Listen: Andrew Dunkley, Fred Watson, Hippo Camp discussed on Space Nuts
"In fifteen seconds guidance internal Chan nine ignition sequence, Spence Spence nuts. nuts. Three four five eighty one. At the not reported feels good. Once again. Thank you for joining us on yet. Another addition of space nuts. My name is Andrew Dunkley and Fred Watson as always joins me to talk strana me. Hello, fade. Andrew seems like no time tools into one hundred fifty five funny that. Now. Jokes tonight. We're going to be talking about a mini moon, many muni rant Neptune. In fact, we're also going to look at that issue of heavy water, which stems from an episode we did a couple of weeks ago regarding how earth's oceans may have come into being perhaps water deposited by asteroids. But we learnt during that particular discussion that is more than one kind of water out there. And it was possible that heavy-water my have ended up on earth, instead of standard water and prompted a question in my mind as to what planet might be like, if it was covered in heavy-water, and whether or not we would survive in such an environment. So we'll look into that, and we'll answer some questions about whether or not wormholes exist in could we travel through them and a question about the dock meta highlights and the effect on time, great questions coming up soon. But I the. Many moon of Neptune. Interesting. Yeah. It's a it's a story that. Saw origins in, you know. Basically strenuous surveying. The outer solar system. In fact, it was it was a Hubble telescope image that I elected scientists actually based in the United States to the possibility that there's another moon of Neptune. Now I've lost count of moons. Neptune has when I was a kid had four think something on a very small number. But now it's more because of course back in the nineteen seventies, the void space craft I think is was to two flew by Neptune. And send back images of that will, that's the only time Neptune has been visited we the two outer planets Renison that tune the, the least well-studied Divulje bodies in the solicits mold illogic bodies in the solar system by anyway, -cially it has fourteen. Thank you, that you are naval. So he's grown a bit since since my time, but it's got a another one an it's a tiny object. I mean you know. Given how far away Neptune is. It's distances measured a billions of kilometers, it's something like for five billion kilometers gotten the exact number from are from the song. But this object is about thirty kilometers across. It's not bad going to detect it. That means it's very faint. And it was as I said, it was on the Hubble telescope image that it was, I noticed, but then what you've got to do is conferment on face dot confirmation has taken quite a long time. Because unique to observe something like that. A very Catholic festival too to ensure it's really that Secondly to try to do what so his like so how'd you find if it's really that, when it's, it's only just tickling the, you know, the electrons on your detector, when you take an image of it. So what you do is you, you take repeated images. This is a common technique in astronomy while he tried to observe very Thang things you take multiple images of it, and stack them one on top of the other. So you are the you add together digitally, the, you know, the pixel values for each image, and that will bring out anything that he's very faint. It'll tend to enhance the contrast, especially if you do it in, in clever ways. But the problem is, if you do that with something that's moving through space than just stacking a whole pile of images is gonna give you. It's not going to gain you anything because h image new image of the object. Will fall in a different place because it's moving. So what you have to do is take a guess as to what is motion is. And then shift, the images when you add them so that you stacking in a kind of motion compensated way, this is a bit technical. But what it does is it results in a much greater sensitivity, that is exactly how this little world has been discovered. They, they took something like eight five minute exposures, and then shifted them so that they didn't smear out the over the motion of this little moon, and is that, that they've got it and it's now been fully named by the international astronomical union in, in the Neptune system. The moons are conventionally nine after sacred Shire's as you'd expect because Neptune's the God of the sea and God's from from Greek and Roman mythology. And so this one is. Called hippo camp. It's actually the name of that monster. You might have seen a kind of host like fish like monster. That often pulls net tunes chariot in depictions of the way these gods go around the heavens. If you look at things like that, not, not a creature is called hippocampal not. He's now the name of this of this move. Yeah. I'm just looking through them. Now this some fabulous night's. Triton. Proteus dispeat-, Galilea, hippocampus, actually, in that fourteen that I found so already or or loaded, yet it's actually hippocampus obits, just inside the protests. Protests is a much bigger object is ten times, the size of hippocampus something like you know, three fifty kilometers across. With some interesting aspects is how she go. Big crater only the. Must must have been caused by any patents on some telling and some, some of these moons aren't really all that, spherical, either. I know undone hippocampal will be either. It's too small to be very cool, and I understand it's also very fast object in comparison to the orbit of Al moon. Yes, that's right. So it speed is about ten kilometers per second in orbit, that's actually, in ups, loot dubs. It's not that fast to when any spacecraft goes into it was around the earth is traveling usually about eight kilometers per second. But now moon obits at one kilometer per second. So it's much faster than the speed development. And of course, the way over dynamics work the closer, you get to your parents melody in the bigger your parent body is the faster you have to. And that's why he camp is orbiting very quickly around the planet Neptune. Mci and there's probably mortar discover at the because. Yeah. We, we finding stuff all the time, and these, these guests Gionta, Vaz's keep throwing up all these auditees in new discoveries. It's. Even in our own backyard, despite the fact that we go technology that can take us into vast vastly distant parts of the universe. We still find amazing things in our own backyard, which I think, is just fabulous. Yeah. Indeed. Okay. You're listening to space nuts, Andrew Dunkley here with Fred Watson. Okay. We checked systems. Now."