planet Facts | Britannica

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link-gray-900" href="/science/planet#ref256234">Planets of other stars</a></div><div class="ml-40 toc-drawer sub-toc-drawer"></div></li></ul> <a class="toc-extra-link link-gray-900" href="https://www.britannica.com/science/planet/additional-info">References & Edit History</a> <a class="toc-extra-link link-gray-900 selected" href="/facts/planet">Related Topics</a> </div> <div class="tlr-media-slider pb-10 mb-30"> <a class="section-header link-gray-900 font-serif font-14 font-weight-bold mb-10 mx-10" href="https://www.britannica.com/science/planet/images-videos">Images & Videos</a> <div class="slider js-slider position-relative d-inline-flex align-items-center mw-100 "> <div class="slider-container js-slider-container overflow-hidden d-flex overflow-hidden text-nowrap ml-15"> <a href="https://cdn.britannica.com/01/81401-050-8EB87030/planets-solar-system-Pluto-montage-images-Sun.jpg" data-href="/media/1/463008/74702" class="media-overlay-link d-inline-block mr-5"> <img loading="lazy" 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text-hyphenate" href="/biography/Isaac-Newton">Isaac Newton</a> <div class="caption mt-5 text-hyphenate">English physicist and mathematician</div> </div> </div> </div> <div class="col-50 col-md-33 col-lg-20"> <div class="card card-sm"> <div class="card-media" style="--aspect-ratio: 3/4"> <img loading="lazy" src="https://cdn.britannica.com/04/1904-004-D1A961F7/Johannes-Kepler-oil-painting-artist-Strasbourg-cathedral.jpg?h=400&w=300&c=crop" alt="Johannes Kepler" /> </div> <div class="card-body"> <a class="font-weight-bold text-hyphenate" href="/biography/Johannes-Kepler">Johannes Kepler</a> <div class="caption mt-5 text-hyphenate">German astronomer</div> </div> </div> </div> <div class="col-50 col-md-33 col-lg-20"> <div class="card card-sm"> <div class="card-media" style="--aspect-ratio: 3/4"> <img loading="lazy" src="https://cdn.britannica.com/29/18829-050-3F57E4F8/Galileo-Justus-Sustermans-Uffizi-Gallery-Florence-1637.jpg?h=400&w=300&c=crop" alt="Galileo" /> </div> <div class="card-body"> <a class="font-weight-bold text-hyphenate" href="/biography/Galileo-Galilei">Galileo</a> <div class="caption mt-5 text-hyphenate">Italian philosopher, astronomer and mathematician</div> </div> </div> </div> <div class="col-50 col-md-33 col-lg-20"> <div class="card card-sm"> <div class="card-media" style="--aspect-ratio: 3/4"> <img loading="lazy" src="https://cdn.britannica.com/mendel-resources/3-133/images/shared/default3.png?v=3.133.36" class="default " /> </div> <div class="card-body"> <a class="font-weight-bold text-hyphenate" href="/biography/Didier-Queloz">Didier Queloz</a> <div class="caption mt-5 text-hyphenate">Swiss astronomer</div> </div> </div> </div> <div class="col-50 col-md-33 col-lg-20"> <div class="card card-sm"> <div class="card-media" style="--aspect-ratio: 3/4"> <img loading="lazy" src="https://cdn.britannica.com/mendel-resources/3-133/images/shared/default3.png?v=3.133.36" class="default " /> </div> <div class="card-body"> <a class="font-weight-bold text-hyphenate" href="/biography/Michel-Mayor">Michel Mayor</a> <div class="caption mt-5 text-hyphenate">Swiss astronomer</div> </div> </div> </div> <div class="col-50 col-md-33 col-lg-20"> <div class="card card-sm"> <div class="card-media" style="--aspect-ratio: 3/4"> <img loading="lazy" src="https://cdn.britannica.com/mendel-resources/3-133/images/shared/default3.png?v=3.133.36" class="default " /> </div> <div class="card-body"> <a class="font-weight-bold text-hyphenate" href="/biography/Eudoxus-of-Cnidus">Eudoxus of Cnidus</a> <div class="caption mt-5 text-hyphenate">Greek mathematician and astronomer</div> </div> </div> </div> <div class="col-50 col-md-33 col-lg-20"> <div class="card card-sm"> <div class="card-media" style="--aspect-ratio: 3/4"> <img loading="lazy" src="https://cdn.britannica.com/mendel-resources/3-133/images/shared/default3.png?v=3.133.36" class="default " /> </div> <div class="card-body"> <a class="font-weight-bold text-hyphenate" 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style="--aspect-ratio: 3/4"> <img loading="lazy" src="https://cdn.britannica.com/mendel-resources/3-133/images/shared/default3.png?v=3.133.36" class="default " /> </div> <div class="card-body"> <a class="font-weight-bold text-hyphenate" href="/biography/George-William-Hill">George William Hill</a> <div class="caption mt-5 text-hyphenate">American astronomer</div> </div> </div> </div> <div class="col-50 col-md-33 col-lg-20"> <div class="card card-sm"> <div class="card-media" style="--aspect-ratio: 3/4"> <img loading="lazy" src="https://cdn.britannica.com/mendel-resources/3-133/images/shared/default3.png?v=3.133.36" class="default " /> </div> <div class="card-body"> <a class="font-weight-bold text-hyphenate" href="/biography/William-Rutter-Dawes">William Rutter Dawes</a> <div class="caption mt-5 text-hyphenate">British astronomer</div> </div> </div> </div> <div class="col-50 col-md-33 col-lg-20"> <div class="card card-sm"> <div class="card-media" style="--aspect-ratio: 3/4"> <img 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