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Asteroid 1999XN37, aka (J99X37N), aka Doyan Rose
1999XN37 (Doyanrose) - was discovered December 7th 1999 from my observatory, which at the time consisted of a 10" LX200/ST-8 combo set up in my backyard. I was troubleshooting a tracking issue with the telescope and was doing periodic slews to the bright star (Zeta Persei) which is overexposed in the images. The asteroid is just to the right of the arrow.
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ASTEROIDS - WHY ARE THEY IMPORTANT?
1. One of these days, we (humanity) will be traveling through the asteroid belt (asteroids are largely found between the orbits of Mars and Jupiter although there are notable exceptions, see #4 below). When that time comes it'll be nice to know the orbit of each and every one of them, as well as their composition. They may be a source of material that could make the life of an interplanetary traveler easier (water, or some minerals that may be of use in rocket fuel).
While a chance collision between an asteroid and a spacecraft is unlikely, it would mean the loss of the spacecraft and whatever (or whomever) happened to be onboard.
2. Asteroids can give us an insight into the history of the solar system. All the large bodies (planets) have been altered over time. Asteroids are probably as close as we can get to examining remnants of the early solar system.
3. Life on Earth began somehow. Did an asteroid impact deliver the necessary organics to begin the process?
4. They do, on occasion (like October 7th, 2008) hit the earth. See: http://neo.jpl.nasa.gov/news/news159.html
5. Of all the trouble that Mother Nature can cause us, an asteroid impact is probably the only naturally occurring event than can seriously setback life on earth, and which is also avoidable given enough advanced warning.
The discoverer of a minor planet has the privilege of naming the body (more accurately, the discoverer has the privilege of proposing a name). I chose to honor my mother by suggesting her first and middle names, thus 'Doyan Rose'. She died in 1974 while I was in high school. Her and my father were always very supportive of my astronomical endeavors...letting one of your kids stay up half the night for years on end must have required considerable patience and understanding on their part. If I ever discover another, I'll probably want to name it after my father. That will be a bit tricky since we both have the same name, and minor planets are not supposed to be named after the discoverer. I'll worry about that when the time comes.
The 'Discovery Circumstances' portion of the JPL Small-Body Database Browser entry for Doyanrose. The JPL website is at: http://ssd.jpl.nasa.gov/sbdb.cgi#top
Minor Planet lightcurve work
174 Phaedra
I've lately began work on minor planet lightcurves. Minor planet lightcurve work is an attempt to learn more about the physical characteristics of minor plantes by observing and analyzing their change in brightness over time. My first effort along these lines were concentrated on Minor Planet 174 Phaedra.
A BRIEF ASIDE: Minor Planet 174 Phaedra was discovered September 2nd, 1877, by J.C. Watson at Ann Arbor, Michigan. Phaedra is a character from Greek mythology who, judging from the painting by Alexandre Cabanel (cleverly titled Phaedra, reproduced left), does not appear to have been having a good mythological existence. A friend suggested she appeared to have too much wine...given her role in mythology, it's easy to see why she would.
It is usually the prerogative of the discover to name a minor planet, but I've not yet come across any citation that Watson chose the name.
BACK TO REALITY - I collected roughly 600 images over five nights in November 2008 (the 4th, 18th, 19th 22nd and 28th UT) using a 12" f/10 SCT with a focal reducer, making the effective focal length about 73" (f/6). The camera was an SBIG ST-9 operating unbinned, resulting in an image scale of 2.2 arc-seconds/pixel, and all observations were 60 seconds long, unfiltered. When a suitable guide star was available, a SBIG AO-8 adaptive optics unit was utilized. The images were acquired and reduced with master flat field, dark and bias frames using CCDSoft. All images were then ran through CCD INSPECTOR, and those that had an aspect ratio of more than 50% (a result of image training due to either periodic error in the mount or wind pushing the telescope) were rejected (458 images were saved and used). Photometry and lightcurve analysis was down with CANOPUS.
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RESULTS: Marrying up this data with that of P.V. Sada (Universidad de Monterrey) and W. Cooney (Blackberry Observatory) it's in good agreement that 174 Phaedra has a rotation period of 5.75 hours.
I've passed these results along to Brian Warner (Palmer Divide Observatory). He'll be modeling results of what Phaedra actually looks like and publishing the results in THE MINOR PLANET OBSERVER. I'll post that here as soon as it's available.
Discovered November 15, 1892 by the prolific Max Wolf (University of Heidelberg, pictured left). Wolf pioneered the use of the astrographic techniques (i.e., taking pictures) to automate the discovery of asteroids. He named his first discovery Brucia, after the American philanthropist Catherine Bruce who gave Wolf $10,000 to build the telescope (known as the Bruce Double-Astrograph, photo by Rivi) with which he made many discoveries. I can't find a photo of Ms. Bruce that's in the public domain, otherwise she would be here too.
(343) Ostara was named after the early Norse goddess of Spring. The Easter rabbit was the escort of Ostara who contributed to the name Easter. In German it's "Ostern".
A lengthy spell of bad weather prevented acquiring more than two sessions (2.7 and 3.1 hour sessions respectively). Only descending branches of the lightcurve were observed. If the lightcurve is bimodal, it seems likely that the period would be considerably longer than the 6.42 h published by Binzel (1987). Dr. George Stecher (University of Wisconsin, private communication), who was also observing this object at about the same time, independently reached this same conclusion. The plot below 'forces' the date to a period of 13 hours, but that is only one of many possible solutions. Ostara won't be favorably placed for observations again until spring of 2010.
129 Antigone
ANTIGONE is the daughter of the mythological incestuous relationship between King Oedipus and Jocasta. There is also another Antigone (the daughter of Eurytion), but the discoverer of 129 Antigone states in the name citation that it is the "daughter of Oedipus" that he is referring to. The name citation mentions that "she guided her father when he was blind and exiled by her uncle Creon".
129 Antigone was discovered February 5th, 1873 by C.H.F. Peters of the Litchfield Observatory at Hamilton College in Clinton, New York. Peters discovered 48 asteroids in his career, all of them visually (astrophotography was in its infancy then).
Five nights of observations in January of 2009 are presented in the lightcurve below. My results show a synodic period of 4.9567 hours, while the published literature gives 4.9572...very close agreement.
232 Russia - (completed 5 March 2009)
Named, according to the citation, after "the former empire in eastern Europe and northern Asia which is nearly coextensive with the present U.S.S.R." Of course the current Russia is the old U.S.S.R. minus many of its former 'republics'.
John Palisa, the most successful visual discoverer of asteroids, found 232 Russia on January 31st, 1883. Palisa was an Austrian astronomer whose first gigs were as assistant at the University of Vienna Observatory, then as director of the Austrian Naval Observatory in Pola in 1872. At the ANO, he discovered 28 minor planets with a 6" refractor. Being a man who truly loved what he did, he resigned his directorship at ANO and made a move to a subordinate position at the Vienna observatory (photo to the right), accepting less pay (and certainly less prestige) in trade for being able to use Vienna's 27" refractor. At the time it was the world's largest telescope. There he made a further 94 asteroid discoveries.
How I got involved: I was at a dinner party Christmas night of 2008 and somehow got involved in a game of Trivial Pursuit. One of our geography questions was "What is the largest county by land mass". Somehow I had acquired a mistaken reputation of being 'smart' in these matters, and as my team turned towards me with expectant eyes, I blurted out..."China". Sigh. The correct answer is, of course, Russia. Anyway, that got me to wondering if there was a minor planet by that name, and looking into the matter I found that there was, but that there was only a partial lightcurve done at Geneva Observatory in Switzerland. Indeed, the Minor Planet Center doesn't list any data for 232 Russia, so it seemed like a worthwhile target.
I stand corrected (16 Feb 2009): Turns out that upon further review of the literature, I see that Torno, Oilver and Ditteon of the Rose-Hulman Institute of Technology in Terre Haute, IN did some work on 232 Russia in October of 2007. In an article in The Minor Planet Bulletin (April - June 2008 issue) they state that theirs may "be the first reported observations of the period of...233 Russia". Possibly the Geneva Observatory may have beaten them to that punch, but my goal is to complete the first full-coverage observations of 232 Russia.
232 Russia will be a bit difficult, as its period seems to be around 25 hours. Since earth rotates every 24 hours, we're only one hour 'out-of-sync' with 232 Russia. Fortunately, I'm in no hurry. I should have a preliminary light curve soon.
Update: March 5th...Russia is complete. Period 21.9 hours, P.E. 0.0100, 693 data points over 11 observing runs.
THESE WILL OPEN A NEW WINDOW: Full size plot - Full size plot with error bars
291 Alice - (completed 22 March 2009)
A member of the Flora 'family' of main-belt asteroids, 291 Alice is listed as a 'spin and shape modeling' target of opportunity in the Minor Planet Bulletin 36-1. It's published light curve data from Lagerkvist (1975), Kryszczynska (1996/2008), Piironen (1998), and Oey (2006) indicate a synodic period of roughly 4.32 hours.
My observational goal for 291 Alice is to obtain a sufficient quality and quantity of data to support spin and shape modeling. V-band observations are planned.
The Flora family of asteroids comprises about 5% of all known main belt asteroids. The largest member of the family is 8 Flora, a 140 kilometer (87 miles) diameter body that accounts for about 80% of the total family mass. Second largest is 43 Ariadne, with the remaining family members being fairly small. 291 Alice is about 15 kilometers (9 miles) in diameter.
291 Alice was discovered April 25th of 1890 by J. Palisa at Vienna (see 232 Russia above for details, same discoverer and location).
In the Fourth Edition of the Dictionary of Minor Planet Names (Schmadel, 1999) there are listed 122 minor planet names with 'unknown meaning' i.e. the naming citation didn't give an explanation for who, what or why the name was chosen. 291 Alice is one of them. To we Americans the feminine first name likely comes to mind, but Schmadel does point out that 291 Alice was named by the Societe Astronomique de France 'at the gracious invitation of the discoverer'. So we have a German making the discovery and a French committee choosing a name (given that fact alone it would probably be wise to throw in the towel on figuring this out, but if you've read this far you are a bit on the bored side anyway, so let's continue...). The original form of the name is Adalheidis (German). 'Alice' is from the Old French name Alis, which was a short form of Adelais, which came from the German Adalheidis just mentioned. The mystery to me is why the form 'Alice' would be chosen with all these more earthy choices were available.
What's not a mystery is (again, citing the Dictionary of Minor Planet Names, Fourth Edition) that of the 122 minor planet names with unknown meaning, 108 of those were discovered and/or named by either the Germans/Austrians (Osterreichers forgive me!) or the French, both or who are responsible for about 10% of all minor planet discoveries as of 1999. Ten percent of the total discoveries, yet 88% of the 'unknown meaning' names. Schmadel doesn't speculate on this lopsided affair (and probably neither should I).
RESULTS: A four session observing run was conducted during the period March 13 to 22, 2009. The last two sessions were ‘split’ over one night to negate the ‘meridian flip’ problem addressed by Miles and Warner (2009) in The Minor Planet Bulletin. The period found was 4.32 ± 0.02 h, consistent with all previously published results (e.g., Binzel and Mulholland, 1983).
1940 GO (5153) - (abandoned 23 April 2009)
No long-winded epistle about the name of this asteroid since, technically, it has no name. Apparently a name citation has never been offered up for it. Y. Väisälä at Turku (Finland) discovered it on April 9th, 1940.
Only one lightcurve has been published for it (Behrend 2008), stating a period of 4.58 hours. The uncertanity code is a '1', defined as "Result based on fragmentary lightcurves(s), may be completely wrong" (Harris et al. 2008).
Alas, after our unusually wet and cloudy spring, I can report no better results (see figure below).
The five nights of observations I was able to obtain reveal an unusual shaped lightcurve since there appears to be only one minimum. Is the other minimum lost in the noisy data? Could be. The asteroid is past the point where I can effectively observe it, so it now goes onto the long list of object to revisit in the future. While the plot shows a period of 7 hours, that could be completely wrong.
397 Vienna - (completed 18 September 2009)
Discovered December 19 1894 by Auguste Charlois at Nice (Charlois 1896), 397 Vienna was his 20th asteroid discovery. He would go on to discover seventy-nine more. Out of his 99 discoveries, thirty have names that can’t be reconciled with any know person or occurrence (Schmadel 1999). The subject of this study falls into the category of “the unknowns”. Vienna is one of the 34 discoveries of Charlois that were named by J. Bauschinger, the Director of the Astronomisches Rechen-Insitiut. Apparently Charlois let the ARI suggest names for these 34, whether he gave final approval of the names is not clear.
Only one lightcurve has been published (Harris and Young, 1983, Icarus 54, 59-109). My objectives in observing are twofold, 1) to confirm the 15.48 hour period published by Harris and Young, and 2) obtain data that will be useful in the future for spin-shape modeling.
RESULTS: With nearly 100% coverage, the synodic period looks to be 15.45 hours, plus or minus 0.05 hours. This is in good agreement with the 15.48 hours previously reported (see paragraph above). Results are being submitted to The Minor Planet Bulletin for publication.
990 Yerkes (completed 15 December 2009)
Named and discovered by G. Van Biesbroeck from The Yerkes Observatory at Williams Bay, Wisconsin. There is no published rotation data concerning this object that I've been able to find.
RESULTS: The data is noisy, but with nearly 100% coverage. Synodic period looks to be 24.45 hours, plus or minus 0.05 hours, but 16.20 hours can't be ruled out.
4156 Okadanoboru (abandoned 15 January 2010)
Noboru Okada was a Japanese amateur astronomer, photographer and mountain climber. He was involved with installing a 0.5m-telescope near Yatsugatake mountain. In January of 2002, he disappeared while climbing alone in the Hida mountain range in central Japan. Asteroid 4156 Okadanoboru was discovered by T. Kojima at the YCGO Chiyoda observatory (YCGO=Yamaneko Group of Comet Observers) on January 16th, 1988.
I've not really been able to figure out what rule the Minor Planet Center uses when deciding to put a space in a name. Anne Franke (5535 Annefrank), yes THAT Anne Frank, didn't get her "space", but Olaus Magnus (2454 Olaus Magnus) got his. So did the fictional James Bond (9007 James Bond). Doyan Rose (45073 Doyanrose) didn't get a space either. Not for want of trying. After submitting the name as it is properly spent, i.e. "Doyan Rose", the Small Body Naming Committee took out the space and demoted the big "R" to a little "r". My immediate and repeated protests were answered with, in effect, "Sorry, that's how we do things". And indeed it is. We have to be careful how we parcel out spaces after all.
I have not seen the naming citation for 4156 Okadanobor, but given the gentlemen's first name was Noboru and the first and last names are inverted and missing the space, well, hard to say what is up. I'll dig up the naming citation one of these cloudy nights and see what the deal is. In the meantime, I'll be trying to get a handle on its rotation period.
UPDATE 15 January 2010 - time to throw the towel in on this one. The usual patter of winter weather (clouds, punctuated by more clouds) has granted few opportunities to gather a sufficent amount of data. Earth is now pulling well ahead of it, and as the distance between the asteroid and us increases, it gets fainter.
Current Project - 1317 Silvretta
1317 Silvretta became a target of opportunity one night when Okadanoboru (see immediately above) was unavailable due to the position of the Moon. A quick check of the Lightcurve Data file on the CALL site (http://www.minorplanetobserver.com/astlc/default.htm) showed a discrepancy in the reported rotation period. Schober ((Schober, H.J.; Schroll, A. (1983) Astron. Astrophys. 120, 106-108.)) published a rotation period of 7.048 h and a quality code of 3. Behrend (http://obswww.unige.ch/~behrend/page1cou.html) published data in 2009 stating a period of 3.86 hours, but with a quality code of 1+. It seems worthwhile to try and resolve this inconsistency.
1317 Silvretta was discovered on September 1st, 1935 by Karl Wilhelm Reinmuth at Heidelberg. The photo at right shows the Landessternwarte Heidelberg-Koenigstuhl, the observatory complex where Reinmuth worked. The dome that is open on the left shows the Bruce double-astrograph, used by Max Wolfe to discover 343 Ostara, as well as hundreds of other minor planets. The name Silvretta refers to a mountain range that spans the Austrian-Swiss border.
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