Filmmaker David Ruck and I have been collaborating with scientists, aerospace agencies, STEM institutions, space exploration non-profits, and among others, astronauts, in screening this film around the country toward a simple but profound goal:
“To tell the story of going…and remind everyone what NASA means to the world, reignite those dreams again, and explore space together.” — David Ruck (Director) and Rich Evans (Public Relations)
Volcanoes seem to be a common topic these days. Yesterday Nautilus published a great piece by Aatish Bhatia on the 1883 eruption of Krakatoa, which tore the island apart and unleashed a sound so loud it was heard more than 4800 km away:
The British ship Norham Castle was 40 miles from Krakatoa at the time of the explosion. The ship’s captain wrote in his log, “So violent are the explosions that the ear-drums of over half my crew have been shattered. My last thoughts are with my dear wife. I am convinced that the Day of Judgement has come.”
In general, sounds are caused not by the end of the world but by fluctuations in air pressure. A barometer at the Batavia gasworks (100 miles away from Krakatoa) registered the ensuing spike in pressure at over 2.5 inches of mercury1,2. That converts to over 172 decibels of sound pressure, an unimaginably loud noise. To put that in context, if you were operating a jackhammer you’d be subject to about 100 decibels. The human threshold for pain is near 130 decibels, and if you had the misfortune of standing next to a jet engine, you’d experience a 150 decibel sound. (A 10 decibel increase is perceived by people as sounding roughly twice as loud.) The Krakatoa explosion registered 172 decibels at 100 miles from the source. This is so astonishingly loud, that it’s inching up against the limits of what we mean by “sound.” #
Those are some mindbogglingly enormous numbers. Aatish does a wonderful job of explaining the science behind an explosion whose effects ricocheted through the atmosphere for days afterward. Check out the full article over at Nautilus. (Image credit: Parker & Coward, via Wikipedia)
I did a project of Krakatoa last year. The shock wave travelled around the Earth approximately seven times. The resulting ash thrust all of Europe (and probably the rest of the world) into a year without sun, causing crops to fail and famine to ensue. Some famous artwork has been attributed to the intense sunsets that could be seen all throughout Europe in the following years, like The Scream by Edvard Munch.