Daniel Fischer<p>30 years ago <a href="https://scicomm.xyz/tags/OTD" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>OTD</span></a> the International Astronomical Union Circular <a href="http://www.cbat.eps.harvard.edu/iauc/05800/05800.html" rel="nofollow noopener" target="_blank"><span class="invisible">http://www.</span><span class="ellipsis">cbat.eps.harvard.edu/iauc/0580</span><span class="invisible">0/05800.html</span></a> first predicted the impact of comet <a href="https://scicomm.xyz/tags/SL9" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>SL9</span></a> into <a href="https://scicomm.xyz/tags/Jupiter" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>Jupiter</span></a> a year later with the immortal words about the expected minimum distance from the center of the planet: "Delta_J will be only 0.0003 AU (Jupiter's radius being 0.0005 AU) on 1994 July 25.4."</p>