 Hey there fellow astronomers and night sky enthusiasts. Last night here in the Pacific Northwest, a bunch of people saw a string of lights in the sky. Understandably, when you walk outside and you see lights hovering in the sky slowly moving, it's very unsettling, a very unnatural feeling. Every time these kinds of things happen, people's imaginations race to absolutely incredible places. What we saw in the night sky was satellites. These were 60 or so Starlink satellites. This is the wireless internet company that Elon Musk and SpaceX is running that's in the news a lot. A group of these satellites had launched from Florida on a Falcon 9 rocket earlier that day, Star Wars Day, May the 4th, and they had gone around the Earth a few times, and so they were still in a very low orbit. It was nine o'clock, the sun was in the right place, the satellites were low, and what you were seeing was just reflected light. Now we call this line of satellites a Starlink train because it kind of looks like little cars on a choo-choo train moving through. People are reporting seeing these kinds of Starlink train events all over the world. But as a professional astronomer and someone who cares about like the environment, they're more than a little bit annoying. When we wanna study the edge of the universe, we need to be able to see it. And if there are bright things moving in front of us, we can't. This is actually a huge issue that a lot of people are concerned about here at UW, here in Seattle and elsewhere. People are going and getting data precious time on big telescopes only to get exposures completely wiped out and useless due to Starlink satellites passing in front of them. Now the satellites we saw last night were brand new, fresh out of the rocket. And they're gonna rise up over the next few weeks and get fainter. You won't be able to see them with your eyes. But we have telescopes that are the size of buildings and they can see them. SpaceX has been working with astronomers and with scientists to try to make the Starlink satellites a little fainter, a little darker. They've tried painting them and putting various covers on them. But the fact of the matter is you're gonna have tens of thousands of shiny things up in low Earth orbit and they're just gonna be in the way. This is a complicated issue because it involves technology and money and powerful people and it involves like environmentalism which doesn't always have the best PR apparently. Humanity has a long tradition of whenever we go into a new frontier or a new space we feel like we can just use it however we want. We've done this with the oceans and with animals and with land and with resources. As a species, we take a lot of things and consume them and use them. And we are not always mindful of our impact on our environment. Low Earth orbit is part of the Earth environment. Very much so. Throwing thousands of pounds of heavy metals and glass up in orbit and letting it come down and burn up and land on the planet. We're talking about this here because a month ago we saw a piece of this, a piece of a Falcon 9 burn up in the atmosphere. It was incredible and dramatic and beautiful even. Like fireworks are beautiful. And most of us said, including me, we don't expect much of this to hit the ground. It's not a big issue. Lo and behold, a couple of days later, people found a carbon fiber wrapped tank, something the size of a small table. I would not want that following on me. And look, you should not be actively concerned about space debris hitting you in the head. It's extremely unlikely. And most of the time NASA and spacefaring companies are able to get their debris to land where they want it in the ocean far away from people. But just basic statistics is gonna say that if we keep launching more and more of these things, if every week we're putting 60 more starlings up in orbit and every week more and more hardware is going in orbit, more stuff is gonna come down on us. I don't know what the balance is. I love outer space, both as an astronomer and just as a space nerd and space enthusiast. I love outer space. I love that we have people on the space station and that's an international cooperation. I got to go see a Falcon 9 launch, one of the very same SpaceX rockets that are taking starling satellites into orbit. I got to go see the test mission launch a couple years ago and it like brought literal tears to my eyes. It was an amazing and powerful experience to see something leave the earth. And I don't think we should go back to a time when we don't do those kinds of things. But what I know is that in the absence of any kind of mindfulness, of any kind of dare I say regulation about these issues, we're going to use and even abuse the resource that is low Earth orbit. We could put so much stuff up there that it becomes impossible for people to launch into space, space telescopes that taxpayers spend hundreds of millions or billions of dollars building get obliterated. And yes, more garbage will fall down and maybe somebody will get hurt. I don't know what the balance is. I don't know what the answer is. But I know we're only going to figure it out if we keep talking about it and if we keep looking up.