Official IAUC guidelines in case of discovery.

Circulars No. 6736, 6737, 6739 NOTICE TO CONTRIBUTORS Over the course of twelve hours on Sept. 6 UT the Central Bureau received two reports---purportedly independent---of the CCD discovery of an alleged supernova in NGC 772. Each indicated that the object was of mag 15-16, but the first was offset some 2' northeast and the second some 2' northwest of the center of the galaxy; the first observer did not record the observation time, but this image was evidently obtained some 26 hr before the second observer's image was obtained. Each observer noted that the alleged supernova was not present on images from earlier nights and that it did not move over the course of an hour or two; furthermore, the first observer remarked that two different checks for known minor planets in the vicinity did not reveal a match. The second observer indicated that this report had also been sent to selected other observers, with a note that "spectroscopic confirmation was requested". On receipt of the information from the first observer, a check at the Central Bureau immediately revealed that, although the observation time had not been specified, the alleged supernova northeast of the galaxy was probably minor planet (5240), then very close to its morning stationary point and in fact still moving very slowly eastward. This information was relayed to the observer. Nevertheless, within six hours of this (i.e., still two hours before the second observer's image was obtained), a copy of the first observer's image was present in the World Wide Web, together with the mention (though without details) of an apparent confirmation by the webmaster. Measurement of the WWW image at the Central Bureau clearly confirmed the indicated identity of the "supernova" with (5240) and allowed the observation time to be specified. In the Bureau's message to the first observer, it was also mentioned that minor planet (1887), comparable to (5240) in brightness, was near the galaxy. Examination of the WWW image showed that (1887) would have been just off the southern edge at the time of observation. Nevertheless, (1887) was moving northward at five times the rate of (5240), and it had already begun its westward motion. On receipt of the second report of an alleged supernova, with the indication that it was 125" west and 75" north of the center of the galaxy, it was then immediately clear that this observation in fact referred to (1887). The above account is given in some detail because it allows several points to be made. These will be discussed on IAUC 6737, together with a proposed remedy for the problem. NOTICE TO CONTRIBUTORS The following points can be made concerning the account on IAUC 6736. Firstly, some sources of information about minor planets are apparently unreliable. Secondly, apparent absence of motion over the course of less than several hours of an object near the ecliptic is not a guarantee that a minor planet has not been observed, particularly if it is near a stationary point. Thirdly, spectroscopic confirmation by professional astronomers using large telescopes is an expensive proposition and should be considered only as a final resort. Fourthly, the use of the WWW for confirmation purposes is potentially dangerous, in that if the Central Bureau is not cognizant of who knows of a purported discovery, a genuine discoverer could conceivably be deprived of credit. In the specific case of a CCD or photographic detection of an apparent supernova and nova, observers are henceforth requested, before making a report, to perform at least three of the following four tasks, if credit is expected for a discovery. Firstly, they should make a precise astrometric measurement of the object's position, specifying date and time (and magnitude); secondly, they should also observe on a second night to verify that the object is in precisely the same location; thirdly, they should show that the object was not present on comparable images on some other occasion; fourthly, they should clearly demonstrate the object's nature from its spectrum. The first two points, in this case showing motion, are routinely expected of CCD and photographic discoverers of minor planets and comets. We recognize that the fourth point is difficult for all but experienced professional astronomers, but amateurs can still perform the first three. We also recognize that the first two points, and maybe even the third, represent a problem for visual discoverers, although a visual supernova hunter, in particular, can in this instance clearly profit by collaborating with a colleague who utilizes a CCD. If bad weather is expected, it may also be reasonable for a CCD observer to collaborate with a colleague elsewhere for the second-night follow-up, but this should be a trusted colleague who is contacted personally, not someone who responds to a mass e-mailing or WWW placing. The proliferation of internet communication greatly reduces the security involving requests for confirmation, particularly when the CCD images themselves are posted. This point was discussed at length at the meeting of IAU Commission 6 in Kyoto last month, in that such extensive use of the internet could completely jeopardize what is meant by a discovery and the proper assignment of credit. The matter is of particular import in the case of comets, because the IAU clearly wishes to continue the tradition of naming these objects for their discoverers. NOTICE TO CONTRIBUTORS AND SUBSCRIBERS Some respondents have expressed worry that the procedure given on IAUC 6737 for reporting CCD and photographic discoveries of supernovae and novae will incur delays in announcement that could jeopardize significant scientific results. For some years we have been routinely relaying all remotely promising reports privately to spectroscopists for confirmation, and almost every observer in the world able and willing to make these confirmations is on our list. The delay is in securing spectroscopy. By accepting discoveries on the basis of compliance with the first three requirements (accurate position, second-night confirmation, nonappearance on appropriate earlier images), we hope to be able significantly to reduce the delay--albeit at the expense of occasionally announcing observations of some unknown long-period variable star instead. With a record 109 genuine supernovae already recognized in 1997 (in addition to numerous false alarms), some organization of the activity is clearly essential if it is to remain manageable. Proponents of the use of e-mail exploders and the WWW for the widespread dissemination of incomplete and uncertain reports suggest that such use provides more of a guarantee that "science" can be done, conducted in a timely manner, and that nothing will be lost. Even if an occasional imperfect report could be salvaged in this way, the whole process is extraordinarily inefficient and carried out with an enormous "spinning of wheels" by hundreds of participants. A lofty scientific ideal is all very well, but complaints would surely be rampant if the confusion led to misplaced credit for a discovery. Several serious observers have also mentioned that they would be embarrassed to publicize in the internet claims that might be erroneous. It has been proposed that those who disseminate discovery reports in the internet should be sure also to inform the Central Bureau; it would also help if those who do contact us were to let us know if they have also distributed their reports widely to others. One point on IAUC 6737 referred to the unreliability of some sources of positional information about minor planets. The most longstanding electronic source for listing the minor planets in a particular region of the sky at a given time is the CBAT/MPC Computer Service, which has reliably provided this information for the numbered minor planets for well over a decade. A new version of this feature, freely available in the WWW at http://cfa-www.harvard.edu/ps/CheckSN , also includes many unnumbered minor planets (although for these the data are not fully guaranteed). While a general-purpose facility, it is particularly suited for checking candidate supernovae, for it will show the minor planets in the vicinity of a specified M, NGC, IC, UGC or MCG galaxy at the time in question.