Uploaded January 2017 | Updated September 2026, 1 week ago

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The movie Alien's tagline was infamously "In space no one can hear you scream" - a great hook because as we all know there's no sound in space... except there is! Find out why sound is present in seemingly empty space, what exactly it is and how scientists listen to it.

W: martinarcher.co.uk
T: twitter.com/martinarcher
F: facebook.com/drmartinarcher

00:27 What is normal sound? Pressure waves, fluids & hydrodynamics
1:54 Space isn't a true vacuum - space plasmas
03:08 Sound in plasmas - MHD, magnetosonic and Alfven waves
05:14 Detecting sound in space
06:57 Why we care? Space weather

Links for more information

Sound
en.wikipedia.org/wiki/Acoustic_wave
en.wikipedia.org/wiki/Acoustic_wave_equation

Fluids
en.wikipedia.org/wiki/Fluid
www-mdp.eng.cam.ac.uk/web/library/enginfo/aerothermal_dvd_only/aero/fprops/propsoffluids/node2.html

Hydrodynamics
en.wikipedia.org/wiki/Fluid_dynamics
livescience.com/47446-fluid-dynamics.html

Space Plasma
ucl.ac.uk/mssl/space-plasma-physics/plasma-science
en.wikipedia.org/wiki/Space_physics

Magnetohydrodynamics
en.wikipedia.org/wiki/Magnetohydrodynamics
ucl.ac.uk/mssl/solar/summerschool13/lectures/MSSL-Arber.pdf

MHD Waves
en.wikipedia.org/wiki/Magnetosonic_wave
en.wikipedia.org/wiki/Alfv%C3%A9n_wave
http://farside.ph.utexas.edu/teaching/plasma/Plasmahtml/node65.html

Space Plasma Satellites/Missions
http://themis.ssl.berkeley.edu/
mms.gsfc.nasa.gov
http://sci.esa.int/cluster/
nasa.gov/content/goes
nesdis.noaa.gov/content/dscovr-deep-space-climate-observatory

Satellite Plasma and Field Instruments
en.wikipedia.org/wiki/Electrostatic_analyzer
en.wikipedia.org/wiki/Magnetometer#Fluxgate_magnetometer
nasa.gov/mission_pages/themis/spacecraft/EFI.html

Space Weather
en.wikipedia.org/wiki/Space_weather
metoffice.gov.uk/services/public-sector/emergencies/space-weather

SSFX is funded by a Queen Mary University of London Centre for Public Engagement Large Award
Music by Kevin Macleod and Audionatix