"In-testing" update to Guide 9.0

Last updated 2015 July 27

You can click here for the current "test" update to Guide 9.0 UnZIP its contents to your Guide folder; this will overwrite some files and create some new ones. That should be all Guide 9.0 user have to do.

Note that it's also possible to use the update with Guide 8.0! Things get a little trickier (though not much so); click here for details.

Italian users should also click here for some updated Italian files (about 76 KBytes). UnZIP the contents into your Guide folder; three files will be replaced or added.

(2015 July 27) Overlay bugs fixed: Christian Ambros reported crashes when attempting to edit overlays. That caused me to look through much of the overlay code, and to find a particular bug that probably caused crashes in other areas as well. That bug is now fixed.

(2015 May 14) Two moons of Pluto added: Guide already had the three largest moons of Pluto: Charon, Nix, and Hydra. It now also has the remaining two moons, Kerberos and Styx. (Quite a bit of updating needs to be done to include a slew of other recently found moons, but Kerberos and Styx are something of a priority, with New Horizons due to arrive at Pluto in two months.)

To get these to show up exactly where they should (and to update the positions of Nix and Hydra to reflect the current best guess as to where they are), click here for current ephemerides. UnZIP the file (it contains four files of extension .b32) into your Guide folder.

This update will also "fix" a really obscure problem that we really shouldn't even be having to worry about, that fell out from the reclassification of Pluto as a "dwarf planet". Planets, in the view of the IAU, can rotate either "forward" or "backward"; the key thing is that the north pole has to be above the plane of the ecliptic. Dwarf planets and asteroids, on the other hand, always rotate in a "forward" (prograde) manner, even if that puts the north pole below the ecliptic.

So, with the reclassification, Pluto and Charon's rotations and poles now have the opposite signs as they did back when they were planets, and Guide now reflects this bit of silliness.

(I will note that, despite the name of my company, I don't really care much about the definition of "planet" vs. "dwarf planet" vs. "minor planet". It is about as interesting or important, to me, as the distinctions between "rocks", "pebbles", and "boulders". But I do wish these semantic arguments could be conducted without making the already weird planet orientation conventions still weirder.)

(2015 May 14) Leap second added at end of June 2015: The Time Lords in Paris, at the International Earth Rotation and Reference Systems Service, who decide such matters have decreed that at the end of 2015 June 30, a leap second will be inserted. The new version includes that leap second.

(2014 April 17) Locating UCAC-4 stars added: If you use Go To... Object Name, you can now enter (for example) 4U314-15926 to find that object. (Prefixes '4U' and '4UC' will both be accepted. The former is technically not correct; apparently, they wanted to use '4U', but somebody else had already laid claim to it. Still, '4U' gets plenty of use.)

Note that this does assume that you have set up UCAC-4 display as described elsewhere on this page.

(2013 December 12) Bug in refracted separation fixed: It was pointed out on the Guide user list that if you had the "Refraction" check-box ticked in the Locations dialog, and then tried to measure the angular separation between two points, the program would lock up if either point was below the horizon. This happened with both methods of measuring angular separation: dragging a line between the two points with the right mouse button, or clicking on two objects and then hitting Insert to get the exact separation and position angle.

This bug is now fixed. If refraction is turned on, and you ask for a separation/position angle for two points above the horizon, you'll get the usual airless data, plus the refracted separation. (If either point is below the horizon, you won't get refracted data.)

(2012 December 12) Fixes/improved display of comets: Several people have reported issues with displaying comets in Guide. Some of these are issues that have been around for a while. Comets often get displayed twice, once with a preliminary designation such as "C/2012 V4", and again with a permanent designation such as "273P"; Guide can't tell that they are the same comet. If you don't update frequently, you can lose comets that appeared briefly during the time you weren't updating comets. Guide had some very complicated logic in it to handle these situations, and in some cases, this led to crashes.

It was very difficult (nearly impossible!) to edit comet elements, because the list of comets tended to be enormous. It really should start out containing just a "(new asteroid)" and "(new comet)" entry (and with this update, it does.)

Also, there have been problems recently because the MPC provided large lists of "critical asteroids" and NEOs. Guide wasn't really expecting to handle such updates in this manner; the expectation was that people would use MPCORB for this purpose, thereby updating all their asteroids at once. With the current update, the controls in Guide to update asteroids are gone; the only way to do it is to use MPCORB. This should eliminate a lot of crashes and other misbehavior.

Comet updates are now handled by getting data both from the Minor Planet Center and from the IMCCE (formerly the Bureau des Longitudes, in Paris). Patrick Rocher of the IMCCE is computing orbital elements for comets, and has a fairly comprehensive list for objects found since about 1995.

Guide will first display any comets whose orbital elements have been entered by the user with Extras... Asteroid/Comet Options... Edit Comet Data. (Typically, this will mean zero comets.) It will then display comets from MPC's list, then the IMCCE list, then its own built-in list from the DVD. The reason for this is that the MPC data is updated pretty frequently. The IMCCE list is sometimes a week or two out of date. The built-in list doesn't get updated at all, but will be used only for comets tracked before 1995 (i.e., if you ask about the Great Comet of 1811, that's the data Guide will use.)

(2012 August 3) UCAC-4 display: The UCAC-4 catalog has now been released, on a double-sided DVD; click here for details. You can, with a little effort, persuade Guide to use this data instead of the default UCAC-3. The process is very similar to that used to get UCAC-3 display in Guide 8. Copy all files from both sides of the UCAC-4 DVD to your hard drive. (This will consume about 8.8 GBytes.) You can copy the data just about anywhere; as an example, let's assume you used the path c:\ucac4. You would then start up Guide and hit Alt-J. Guide will prompt you for a "test flag". You would enter


(modifying the path to the files to match what you actually used). Note that UCAC4_PATH must be in capitals, and don't add spaces around the equals sign!

After you've done this, Guide will switch to use of UCAC4. Note that this is displayed as a "user-added dataset", and UCAC4 will (by default) only appear when you zoom in to fields of under a degree. You can adjust that limit, and toggle UCAC4 on/off, with Extras... Toggle User-Added Datasets. Look for UCAC4, and double-click on it. (I recommend doing this if UCAC4 fails to appear; check to make sure it's turned on, and that the "shown at" fields of view include your current field of view.)

Note also that it's possible to show UCAC4 running off the files on the DVD. Suppose your DVD drive is d:. You would put the DVD in the drive, hit Alt-J, and type UCAC4_PATH=d:. This will be somewhat slower than running from hard drive, though, and you'll only get half the sky at any given time (with the other half on the flip side of the DVD.)

(2012 January 16) Ability to enter times using the "alternative" time zone: One can go into Display... Legend, and tick the "Second Time" check-box, to get the time displayed in the legend in a second manner. Leaving the first time in, say, YYYY/MM/DD HH:MM:SS form in the Gregorian calendar in your local time zone, you can have the second time displayed in some completely different format: perhaps as decimal days in the Chinese calendar, using local apparent solar time. (More likely, you might just use it to show the time in UTC, or to show local sidereal time if you were using setting circles, or something of that sort.)

Anyway. One can now click on the "alternative" time and enter a time that will be assumed to be in that zone. For example, if your "normal" zone is Eastern US, but the "second time" is LAT, you can click on the second time, enter 12:00, and Guide will find local solar noon. (But note that with the new ability to specify a time zone when entering a time, you can always enter "12:00 LAT" and Guide will recognize that you want a LAT time, not a default-zone time. You don't absolutely need to use the second time zone to get this functionality.)

(2012 April 6) New and Improved handling of Delta-T: Guide now uses somewhat better approximations for "ancient" (before 1620) values of Delta-T, and the ability to define one's own Delta-T functions has been improved. Click here for details.

(2012 April 6) New and "Improved" handling of UTC: I put "Improved" in quotes, because no matter what one does with UTC (Universal Coordinated Time, the standard for civil time throughout the world), it's still not very good. But Guide's handling of it is, I hope, better than it was.

The basic issue is this. The length of UTC seconds is set by atomic clocks, which are designed to be as "regular" as possible. But UTC is to be synchronized to the earth's rotation, which isn't quite regular. To keep UTC in synch with the earth, a "leap second" must be inserted at irregular, unpredictable intervals, at the end of June or the end of December. One is due to be inserted at the end of June 2012; one of the fixes in this update is that this leap second is taken into account.

We can therefore be confident that UTC is a well-determined time system until the end of December 2012. It's unlikely that a leap second will be inserted then, but one doesn't know until an announcement is made. So when Guide gives a UTC time for the future, it's something of a guess.

It was pointed out to me recently that Guide's concept of "future" UTC was to assume no leap seconds would be inserted. This is clearly and flagrantly wrong. We don't know exactly when they'll be inserted, but there is an approximate expression that assumes a linear slowing down of the earth's rate of rotation, ignoring the (unpredictable) deviations from that linear slowdown. The "improvement" in this update is that Guide's formula for UTC will insert leap seconds so as to best match the predicted Delta-T value. (Which also means that if you adjust Guide's formula for future Delta-T -- click here for details on how to do that -- the values for future UTC will be similarly adjusted.)

At present, using its default Delta-T algorithm, Guide inserts a leap second at the end of 2014 and 2017, and then in mid-2020. Leap seconds will probably occur within six months or so of those times. Maybe even exactly at those times. But you can never tell with UTC.

Even worse things happen centuries in the future. This algorithm inserts two leap seconds at the end of 2276, and still more leap seconds at the end of June and December centuries later. I assume that before then, UTC will be thrown out and something better used.

Incidentally, the uncertainties in Delta-T for ancient dates are not a concern here. UTC is computable for dates after 1961 January 1. Before that date, UTC is completely undefined, and Guide assumes UT=UTC.

Note that this is all an horrible, ugly kludge. But then again, UTC itself is an horrible, ugly kludge.

(2012 April 6) Bug in rendering of Venus (and other retrograde objects) fixed: John Boudreau, Mike Mattei, and Hans-Goran Lindberg pointed out, on the Venus_watch Yahoo group, that Guide's display of Venus appeared to have reversed east and west. Venus (and other retrograde objects: Uranus, Pluto, and their moons) have caused grief over the years, because of a truly boneheaded convention implemented by the IAU. One side effect of this convention is that positive longitudes are west on most objects, but east on retrograde ones. Thus, one has a right-handed coordinate system on prograde objects, and a left-handed one for retrograde ones. Which makes for many opportunities for confusion.

When Venus was shown in Guide, the features and bitmap were both flipped; objects at, say, longitude E 27 were shown at longitude W 27. The readout under the cursor was also flipped in the same manner, with E and W interchanged. There was also a problem introduced by me: Guide would sometimes use "System II" longitudes for Venus. "System I" is the most commonly-used system, corresponding to the motion of Venus' surface, which rotates once every 243 days relative to the stars. "System II" rotates once every 4.2 days, and is a good match to the motion of the clouds covering Venus.

These problems are all fixed now. The labelled features, and maps showing the surface of Venus (including the new map mentioned below), are synched to System I. If you're showing one of these maps, the cursor readout will give a System I longitude. The "cloud" bitmap is in System II, and when shown, the cursor readout will be in System II. This does mean that if you animate Venus with clouds and labelled surface features shown, the clouds will rotate every 4.2 days, and the labelled features much more slowly. But that happens to reflect reality.

(2012 April 6) New Venus map: At least one good thing did come out of the confused rendering of Venus described above: I wound up converting the second Venus image provided on Steve Albers' planetary map site into the .qwe form used in Guide. (Guide already showed the first, shades-of-orange radar map.) You can click here to download the new Venus map (about 1.3 MBytes). UnZIP it in your Guide folder, right-click on Venus, and then on Display... Options. You'll see that you can show a "cloud" map, a "radar image", and a "radar/topo image". That last is the new map.

(2012 April 6) Bug in star magnitude labels fixed: If you went into Display... Star Display, and set a "mag label" limit of, say, 6.5, then all stars brighter than mag 6.5 should be labelled by their magnitudes. Unfortunately, if zoomed in a bit, this turned into all stars, regardless of brightness. This is fixed.

(2012 April 6) Bug in TLE selection fixed: It was reported, on the Guide user list, that when you asked to select a TLE (Two-Line Element file, for artificial satellite display), the resulting dialog didn't list the existing TLEs. This has been fixed.

(2012 April 6) Bug in asteroid display fixed: Gerhard Dangl pointed out, in a message on the Guide user list, that when Guide encountered asteroids with no magnitude data, it assumed H=0.15 and G=0.0, meaning it assumed that the object was truly immense. Not many objects have no magnitude parameters; the cases I've seen involved objects observed solely by the WISE satellite, whose magnitudes (all in the infrared) were not reported to MPC. I've revised Guide to assume that such objects are quite faint, only to be shown when asteroids are turned On.

(2012 January 29) Lunar phase indicator fix in legend: At the suggestion of Pete Gladstein and Stephen Tonkin, the lunar phase indicator is now a separate option in the Legend dialog. So you can have a compass indicator, the lunar phase indicator, or both or neither.

One small benefit of this is that if you do have the lunar phase indicator showing, you can right-click on it to find the Moon and left-click on it to find the Sun.

(2012 January 29) Apparent diameters available in ephemerides: When making ephemerides, you can click on Ephemeris Items and see "App Diam" listed in the resulting dialog. The apparent diameter is shown in arcseconds. Note that this works (at least right now) only for planets, satellites, and the Sun.

(2012 January 16) Fix to some problems in entering/displaying times: Luc Desamore pointed out that there were bugs in the Settings... Enter Time feature. For example, were one to enter any of the following:

2012 jan 16 13:14
3/13/1977 15:00
6 mar 10:12:17

(click here for details as to the ways in which times can be entered), you'd expect Guide's default time zone to be used. On the other hand, a JD or MJD really ought to be on Universal Time, no matter what. (Unless you've specified TD = Dynamical Time, in which case you'd expect that system to be used.) But the latter didn't happen. If you entered, say, JD 2451545, you'd expect the result to be noon UT of a particular day. Instead, you got noon local time of that day.

This is now fixed. (Note that JDs and MJDs default to being UT no matter what, even if the default "time zone" is TD.)

Also, Luc noticed that the JD shown in Quick Info was put into local time. It is now always a UT JD.

(2012 January 16) Ability to enter time zones when entering times: Something that fell out of the above bug fix: I usually run Guide with UT (Universal Time) as the default time zone. If I want to set Guide's time to, say, 3:14:15.9 Eastern Daylight Time (EDT) or 12:34:56 Dynamical Time (TD), I've had to change the default time zone, enter the desired time, and then switch back to UT.

Now, when using Settings... Enter Time, one can specify a time zone, which you couldn't do before. For example:

3:21:16 UT
03:14:15.9 EDT
12:34:56 td 

now behave properly, with the time zone extracted from the end of the text. (Otherwise, the default time zone is assumed, unless you enter a JD or MJD, in which case UT is assumed.)

Incidentally, one can also now use PM, P.M., p.m., AM, etc. to indicate 12-hour-clock times; and one can start the time string with 'now', to do things such as

now 3:00 PM EDT     (15:00 Eastern Daylight Time today)
4:15 a.m.           (4:15 in currently-set time zone,  leave day unchanged)

(2012 January 16) NSV finding fixed: Roger Pickard pointed out that using Go To... Star... NSV... 134, or using Go To... Object Name and entering "nsv 134", failed. The same thing happened for every NSV star that has received a GCVS variable star designation (which includes a lot of them). This has been fixed.

(2012 January 16) Fix to colors used in Great Red Spot transit time tables: Pete Gladstein pointed out that the GRS transit times shown in "More Info" when Jupiter is clicked on, as well as those shown by the Tables... GRS Transits function, are always red. They really should follow the common Guide scheme in which red means the object is below the horizon, yellow means it's less than ten degrees from the horizon, and green means it's above ten degrees in altitude. This is now fixed.

(2012 January 16) Lunar phase indicator shown in Legend: If you have the Compass item shown in the legend area, you'll see a lightly overlaid outline of the moon's current phase.

(2012 January 16) 2012 July 1 leap second inserted: Of concern mostly to precision nuts: it was announced recently that a leap second will be inserted into UTC at the end of June 2012. That is to say, 2012 June 30 23:59:59 will be followed by 2012 June 30 23:59:60, which will be followed by 2012 July 1 0:00:00. (Leap seconds are inserted at the end of June or December at irregular and unpredictable intervals, in order to keep UTC in synch with the slightly irregular and unpredictable rotation of the earth.) This leap second is now included by Guide when computing UTC times.

Updating from Guide 8.0: (Guide 9.0 users should ignore the following!)

• Before installing a 9.0 update, you have to make sure that you have the last Guide 8.0 update. To check this, run Guide 8.0 and click on Help... About Guide to check the version date. If it is not 2011 Aug 16 or later, then you aren't up to date on Guide 8.0; click here to get it. Install it (basically, save the contents of the guide8.zip file in your Guide folder, overwriting some files and creating others.)

• Then click here for the current "test" update to Guide 9.0 for Guide 8.0 users, and unZIP its contents into your Guide folder, too. Again, this will overwrite some files and add others.

• Note that this gets you the current Guide 9.0 software. (It'll even say "Guide 9.0" on the application title bar.) So you'll get the improvements mentioned above, but not the updated asteroid elements, star and galaxy catalogues, and so forth that require the gigabytes of data on the Guide 9.0 DVD. For that, you should click here for information on ordering Guide 9.0.