2025 Asteroidal Occultations of Selected Categories - Updated 2025 July 28
August 2 occ'n by Uranus moon Umbriel over s.e. USA and cen. Mexico
August 10 occ'n of kappa Aquilae by 3km asteroid, s. Manitoba to n. Calif.; few other very bright N. American events during the rest of 2025
The text of our full asteroidal occultation section for the 2025 RASC Handbook is now posted here
Only a separate expanded page for Special Main Belt occultations is posted
Maps and Tables for all categories EXCEPT for the special MB events are given in a presentation .pdf and the Handbook text .pdf linked below; that's also the case for the 2025 Occult input files
These occultations are described and illustrated (in maps and tables) in this 2025 predictions presentation that is modified from one given at the 2024 IOTA meeting. The maps and tables for the bright main belt occultations are on slides 3 and 4 of the 2025 predictions presentation linked to above, and those for the other categories follow them in a similar form. Links to the .xml input files used by the Occult program, for main-belt and other categories of occultations (whose best events are also mapped and tabulated in the 2025 predictions presentation) are given below. A map and table of the better 2025 North American occultations by special main-belt (MB) asteroids are on slides 7 and 8 of the presentation; they are the ones portrayed on pages 248 and 249 of the Handbook. However, many more asteroids have been added in an update of that work, and new maps and tables created that you can find in this new Web page for them; read the .pdf document with link near the top of that page to see the maps and tables, and much information about all the new objects added, many being close binaries discovered during occultations, including several found since the Handbook information was generated last August. _____________________________ AUGUST 2 OCCULTATION OF 13.2-MAG. STAR BY UMBRIEL This Occult map from OWC shows the path over much of Mexico and the s.e. USA; that path is farther north with smaller errors than my Occult prediction from a year ago, so I think the current prediction may include the good astrometric point from the well- observed ocultation of 2020 Sep. 21. The Occult Watcher cloud page for the event has zoomable Aladin charts while this more detailed page has the zoomable Google map and more event details. I think an event ia possible as far north as cemtral AZ so we'll try it. I can not find the event on the Lucky Star prediction page. _____________________________ AUGUST 10 OCCULTATION OF KAPPA AQUILAE BY 3-KM ASTEROID AND OTHER BRIGHT ASTEROIDAL EVENTS IN N. AMERICA IN REST OF 2025 Occult maps for bright asteroidal occultations during the rest of 2025 are given below; the Aug. 10th event ties with Dec. 26 for the brightest asteroidal occultation in N. America for the rest of 2025. Aug. 10, 4.9mag kappa Aquilae, s. Manitoba to n. Calif. Aug. 23, 5.5mag ZC 3019 by Trebon, cen. Manitoba to n.w. Oregon Sep. 3, 5.6mag lambda Cap, s. N. Carolina to s. Baja Cal. Oct. 9, 5.1mag 89 Piscium, cen. Man. to n.w. Wash. and s. Vancouver Is. Dec. 26, 4.9mag SAO 110589 by Toni, Mexico to South Carolina Some other events only a little fainter than these are in the .pdf files covering all of 2025 linked to above, and on p. 245 of the RASC Handbook. _____________________________ Except for the special MB asteroids, we will not be posting pages for the other categories (bright MB events, NEAs, Trojans, and distant objects, as we've done for 2022, 2023, and 2024. It's too much work for us to prepare and update all those separate pages, so this year, we will not be doing that; we apologize that the published links to them won't work (so far, half way into 2025, I haven't received any complaints about them). If anyone else wants to prepare any of them, we will help teach them how. By eliminating them, we also remove the explanatory text they contained. Basic explanations of all categoris are given on pages 243-251 of the Handbook, so we provide in this .pdf document with the Handbook text, as we provided it in our last update on 2024 Sept. 1; a few minor editorial changes may have been made after that. It has the titles of the maps and tables to show where they should be, but you need to consult the 2025 presentation file with link above to see them. _ _ _ _ _ OCCULT INPUT FILES FOR 2025: Use of these files to generate your own predictions is described here. When you open these files with your Web browser, you should get a display that looks like this. The larger files may take a couple of minutes to show this appearance, showing a messed-up display before then. Once the proper view appears, right-click anywhere on the display, then "Save as" to a directory on your computer; the best directory is the \Asteroid\ subdirectory in your Occult\ directory. 16 North American brighter main belt events, in the Handbook and the 2025 presentatons file. thousands of North American main belt events to mag. 12.0 filtered to remove events with errors greater than 0.4 path widths Worldwide main belt events from Steve Preston to mag. 10.5 filtered to remove events with errors greater than 0.4 path widths - for them, prediction maps and data are available at https://www.asteroidoccultation.com/. Occultations by major planets and by their main satellites, and those combined with the above main belt files: Worldwide major planet/moon events North American subset of the above The above include cases with high RUWE and a few (mainly valuable irregular moons events) with relatively large path errors. Combined files (also posted on Robinson's site) Worldwide main belt events to mag. 10.5, and major planet/moon events North American main belt events to mag. 12.0, and major planet/moon events Occult Watcher is the best way to find out about upcoming events near your location; it includes the latest orbit updates from the JPL Horizons online system. You can learn about and obtain the software at this link. __________________________ INPUT FILES FOR OTHER CATEGORIES OF OCCULTATIONS Near-Earth asteroids (NEAs to mag. 13.0, since these are brief events usually needing mobile equipment): Currently, worldwide files for most of these events can only be found on Preston's Web site at https://www.asteroidoccultation.com/. Also, the selection for North America only considers the 20 most hazardous NEAs and a few others as described in the NEA section of the RASC 2025 text linked to above. North American 2025 selected NEA events, including Phaethon For the special NEA objects below, the files are for worldwide events: Occultations by Sisyphus and Tantalus 2005 UD has an elongated orbit with a small perihelion distance, requiring separate calculations for before and after perihelion; it is a probable flyby target of a Japanese asteroid mission: most 2025 occultations by 2005 UD late 2025 occultations by 2005 UD The rest of the files below have worldwide coverage to mag. 16: 2025 special Main Belt occultations but this has only about half of the objects that we have now. It is much better to get the new expanded files of special MB occultations covering the rest of 2025 from our new page of occultations by special MB asteoids for 2025. That also includes, near the bottom, an even larger number of Gaiamoon and Johnston binary asteroid events that, however, does not have many of the occultation asteroidal moon discoveries of the last 12 months or so that are included in our other files on the new page. 2025 Jupiter Trojan occultations, considering 43 Trojan asteroids, including objects larger than about 75 km and NASAs Lucy mission targets; their numbers are given in the RASC text .pdf linked to above. 2025 selected distant object occultations, considering 19 objects with their numbers given in the RASC text .pdf linked to above. __________________________ Pages for maps and predictions of occultations by the other special classes of asteroids are no longer given, as explained above; we apologize for the broken links published in the Handbook. Links to get the 2025 Occult input files for them are above. Below we give only the link to the new page for special MB occultations, also given below for completeness. Selected Special Main-Belt Asteroids ______ David and Joan Dunham, 2025 January 3; updated January 4 and July 28 e-mail: dunham@starpower.net cell phone: 301-526-5590