The Cosmic Ladder That Lets Us Map the Universe

Considering how massive our universe is, we know the distances to cosmic objects surprisingly well. What tools and clues do scientists use to measure distances that are so enormous they sound like made-up numbers?

Hosted by: Reid Reimers

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Sources:
https://books.google.com/books?id=0H0fjBeseVEC&pg=PA34#v=onepage&q&f=false
https://link.springer.com/article/10.1007/BF00329826
http://spiff.rit.edu/richmond/asras/measure_ss/measure_ss.html
https://astro.unl.edu/naap/distance/distance.html
http://adsabs.harvard.edu/full/1962AJ.....67..181P
https://www.lpi.usra.edu/lunar/missions/apollo/apollo_11/experiments/lrr/
https://phys.org/news/2015-01-distance-sun.html
https://phys.org/news/2014-05-distance-moon.html
https://blogs.esa.int/venustransit/2012/05/30/measuring-the-size-of-the-solar-system-parallax/
https://lco.global/spacebook/distance/parallax-and-distance-measurement/
https://lco.global/spacebook/light/redshift/
https://www.indiebound.org/book/9780375713453
https://usm.maine.edu/planet/how-did-astronomers-determine-cepheid-brightness-depends-their-periods-wouldnt-they-have-had
https://physicstoday.scitation.org/doi/full/10.1063/PT.3.1348
https://pdfs.semanticscholar.org/61f9/f419bbbb46424c1e215bae5cfc82452210b4.pdf [PDF]
https://www.noao.edu/staff/shoko/tf.html

Image Sources:
https://images-assets.nasa.gov/image/iss034e054858/iss034e054858~large.jpg
https://commons.wikimedia.org/wiki/File:Andromeda_Galaxy_(with_h-alpha).jpg
https://www.nasa.gov/multimedia/imagegallery/image_feature_1768.html
https://svs.gsfc.nasa.gov/10145
https://svs.gsfc.nasa.gov/13578
https://commons.wikimedia.org/wiki/File:M101_hires_STScI-PRC2006-10a.jpg