This Amazing Mission Almost Failed After Launch

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The ESA Hipparcos team worked for 20 years on the project, then had to watch as the mission ALMOST failed! But somehow, they turned it around, and today, this little-known mission has totally transformed what we know about space.

Hosted by: Reid Rimers

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Sources:
https://sci.esa.int/web/hipparcos/-/47357-fact-sheet
https://sci.esa.int/web/hipparcos/-/31905-about-the-mission
https://www.cosmos.esa.int/web/hipparcos/scientific-goals
http://www.astronomy.com/news/2005/01/hipparchuss-sky-catalog-found
https://www.cosmos.esa.int/documents/532822/546213/vol2_all.pdf/39073ea4-8e7a-4b07-8094-6ce046f0e4db
https://wwwhip.obspm.fr/heritage/hipparcos/SandT/hip-SandT.html
https://www.spenvis.oma.be/help/background/soldam/soldam.html
http://adsabs.harvard.edu/abs/1997A&A...323L..49P
https://doi.org/10.1051/0004-6361:20078357
http://adsabs.harvard.edu/abs/1997A&A...323L..57H
http://adsabs.harvard.edu/abs/2000A&A...355L..27H
https://arxiv.org/pdf/astro-ph/9707107.pdf
https://iopscience.iop.org/article/10.1086/305201
https://www.cosmos.esa.int/documents/532822/553347/feast_ceph.pdf/9cf31b5f-dc80-454c-b547-338dc973fc59
Planck: https://arxiv.org/abs/1807.06209
SL9: https://www.cambridge.org/core/services/aop-cambridge-core/content/view/7C7A50945B166FCC28D197F3A53EB2D5/S025292110011543Xa.pdf/orbital_motion_and_impact_circumstances_of_comet_shoemakerlevy_9.pdf
https://nssdc.gsfc.nasa.gov/planetary/impact.html
Other discoveries: https://iopscience.iop.org/article/10.1086/300364
https://www.cosmos.esa.int/web/hipparcos/poster
https://arxiv.org/abs/astro-ph/9707253
https://www.cosmos.esa.int/documents/532822/553347/aa_letter.pdf/93714a5a-c3d2-4a1f-8a9d-53ecbb909f52

Image Sources:
https://commons.wikimedia.org/wiki/File:Hipparcos-testing-estec.jpg
https://commons.wikimedia.org/wiki/File:The_Blue_Marble_4463x4163.jpg
https://commons.wikimedia.org/wiki/File:Observatory_in_Alexandria_at_the_Time_of_Hipparchus.jpg
https://svs.gsfc.nasa.gov/3951
https://en.wikipedia.org/wiki/File:The_globular_cluster_NGC_6388,_observed_by_Hubble.jpg
https://apod.nasa.gov/apod/ap130909.html
https://svs.gsfc.nasa.gov/12900
https://www.istockphoto.com/photo/cloud-typologies-night-sky-milky-way-gm879837540-245198742
https://www.flickr.com/photos/gsfc/8517114274
https://www.videoblocks.com/video/fly-through-outer-space-nebula-and-stars-animated-background-b5c6fktyeizjo797m
https://solarsystem.nasa.gov/resources/2471/comet-shoemaker-levy-9-jupiter-impact-visualization/