On November 9th near 8h Universal Time, minor planets Melpomene (magnitude 11.7), Hersilia (14.2), Marianna (14.8), Beagle (15.6), and Francette (15.7) have their minimum angular spread of 0.749°. But they actually satisfy the 1° criterion from November 3rd through 14th. As shown above, the five asteroids are moving toward the southeast at rates of 0.6" to 0.9" per minute. A set of CCD images spanning an hour or so, when stacked, should clearly show the five asteroids’ dotted trails.
The next quintuple grouping occurs on May 21, 2006, and involves Una, Fidelio, Andromacha, Tekmessa, and Libya. But the next after that, as defined above, does not take place until the year 2073.
By relaxing the conditions slightly, Vitagliano obtained a much longer list of asteroid get-togethers. When he took into account more than 2,000 asteroids that are believed to be larger than 20 km, he found 50 such groupings in the coming century, and one involves six asteroids. On June 15, 2024, Bondia, Ruth, Sirona, Lucia, Vanadis, and Eulalia will meet in a 1° patch in Gemini.
For this search Vitagliano used SOLEX (version 8.5), the remarkable computer program he has been developing since 1995. To learn more or to download this free program, visit his Web site.