1 00:00:01,920 --> 00:00:06,320 Speaker 1: Welcome to brain Stuff production of I Heart Radio. Hi 2 00:00:06,400 --> 00:00:08,760 Speaker 1: brain Stuff. I'm Lauren vogel Bomb, and this is a 3 00:00:08,760 --> 00:00:12,159 Speaker 1: classic episode from our archives. In this one, we were 4 00:00:12,200 --> 00:00:15,600 Speaker 1: wondering how feasible it would actually be to outrun a 5 00:00:15,680 --> 00:00:19,040 Speaker 1: volcano the way that action heroes do in movies. So 6 00:00:19,160 --> 00:00:21,599 Speaker 1: we looked up some numbers and did some math. The 7 00:00:21,680 --> 00:00:27,720 Speaker 1: prognosis isn't great. Welcome to brain Stuff from How Stuff Works, 8 00:00:30,040 --> 00:00:33,159 Speaker 1: Hi brain Stuff, Lauren Vogel Bomb. Here it's a familiar 9 00:00:33,159 --> 00:00:37,240 Speaker 1: cinematic situation. A daring scientist arrives in town to study 10 00:00:37,280 --> 00:00:39,920 Speaker 1: the local volcano, which has been dormant for centuries but 11 00:00:39,960 --> 00:00:43,559 Speaker 1: now seems dangerously close to erupting. Despite the dire warnings 12 00:00:43,560 --> 00:00:46,640 Speaker 1: of everyone around him, the intrepid volcanologist, perhaps with a 13 00:00:46,680 --> 00:00:50,000 Speaker 1: trusty and attractive assistant in tow, insists on scaling the 14 00:00:50,000 --> 00:00:53,040 Speaker 1: mountain to more closely examine its condition. But just as 15 00:00:53,120 --> 00:00:56,040 Speaker 1: the pair arrives at the gaping crater, it blows, sending 16 00:00:56,080 --> 00:00:59,240 Speaker 1: them running or possibly jeeping, hand in hand down the 17 00:00:59,280 --> 00:01:02,600 Speaker 1: slope early staying ahead of the raging river of hot lava. 18 00:01:03,360 --> 00:01:06,000 Speaker 1: Seeing any number of these exhilarating scenes might leave you 19 00:01:06,040 --> 00:01:08,959 Speaker 1: wondering what would happen if I suddenly needed to escape 20 00:01:09,000 --> 00:01:11,560 Speaker 1: from an erupting volcano. Could I outrun the lava and 21 00:01:11,600 --> 00:01:16,039 Speaker 1: make it to safety? Well, technically yes. If lava were 22 00:01:16,080 --> 00:01:18,319 Speaker 1: all you had to deal with while scrambling down the 23 00:01:18,360 --> 00:01:21,080 Speaker 1: side of a fiery mountain, you might be in the clear. 24 00:01:21,800 --> 00:01:25,360 Speaker 1: Most lava flows, especially those from shield volcanoes the less 25 00:01:25,360 --> 00:01:28,840 Speaker 1: explosive type, are pretty sluggish. As long as the lava 26 00:01:28,880 --> 00:01:31,639 Speaker 1: doesn't find its way into a tube or shoot shaped valley, 27 00:01:31,680 --> 00:01:34,319 Speaker 1: it will probably move slower than a mile per hour. 28 00:01:34,840 --> 00:01:37,399 Speaker 1: For example, the lava flow from the Mauna Lower eruption 29 00:01:37,400 --> 00:01:39,920 Speaker 1: of nineteen fifty was clocked at six miles per hour. 30 00:01:40,160 --> 00:01:43,640 Speaker 1: That's nine kilometers per hour. You probably wouldn't have any 31 00:01:43,680 --> 00:01:46,800 Speaker 1: trouble scurrying away from that. There have been examples of 32 00:01:46,840 --> 00:01:49,200 Speaker 1: fast moving lava, but there are few and far between, 33 00:01:49,720 --> 00:01:53,080 Speaker 1: Like when the Democratic Republic of Congo's mountaineer Gongo erupted 34 00:01:53,080 --> 00:01:56,440 Speaker 1: in ninety seven, Its lava was measured going forty miles 35 00:01:56,440 --> 00:01:59,480 Speaker 1: per hour that's sixty four kilometers per hour, and at 36 00:01:59,520 --> 00:02:03,480 Speaker 1: least two thousand people lost their lives. The unfortunate truth, though, 37 00:02:03,520 --> 00:02:05,440 Speaker 1: is that lava will be the least of your worries 38 00:02:05,520 --> 00:02:07,840 Speaker 1: if you're close enough to an erupting volcano that you're 39 00:02:07,920 --> 00:02:11,200 Speaker 1: thinking about running for your life. Contrary to what we 40 00:02:11,280 --> 00:02:13,359 Speaker 1: might see in the movies, the dangers of a volcanic 41 00:02:13,480 --> 00:02:16,720 Speaker 1: eruption are not confined to burning hot lava. Even if 42 00:02:16,760 --> 00:02:19,320 Speaker 1: you could stay ahead of the lava, you'd never survived 43 00:02:19,360 --> 00:02:23,640 Speaker 1: the pyroclastic flow that's the accompanying, burning hot, fast moving 44 00:02:23,639 --> 00:02:28,040 Speaker 1: cloud of ash, rock, gas, and debris. Pyroclastic flows are 45 00:02:28,040 --> 00:02:30,799 Speaker 1: the worst when they come from the more dramatically explosive 46 00:02:30,880 --> 00:02:34,320 Speaker 1: composite volcanoes, but they generally move at speeds greater than 47 00:02:34,360 --> 00:02:37,079 Speaker 1: sixty miles per hour a k a ninety six kilometers 48 00:02:37,120 --> 00:02:40,400 Speaker 1: per hour and reach temperatures between about two hundred and 49 00:02:40,480 --> 00:02:45,280 Speaker 1: seven hundred degrees celsius that's around four hundred hundred degrees fahrenheit. 50 00:02:46,000 --> 00:02:49,000 Speaker 1: By many estimates, the pyroclastic flow from the infamous eruption 51 00:02:49,000 --> 00:02:52,119 Speaker 1: of Mount Vesuvius in seventy nine c E reached four 52 00:02:52,200 --> 00:02:55,320 Speaker 1: hundred and fifty miles per hour or seven hundred kilometers 53 00:02:55,320 --> 00:02:58,200 Speaker 1: per hour. There's obviously no way anyone's out running that. 54 00:02:58,760 --> 00:03:01,519 Speaker 1: And if the pyroclastic flow happens to melt snow or 55 00:03:01,560 --> 00:03:05,720 Speaker 1: a glacier. This creates a lahar and extra deadly concrete 56 00:03:05,760 --> 00:03:10,000 Speaker 1: thick mud slide slash avalanche combo. So, if you one 57 00:03:10,040 --> 00:03:12,240 Speaker 1: day find yourself flirting with danger on the rim of 58 00:03:12,240 --> 00:03:15,600 Speaker 1: an erupting volcano, we hate to say it, but your toast. 59 00:03:20,240 --> 00:03:22,640 Speaker 1: Today's episode was written by Alison Cooper and produced by 60 00:03:22,680 --> 00:03:25,440 Speaker 1: Tristan McNeil and Tyler clang Or. More on this and 61 00:03:25,520 --> 00:03:28,880 Speaker 1: lots of other explosive topics visit how stuff works dot com. 62 00:03:28,960 --> 00:03:31,800 Speaker 1: Brain Stuff is production of iHeart Radio. For more podcasts 63 00:03:31,880 --> 00:03:34,920 Speaker 1: my heart Radio, visit the iHeart Radio app, Apple Podcasts, 64 00:03:34,960 --> 00:03:36,800 Speaker 1: or wherever you listen to your favorite shows.