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#1
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Hello all,
I have run into a few older papers that have some angular measure notation with which I'm unfamiliar. For example, 0.'25 and 0."25, with the quote marks directly over the decimal point in each case. I suspect that these denote 25 arcmin and 25 arcsec respectively, but I'd like to be sure about that. Can anyone confirm what this notation is supposed mean? Thanks! -- Dave |
#2
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Chris L Peterson wrote:
On Wed, 17 Mar 2010 10:43:07 -0400, Dave Typinski wrote: I have run into a few older papers that have some angular measure notation with which I'm unfamiliar. For example, 0.'25 and 0."25, with the quote marks directly over the decimal point in each case. I suspect that these denote 25 arcmin and 25 arcsec respectively, but I'd like to be sure about that. I'm sure your interpretation is correct. It is a common style to attach units to the integer part of a value. You see it in new papers as well, although the trend is definitely away from it. In astronomy, it also shows up in other notation, such as RA = 5h.3 (with the 'h' superscripted). Thanks, Chris. Yes, I did see that sort of notation for RA. I ran into the tickmarks-on-the-integer oddity in a Soviet paper from 1964; I wasn't positive that it wasn't some form of grad measure notation. Thanks for clearing that up. -- Dave |
#3
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On Mar 17, 7:43 am, Dave Typinski wrote:
I have run into a few older papers that have some angular measure notation with which I'm unfamiliar. For example, 0.'25 and 0."25, with the quote marks directly over the decimal point in each case. I suspect that these denote 25 arcmin and 25 arcsec respectively, but I'd like to be sure about that. I'm almost certain the correct interpretation is 0.25 arc-minutes (i.e., 15 arc-seconds) and 0.25 arc-seconds, respectively. I don't know where you might find a definitive reference to resolve the confusion, but I've seen this notation used on occasion, and I'm fairly sure that's how it works. Are there any examples listed in the papers that you might compare to known values as a sanity check? -- MC -- |
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On Wed, 17 Mar 2010 10:43:07 -0400, Dave Typinski
wrote: Hello all, I have run into a few older papers that have some angular measure notation with which I'm unfamiliar. For example, 0.'25 and 0."25, with the quote marks directly over the decimal point in each case. I suspect that these denote 25 arcmin and 25 arcsec respectively, but I'd like to be sure about that. Can anyone confirm what this notation is supposed mean? Thanks! I think it means a decimal fraction of a minute of arc or a second of arc. Bud |
#5
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Dave Typinski wrote:
Chris L Peterson wrote: On Wed, 17 Mar 2010 10:43:07 -0400, Dave Typinski wrote: I have run into a few older papers that have some angular measure notation with which I'm unfamiliar. For example, 0.'25 and 0."25, with the quote marks directly over the decimal point in each case. I suspect that these denote 25 arcmin and 25 arcsec respectively, but I'd like to be sure about that. I'm sure your interpretation is correct. It is a common style to attach units to the integer part of a value. You see it in new papers as well, although the trend is definitely away from it. In astronomy, it also shows up in other notation, such as RA = 5h.3 (with the 'h' superscripted). Thanks, Chris. Yes, I did see that sort of notation for RA. I ran into the tickmarks-on-the-integer oddity in a Soviet paper from 1964; I wasn't positive that it wasn't some form of grad measure notation. Thanks for clearing that up. -- Dave As other posters have pointed out, the correct interpretation is 0.25 arc minutes for the first example, 0.25 arc seconds for the second. It's common enough that AASTeX has defined macros for these. I suspect that the motivation was to save one column, back in the days when star catalogs were typed and columns were precious. -- Bill Owen |
#6
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On Mar 17, 8:43*am, Dave Typinski wrote:
Hello all, I have run into a few older papers that have some angular measure notation with which I'm unfamiliar. For example, 0.'25 and 0."25, with the quote marks directly over the decimal point in each case. I suspect that these denote 25 arcmin and 25 arcsec respectively, but I'd like to be sure about that. * Can anyone confirm what this notation is supposed mean? I would have thought that these would mean 1/4 of an arcminute and 1/4 of an arcsecond respectively. I know I've seen it used in that sense. John Savard |
#7
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Bill Owen wrote:
Dave Typinski wrote: Chris L Peterson wrote: On Wed, 17 Mar 2010 10:43:07 -0400, Dave Typinski wrote: I have run into a few older papers that have some angular measure notation with which I'm unfamiliar. For example, 0.'25 and 0."25, with the quote marks directly over the decimal point in each case. I suspect that these denote 25 arcmin and 25 arcsec respectively, but I'd like to be sure about that. I'm sure your interpretation is correct. It is a common style to attach units to the integer part of a value. You see it in new papers as well, although the trend is definitely away from it. In astronomy, it also shows up in other notation, such as RA = 5h.3 (with the 'h' superscripted). Thanks, Chris. Yes, I did see that sort of notation for RA. I ran into the tickmarks-on-the-integer oddity in a Soviet paper from 1964; I wasn't positive that it wasn't some form of grad measure notation. Thanks for clearing that up. -- Dave As other posters have pointed out, the correct interpretation is 0.25 arc minutes for the first example, 0.25 arc seconds for the second. It's common enough that AASTeX has defined macros for these. I suspect that the motivation was to save one column, back in the days when star catalogs were typed and columns were precious. Thanks, Bill (and Chris and MC and Bud and John)! Very helpful! -- Dave |
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