outer space.