Probably off-topic, but anyway: ************************************************************************* Dear Project Manager or Scientist, It is being proposed to change the definition of Coordinated Universal Time (UTC) regarding the insertion of leap-seconds, possibly even eliminating their use. Leap seconds are introduced so as to keep UTC synchronized (within 0.9 s) to the time scale determined from the Earth's rotation, however many practical problems result from their implementation. Should no new leap seconds be inserted, solar time will diverge from atomic time at the rate of about 2 seconds every 3 years, and after about a century |UT1-UTC| would exceed 1 minute. Although no fundamental problems are anticipated, it is very likely that Y2K-like problems may result in software that assumes UT1=UTC, or |UT1-UTC|< some value, or whose input/output records use a field size that can only accommodate |UT1-UTC| values up to one second. To gather information, an URSI Commission J Working Group was formed, consisting of Don Backer, Wim. N. Brouw, Barry Clark, Irwin Shapiro, Ir. E. Van Lil, and myself. We would like to ask you to consult with the members of your institute who currently deal with UT1-UTC, and give us a considered response to the following two questions: A. If the appropriate international bodies decide to eliminate the insertion of new leap seconds, would you foresee any practical problems for your institution/instrument/observations? no ____ * yes ___ * possibly ____ (* please explain any known or possible problems) B. Would you be in favor of such a proposal? yes ____ no ____ indifferent ___ have better idea ___ (feel free to comment) C. Is there anyone else you would recommend we contact? (feel free to forward this eamil directly) I would appreciate your assistance, and a response by January 15 to dnm@orion.usno.navy.mil. [snip] Sincerely, Demetrios Matsakis ________________________________________________________________________ Dr. Demetrios N. Matsakis Director, Time Service Department (202) 762-1587 DSN 762-1587 U. S. Naval Observatory FAX (202) 762-1511 3450 Massachusetts Avenue NW dnm@orion.usno.navy.mil Washington DC, USA 20392-5420 ________________________________________________________________________