We're back, baby! And we're seeing double! Ring in the new-ish year with us as we reflect on mirrors!

Deboki is hosting a new podcast called Tiny Matters! It’s a science podcast about “the little stuff that makes the big stuff possible!” You can subscribe here! And be sure to follow her on Twitter: @okidoki_boki

Head to https://www.patreon.com/SciShowTangents to find out how you can help support SciShow Tangents, and see all the cool perks you’ll get in return, like bonus episodes and a monthly newsletter!

And go to https://store.dftba.com/collections/scishow-tangents to buy your very own, genuine SciShow Tangents sticker!

A big thank you to Patreon subscriber Garth Riley for helping to make the show possible!

Follow us on Twitter @SciShowTangents, where we’ll tweet out topics for upcoming episodes and you can ask the science couch questions! 

While you're at it, check out the Tangents crew on Twitter: Ceri: @ceriley Sam: @im_sam_schultz Hank: @hankgreen

[The Scientific Definition]

Heliograph

https://www.theatlantic.com/photo/2014/04/world-war-i-in-photos-technology/507305/

https://www.nps.gov/fobo/learn/historyculture/the-heliograph.htm

https://books.google.com/books?id=RBC2nY1rp5MC&q=heliograph&pg=PA211#v=snippet&q=heliograph&f=false

Pseudoscope 

http://waywiser.fas.harvard.edu/objects/3538/combination-stereoscope-telestereoscope-and-pseudoscope;jsessionid=ADBDCEF0ECA144094F58FDB5779EB61B

https://digitalcommons.bucknell.edu/cinematic/3/

https://books.google.com/books?id=0_QMAAAAIAAJ&pg=PA146&dq=pseudoscope&as_brr=1#v=onepage&q=pseudoscope&f=false

Etalon  

http://hyperphysics.phy-astr.gsu.edu/hbase/phyopt/fabry.html

https://www.sciencedirect.com/topics/physics-and-astronomy/etalons

https://www.osapublishing.org/ao/abstract.cfm?uri=ao-5-6-985

Reflecting circle

https://amhistory.si.edu/navigation/type.cfm?typeid=5

https://royalsocietypublishing.org/doi/10.1098/rstl.1801.0019

Pictures: https://en.wikipedia.org/wiki/Reflecting_instrument#Reflecting_circles

[Trivia Question]

James Webb Space Telescope mirrors

https://webb.nasa.gov/content/observatory/ote/mirrors/index.html

https://spaceplace.nasa.gov/telescopes/en/

[Fact Off]

Enantiomers (mirror versions of chemical compounds)

https://spinoff.nasa.gov/Spinoff2004/ch_4.html

https://www.smithsonianmag.com/space/must-all-molecules-life-be-left-handed-or-right-handed-180959956/

https://www.diabetes.co.uk/blog/2015/06/the-version-of-sugar-that-wont-affect-your-blood-glucose-levels-and-why-you-cant-have-it/

https://www.wired.com/2003/11/newsugar/

The Venus Effect (mirror sight-lines) 

https://www.bertamini.org/lab/venus.html

https://www.semanticscholar.org/paper/The-Venus-effect-in-real-life-and-in-photographs-Bertamini-Lawson/c6d67537323365e8fdae3c7e1b02635c7b1901aa/figure/3

[Ask the Science Couch]

Super efficient mirrors 

https://www.scientificamerican.com/article/what-is-the-physical-proc/

https://news.mit.edu/1998/mirror

http://www.cnn.com/2008/HEALTH/12/19/laser.surgery/index.html

https://physicsworld.com/a/crystalline-supermirrors-cut-optical-losses/

https://www.thorlabs.com/newgrouppage9.cfm?objectgroup_id=14069

[Butt One More Thing]

Mirror test IBS

https://pubmed.ncbi.nlm.nih.gov/3617051/

https://pubmed.ncbi.nlm.nih.gov/16258235/