These New Rubin Observatory Images Are More Important Than They Look

The Vera C. Rubin Observatory is changing astronomy forever. It has an extraordinary mission. To image the night sky over and over again. Every night for the next 10 years. These images that we already have give us an idea of what this is going to look like. For example, this is Rubin's Ocean of Stars. This is a tantalizing preview of what's to come, a preview of what Rubin can do. This is a stunning image, but the Observatory is going to do so much more than just this. The Rubin Observatory wasn't built to take individual pictures like this. It was built to watch the universe change, to capture the dynamic sky and the dynamic universe. And now, after years of construction, testing, and of course delays, Rubin's 10-year survey of the sky has begun. The telescope has an enormous 8.4-metre primary mirror and a unique design, and it will use this to do some amazing things. At its heart is the largest digital camera ever built. It's roughly the size of a small car, weighs over three tons, and packs a staggering 3.2 billion pixels. It's surveying the entire southern sky from on top of a mountain in Chile. More than the pictures though, it's going to create an ultra-wide, ultra-high definition movie of the night sky. And along the way, we'll discover millions of asteroids and supernovae, as well as seeing many distant galaxies for the first time in history. The amount of data it will collect each year will be staggering too. In its first year alone, Rubin will collect more data than all other optical telescopes on the ground and in space combined. This picture, released to sort of tease us for what's to come, is called the Ocean of Stars. It's a 1.7 billion pixel image of a region in the Lupus constellation. The full thing is higher resolution than our eyes can even process. And of course YouTube can't show it at even close to full resolution. So there are links in the description if you want to try it on your own machine and screen. The picture contains millions of multicolored stars against a backdrop of galaxies of all shapes and sizes, some of which are being imaged here for the very first time. The brightest stars punctuate the scene in dazzling blue, yellow, reds and whites. We're peering close to the Milky Way's plane. It's a crowded, glittering view of our home galaxy. If we look carefully though, we can notice something else. There are these incredibly faint, ghostly, wispy structures running through the image. These are clouds of interstellar dust in our own Milky Way. They're sometimes referred to as galactic cirrus, and other telescopes like Euclid have imaged them too. Rubin is sensitive enough to reveal these incredibly faint structures across a huge area of the sky. The ocean of stars we're looking at isn't from the main survey. Known as the Legacy Survey of Space and Time, or LSST. This was released to celebrate the beginning of that survey, but was taken before the survey itself started. While this early test shot came from commissioning, images like the cosmos field that we'll look at later mark the very first official data releases right as the main survey launched. Around the brightest stars here, we can see these pretty spectacular spikes radiating out from them. Of course, they aren't real giant structures around the stars, they're something called diffraction spikes, an optical effect produced when the light from bright stars interacts with the physical structures around Rubin's telescope, including the supports for its secondary mirror. Since Rubin observes through different filters, those effects produce some beautiful colors in the finished image. But it's important to remember they aren't real structures, they're just an artifact from the telescope itself. However, the really important thing about this image isn't any individual star or dust cloud. It's seeing the sheer amount of sky that Rubin can see at once. Because its camera contains 3.2 billion pixels, the telescope is designed to cover an enormous area of sky in every single exposure. Each one can see an area about 40 times the size of the full moon. That means Rubin doesn't have to spend days staring at one tiny patch of the universe. It can take an enormous picture, move on, take another, move on again, and take another one, and so on and so on. And then it comes back to do it all again, by imaging the entire southern sky over and over again. Rubin can see what stays the same, but more importantly, it can see what changes in the sky. Asteroids can move, stars can brighten and dim, other stars may explode as supernovae, and even distant black holes might get brighter as they feed. Beyond this, we can even see completely unexpected things, and those possibilities are probably the most exciting discoveries that Rubin will make. That's the fundamental idea behind LSST. Rubin is going to repeatedly survey enormous areas of sky and turn those observations into a time lapse of the entire universe. That I cannot wait to see. The next image we can talk about already though becomes really interesting, because it looks quite different to the ocean of stars we just saw. Here there aren't nearly as many bright stars, but instead the image is packed full of galaxies. This is how Rubin sees a pretty well-known patch of sky called the cosmos field. We can see over 650,000 galaxies in this picture, plus about 75,000 stars that are in our own Milky Way. These galaxies span a huge range of distances from us, and the light from some of them has been travelling for billions of years to reach this telescope. This means that here, we aren't just looking out across space, but also back in time, and seeing these galaxies as they were billions of years ago, much earlier in their lives. Hence the name, Legacy Survey of Space and Time. The Cosmos field is a particularly good place to do this. Astronomers have been looking at and studying this particular patch of sky for decades. It's been observed by Hubble, Euclid and other telescopes working across the electromagnetic spectrum, from radio waves to x-rays. The reason this patch is so popular is that it is away from the plane of the Milky Way that we mentioned earlier. It's obscured by relatively few foreground stars and less dust, so we can look through this clearer window and see huge numbers of distant galaxies. This image in particular was made by stacking hundreds of individual Rubin observations to get even more clarity and better resolution, and it contains an astonishing amount of information. Once again though, the most exciting thing is what we'll see and what will happen when we image the field repeatedly, night after night, and we get a movie of how this patch of space changes. One of those 650,000 galaxies might suddenly contain a supernova. Something that was invisible in the first image might suddenly become bright. An active galaxy might flare. By comparing new observations with old ones, Rubin can find those changes. That's kind of the key difference between a traditional, conventional astronomical survey and the new Rubin Observatory. We're not just making a map here. It's a map along with a timeline, a movie. The images we've looked at today were taken before Rubin's main survey began. But now, the real thing is underway. There have been a few delays due to weather at the observatory causing a lot of damage in the local area. But soon, that movie is going to be recording, and I can't wait to see it. Ruben is now taking about 700 images of the southern sky every night. And over the next 10 years, it will continue doing this, building a cinematic record of the changing universe. This really does feel like the next step in our ability to map stars, galaxies, and the universe. A galaxy won't just be a dot on a map, a star won't just be a point of light. Every object now becomes part of this evolving story. Something that brightens, something that moves, and something that might explode. Some things will appear and some will disappear. The greatest cosmic movie ever made has finally begun filming. I'll leave links in the description below if you want to check out these images at full resolution. And if you have any questions about any of those pictures or Rubin itself, please feel free to leave them down below. If you're as excited as I am about the next decade and beyond of astronomy, please consider subscribing so we can explore all of these new discoveries together. And thanks a lot for watching. Until next time, stay safe team. I'll see you soon. Bye! This guy's causing chaos while I film. He's knocking things off the table. He's mad. You wanna see some pictures?