Santiago Andrés Triana<p>Flood <a href="https://fediscience.org/tags/tide" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#<span>tide</span></a>. This is a <a href="https://fediscience.org/tags/timelapse" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#<span>timelapse</span></a> of the Belgian coast compressing 5 hrs into 16 secs. Tides are caused mainly by the Moon's gravitational pull, and the energy dissipated by the tidal flow is taken from the Moon's orbital motion, making it go a bit slower, hence a bit further away every day.</p><p>As the <a href="https://fediscience.org/tags/Moon" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#<span>Moon</span></a> moves to a higher orbit its <a href="https://fediscience.org/tags/AngularMomentum" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#<span>AngularMomentum</span></a> actually increases. Therefore the Earth's angular momentum needs to decrease to keep the total Earth+Moon conserved. When the Moon formed a day was probably shorter than 10 hours.</p><p><a href="https://fediscience.org/tags/physics" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#<span>physics</span></a> <a href="https://fediscience.org/tags/science" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#<span>science</span></a> <a href="https://fediscience.org/tags/PlanetaryScience" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#<span>PlanetaryScience</span></a></p>