 Anyone who knows me knows my absolute favorite objects to photograph are emission nebulae. I just can't get enough of them. So while the Messier catalog is cool and all, it's not the catalog that I turn to the most often. As for my taste, it's just too full of star clusters and galaxies and galaxy clusters and things like that. My favorite catalog of all time is the Sharpless catalog named after American astronomer Stuart Sharpless, who cataloged 313 distinct H2 regions in the northern sky using glass plate photographs from the Palomar sky survey, and he did this in 1953. And that same survey you may know because it was digitized with other surveys to make the digitized sky survey of the whole night sky with red and blue plates. And there's some overlap between Sharpless, Messier, NGC, IC, all these different catalogs. But my favorite objects are often not in Messier or NGC, they're Sharpless objects. And the acronym for Sharpless objects you might see is SH2- and then the number. And the reason for the two in there is that it's the second release of the Sharpless catalog happened in 1958, and they updated some of the positions. Anyways, there's a great website out there called SharplessCatalog.com where amateur astronomer Dean Selman has photographed almost every object in the Sharpless catalog. And he gives great information about them, including their name, their constellation, their location, their shape, their size, brightness. He writes a nice paragraph about them. So there's all this kind of cool stuff in here. He also often includes a map. And what this map, what he means by map is mapped color. So he often shoots the HA, the O3, the S2, and you can sort of understand the relative signal of the different common neuroband filters and what they would look like also if you then map the monodata into a full color RGB image, you know, like a Hubble palette. And this is very handy. It's something that I get lots of questions about along the lines of, well, how do I know if it's worth shooting S2 for this object? And this is the kind of work that can tell you. I mean, if someone else has done it and you can look at what they've done. Now, before you get too excited, he's only done this for a few of the 313 objects that have the full map of all the narrowband channels, because he's mostly focused on just getting a color image of any kind. So getting just an RGB or sometimes an HA RGB image. But he also includes the inverse. He includes zooming in and out. So there's all kinds of cool stuff here. And so on ones where he doesn't have the map, like this one, if you want to know if you should shoot O3, you might just have to go out and do it yourself. But that's actually how some people have made cool discoveries. Because while we have HA surveys of basically the entire night sky, there I don't know if there's really an O3 survey of the whole night sky. So there's probably still cool stuff to find out there. And the closest corollary to the Sharpless Catalog that I can find for the Southern Hemisphere seems to be the Gum Catalog created by Colin Gum, an Australian astronomer. And it was published in 1955. So around the same time. And my favorite representation of the Gum Catalog on the net is Kevin Jardine's galaxymap.org site. He seems to have info on basically every gum object. And he's made full color photographs as well. These aren't ones that he's photographed himself, like Dean Selman did. Instead, these are from the Digitized Sky Survey, just a combination of the red and blue plates. So that's why they sort of come out pink like this. But great information, links to scientific papers, all kinds of stuff. And this whole site galaxymap.org is one that I go to and get very absorbed in because it's very rich. He's written this whole book, you know, about Milky Way cartography. And there's all kinds of like cool integrated tools within the book, like this Milky Way Explorer, that lets you sort of look at the plane of the galaxy, but with different surveys that have been done. And let's you zoom in and do all kinds of cool stuff. So I would definitely check out galaxymap.org and sharplesscatalog.com. These are two sites that I think I haven't heard many people talk about that I go to for inspiration all the time. Well, this has just been another hopefully short edition of Five Minute Friday. And we do this every week, just short videos that are released at 1030 a.m. Eastern every Friday. My name is Nico Carver. My website's nebulaphotos.com. Clear skies, everyone.