WEBVTT 00:24.380 --> 00:29.020 Welcome back to another episode of Competition Update, Space Security Challenge style. 00:29.020 --> 00:30.860 I'm your host, Jordan Wines. 00:31.080 --> 00:38.620 Several teams are showing indications that they're making progress on the hardest challenge, number four, but we don't have any confirmed solutions yet. 00:38.620 --> 00:43.660 Be aware, though, that at some point in the next few hours, the scoreboard might be going off. 00:43.740 --> 00:56.320 Depending on the organizers, anyway, many in-person CTFs have a tradition of blanking the scoreboard toward the end for a little bit of increased drama, and I'm told we might see that happen here so teams could slip in a surprise solution when that happens. 00:56.400 --> 01:02.000 With no point decay, you probably have no incentive to hold back on an answer that you might otherwise do in a normal CTF. 01:02.160 --> 01:09.380 If you've been watching this carousel webcams, you might have noticed the occasional astronaut heading into space around our flatsats. 01:09.640 --> 01:11.040 Let's go ahead and take a look now. 01:11.040 --> 01:12.100 Oh, we've got some audio. 01:12.160 --> 01:13.520 Let's see if we can mute that. 01:17.300 --> 01:18.820 I'm not sure if it's coming through on that. 01:18.820 --> 01:23.780 Yeah, unfortunately, we've got a little bit too much audio on that video, so we're going to have to probably kill that one. 01:23.780 --> 01:27.920 The video that you're not seeing actually has some of the CubeSats in slow motion. 01:27.920 --> 01:41.940 If you've been watching the webcams, we've actually got different views showing each of the satellites, the flatsats, as they're spinning around, orienting themselves on top of the sun. 01:41.940 --> 01:47.960 If we can stop this video before we zoom, it's going to be really good, or else you're going to hear some really interesting background noise. 01:48.420 --> 01:50.720 One of our explorers was able to get that video. 01:51.080 --> 01:55.280 It showed 1550 trees flatsat as it actually orbited around the room. 01:55.280 --> 01:58.680 We'll make sure to get that up on the YouTube playlist afterwards so you can catch it. 01:58.680 --> 02:03.860 It was able to keep itself oriented on the sun as it went around the room, that, of course, being one of the previous challenges. 02:04.480 --> 02:12.300 All right, for more information on the other things that have been going on behind the scenes, we're going to see if we can bring Alex Taylor from Crimealance into the feed as well. 02:12.720 --> 02:14.460 Alex, can you hear me, first of all? 02:14.940 --> 02:16.120 Yeah, I can hear you great. 02:16.120 --> 02:16.900 And I hear you, too. 02:16.900 --> 02:17.400 This is good. 02:17.400 --> 02:17.740 Awesome. 02:17.740 --> 02:19.560 All right, well, welcome to the stream. 02:19.560 --> 02:20.480 Thanks for coming on. 02:20.480 --> 02:21.020 Yeah , thank you. 02:21.560 --> 02:25.160 Okay, so first, can you tell me a little bit about what's been happening behind the scenes? 02:25.160 --> 02:30.880 I talked to Bright, I talked to the Jasons, and they kind of gave me some updates on some of the design things. 02:30.880 --> 02:35.840 But in terms of what's actually happening today and yesterday, anything interesting been going on? 02:36.380 --> 02:37.040 Sure. 02:37.040 --> 02:48.220 So all of the flatsats in the room are connected to the ground stations that the teams are on via radios. 02:48.380 --> 02:53.180 So one of the things that we have to do occasionally is move some of the radios around the room. 02:53.180 --> 03:00.020 Sometimes there is some interference either from other radios or, you know, just from things that get moved around in the room. 03:00.020 --> 03:02.700 Somebody starts to microwave a floor below or something, maybe? 03:05.020 --> 03:08.220 There's some bits of metal and stuff that might be in the way, too. 03:08.220 --> 03:20.640 So one of the things that you might see people come into frame doing is moving some of those radios around just to make sure that teams are not getting large amounts of packet loss when they're communicating with the satellites. 03:21.520 --> 03:26.420 Yeah, a little bit less deterministic than, I guess, a network challenge where the networks are a little bit more reliable. 03:26.420 --> 03:31.000 When you're working with RF for every connection you make, you've got to deal with a little bit of that. 03:31.000 --> 03:31.840 That makes sense. 03:31.840 --> 03:37.300 Yeah, and something we had to communicate to teams earlier as well is that this isn't a network service. 03:37.300 --> 03:40.620 So they have to be very careful with the amount of data that they're sending. 03:40.740 --> 03:47.060 They don't want to trip over themselves and cause their messages to not get completely sent. 03:47.140 --> 03:53.860 I saw that message going on in the team chat, and I like that because you kind of, as an organizer, you have to strike the balance between how much information you give. 03:53.860 --> 03:57.280 And, you know, you don't want to give a hint on something that may help one team more than others. 03:57.280 --> 04:00.340 But you want to also help everyone make productive progress. 04:00.340 --> 04:03.760 And you want people to be doing things that might hurt themselves. 04:03.880 --> 04:05.560 How else do you kind of have to deal with, like, fairness? 04:05.560 --> 04:09.280 Have any other kind of concerns that have come up throughout the game so far? 04:09.700 --> 04:10.200 Sure, yeah. 04:10.200 --> 04:24.120 So actually, early on day one, we realized that we had left a couple of files on certain teams' command and control systems from some earlier testing that we had done to make sure the challenges were solvable. 04:24.120 --> 04:35.060 Fortunately, the files that were left behind, we don't believe, gave away any information that would have been, you know, would have given teams an unfair advantage in the competition. 04:35.060 --> 04:53.080 But what we did is we decided to put all those files together into a single archive and give those out to all of the teams so that if we were wrong and those files contained something that was useful, at least every team had access to the same information before those challenges got released. 04:53.080 --> 04:54.040 Yeah, no, that makes sense. 04:54.040 --> 05:00.720 And I think that's, you know, you always have to, as an organizer, like, balance what decisions you make and trying to be fair is certainly important. 05:00.940 --> 05:04.360 One thing I'm asking everyone, what is your favorite challenge? 05:04.360 --> 05:11.340 And if it's not one we've seen yet, no spoilers, but if it's one we've already seen about, you can, of course, talk in detail, or even just which one you worked on that you thought was most interesting. 05:11.520 --> 05:12.000 Sure. 05:12.300 --> 05:13.780 Well, that's an interesting question. 05:13.780 --> 05:17.880 So you might expect me to say Challenge Zero, since that was the one that I worked on. 05:17.880 --> 05:18.160 I know you did that one. 05:18.160 --> 05:18.840 Yeah, yeah. 05:18.840 --> 05:19.700 Right. 05:20.000 --> 05:27.620 I would also say that Challenge Five, which is coming up, is pretty cool, because it's the culmination of everything that the teams have been doing. 05:27.760 --> 05:35.480 My personal favorite, though, is probably Challenge Three, just because it's the kind of challenge I would be interested in solving if I were playing this event. 05:35.480 --> 05:39.300 My background is very heavy on reverse engineering and exploitation. 05:39.580 --> 05:42.740 And that's exactly what you have to do to solve those challenges. 05:42.740 --> 05:46.580 Have a heavy amount of reverse engineering, you wind up with an exploit. 05:46.580 --> 05:47.520 It's good stuff. 05:47.520 --> 05:48.520 Yeah, I agree. 05:48.520 --> 05:50.180 That's why I highlighted that one as well. 05:50.180 --> 05:53.720 So, Alex, thank you very much for taking some time out from helping keep the game going. 05:53.720 --> 05:57.620 I'll let you get back to that, and we'll continue wrapping up this update. 05:58.040 --> 05:59.000 Thanks for having me. 06:00.760 --> 06:11.180 Finally, here's our last Space Talk episode of the event from Just Coffee, with a summary of how communications in space work, something our teams have surely demonstrated competence with over these past few days. 06:11.180 --> 06:17.080 Why do we use satellites like these for long-distance communication? 06:27.240 --> 06:35.940 Communicating with a satellite ranges from several buildings' worth of highly specialized equipment to a couple hundred dollars' worth of handheld amateur radio hardware. 06:36.000 --> 06:41.420 LEOSATs, only about 400 to 2,000 kilometers up, are even close by terrestrial standards. 06:41.420 --> 06:44.680 That means simple ham radios are often used to communicate with them. 06:44.680 --> 06:51.480 There's even one aboard the International Space Station that you can use to talk to the astronauts if you catch them at the right time and they're not too busy. 06:51.480 --> 06:55.680 The complexity with communicating with LEO satellites is actually their orbital speed. 06:55.740 --> 07:01.980 LEOSATs are moving so quickly that we have to use antennas that track them as they move rapidly across the sky. 07:01.980 --> 07:09.000 This tracking can be really difficult due to the uncertainty of the satellite location and how fast they move in and out of view. 07:09.040 --> 07:13.420 A satellite coming in and out of view from horizon to horizon is called a pass. 07:13.420 --> 07:16.960 Passes are the only times that we can actually communicate with satellites. 07:16.960 --> 07:24.260 Management of LEO satellites especially revolves entirely around these concept of passes and maximizing their effectiveness. 07:24.260 --> 07:33.640 For instance, it doesn't help having an imaging satellite over the target location if you didn't have a pass before it got to that location to tell it to take that photo. 07:33.640 --> 07:39.300 Similarly, you have to wait until the next pass to be able to actually bring that data back down to ground. 07:39.300 --> 07:43.640 Passes are roughly about 5 to 10 minutes for LEO satellites. 07:43.640 --> 07:47.580 This duration changes drastically based on where the ground station is located. 07:47.580 --> 07:54.020 Near the equator, the Earth's rotation actually causes the ground station and the satellite to lose contact with each other faster. 07:54.020 --> 08:00.780 But near the poles, Earth's rotation is negligible and the satellite is actually in view for almost twice as long, if not more. 08:00.780 --> 08:06.300 Essentially, the higher the latitude of your ground station, the more useful your passes actually end up being. 08:06.300 --> 08:12.240 This is the reason most ground stations are located in the higher latitudes, even in the very hard to reach locations. 08:12.240 --> 08:18.460 One of the best examples of that is Svalbard, a Norwegian archipelago that's extremely close to the North Pole. 08:18.460 --> 08:25.060 It has over 100 commercial ground station antennas, making it the largest commercial ground station in the world. 08:34.430 --> 08:42.390 As always, thanks Jess for the content and thanks to the team at the different studios for that awesome editing and animations that go into those Space Talk episodes. 08:42.570 --> 08:45.250 That's our last hourly update of the competition. 08:45.250 --> 08:57.230 I look forward to seeing everyone at 4pm Pacific, 7pm Eastern, as we will have our final daily recap where we will reveal which team's solution is being run on our satellite.