David's Astronomy - Notes 2020-05-24 (S00784)

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Notes - Session 784 (2020-05-24)

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(S783)

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Notes
(S785)

	2020-05-25

	Session Aims & Highlights
	- Observing Result - Night Summary Plot - Session Event Log

	Operational Issues
	- Critical Issues (0), Major Issues (0), Minor Issues (14), Continuous Improvement (8)

	Images from 2020-05-24 >>

	Pegasus UPB - v1.6.0
	TCF-S - Focus Temperature Compensation (12" LX200)

Session Aims & Highlights (2020-05-24)

Main aims

Software Testing: Test new 3.22.3 version of AstroMain which has had multiple changes since 3.22.1. Check for absence of introduced bugs or new issues. Check bug fixes and new features/enhancements
Targets: Acquire images of a number of targets if conditions allowed. Weather conditions forecast to be marginal.

Equipment & Software

12" LX200 and ST-10XME
80mm APO and ZWO ASI 178MC
CCDApp2, TheSky6, CCDSoft5, PHD2, POTH Hub
Pegasus UPB & Motor Focus, TCF-S
SharpCap 3.2, PHD2 2.6.8
AstroMain 3.22.3, AstroGuard 1.2.11, AstroPlan 1.15.1, AstroShCap 1.2.22, AstroVOE 1.3.6, UPB 1.5
(AstroWeather 1.9.8, AstroAllSky 3.5.1)

Highlights

Software Testing. Testing of new 3.23.1 version of AstroMain was largely successful. No major issues were found and the majority of bug fixes/ new features in new version worked well.

Lowlights

Foc2 Focus / Guiding. Foc2 focusing couldn't be achieved on either of the two attempts made. Poor focus led to relative poor guiding.

Summary Plots & Logs

Observing Plan

Observing Result

Dome & Scope Slewing Performance

Slew/Centering Performance

Guiding Performance

Sky Conditions (Locate Frames)

Night Sky Summary Plot
Top axis: Sky Brightness at Zenith (in ADU/s)
Lefthand axis: Local Time (hh LT). Righthand axis: Sun Altitude (degs)

Pre-Session Weather Forecast (API data from darksky.net)
Pre-Session Weather forecast showed variable skies range from 5 to 50% cloud cover,
light winds (wind 7mph) and a minimum temperature of 6°C.

In the event conditions were clear and calm through the whole night, with a minimum temperature of around 4°C

Session Event Log

Time	Event	Detail
23:38:20	Camera1 Connected	SBIG Camera Connected (set point -15°C)
23:38:22	Session Created	Live Session Created (2020-05-24 S00784, ImageSaveNum: 784001)
23:38:39	Scope Switched On	Telescope Power has been switched on via UPB Powerbox.
23:40:21	Services Started	Observatory Services started
23:40:54	Observatory (Auto)	Observatory placed in Fully-Automated Mode
23:40:57	Session Pending	Session pending (2020-05-24)
23:40:59	Session Initiating	Session initiating (2020-05-24)
23:41:01	Plan Requested	Observing Plan requested from AstroPlan (1.15.1)
23:41:37	Plan Loaded	Observing Plan loaded to queue (2020-05-24 V1 BEST PLAN, Plan ID: 513)
23:41:40	Camera1 Connected	SBIG Camera Connected (set point -15°C)
23:41:46	Telescope Connected	Telescope Connected (TheSky6)
23:41:58	Session Equilibration	Session ready for dome & camera equilibration
23:42:44	Shutter Opened	Shutter opened (opening time 47s)
23:42:47	Equilibration Started	Dome Equilibration started
23:46:48	Equilibration Ended	Dome Equilibration ended (4.1 mins total)
23:46:50	Session Running	Session running
23:46:52	Queue Started	Observing Queue started (11 targets selected)
23:48:16	Target Started (1/11)	Target started (1/11, UGCA 317)
23:52:13	Focusing Started-Foc1	Foc1 Focusing Started (TCF-S)
23:55:16	Focusing Completed	Foc1 AutoFocus Completed (Profile No 1)
00:10:57	Target Completed	Target completed (1/11, UGCA 317)
00:10:59	Target Started (2/11)	Target started (2/11, PGC 49584)
00:13:00	Focusing Started	Foc2 Focusing Started (Secondary Scope, using ShCap)
00:14:00	Focusing Started-Foc1	Foc1 Focusing Started (TCF-S)
00:16:50	Focusing Completed	Foc1 AutoFocus Completed (Profile No 2)
00:32:53	Target Completed	Target completed (2/11, PGC 49584)
00:32:55	Target Started (3/11)	Target started (3/11, NGC 5609)
00:35:11	Focusing Started	Foc2 Focusing Started (Secondary Scope, using ShCap)
00:36:22	Focusing Started-Foc1	Foc1 Focusing Started (TCF-S)
00:38:57	Focusing Failed	Foc1 Focusing Failed - star lost
00:55:02	Target Completed	Target completed (3/11, NGC 5609)
00:55:04	Target Started (4/11)	Target started (4/11, GCVS R CrB)
00:58:22	Focusing Started-Foc1	Foc1 Focusing Started (TCF-S)
01:00:57	Focusing Completed	Foc1 AutoFocus Completed (Profile No 4)
01:03:54	Target Completed	Target completed (4/11, GCVS R CrB)
01:03:56	Target Started (5/11)	Target started (5/11, UGC 11320)
01:07:52	Focusing Started-Foc1	Foc1 Focusing Started (TCF-S)
01:11:13	Focusing Completed	Foc1 AutoFocus Completed (Profile No 5)
01:27:14	Target Completed	Target completed (5/11, UGC 11320)
01:27:17	Target Started (6/11)	Target started (6/11, GCVS CY Lyr)
01:30:05	Focusing Started-Foc1	Foc1 Focusing Started (TCF-S)
01:32:57	Focusing Completed	Foc1 AutoFocus Completed (Profile No 6)
01:36:35	Target Completed	Target completed (6/11, GCVS CY Lyr)
01:36:37	Target Started (7/11)	Target started (7/11, GCVS S Cyg)
01:39:48	Focusing Started-Foc1	Foc1 Focusing Started (TCF-S)
01:43:48	Focusing Completed	Foc1 AutoFocus Completed (Profile No 7)
01:53:34	Target Completed	Target completed (7/11, GCVS S Cyg)
01:53:37	Target Started (8/11)	Target started (8/11, UGC 10297)
02:17:23	Target Completed	Target completed (8/11, UGC 10297)
02:17:26	Target Started (9/11)	Target started (9/11, GCVS U Her)
02:20:17	Focusing Started-Foc1	Foc1 Focusing Started (TCF-S)
02:23:45	Focusing Completed	Foc1 AutoFocus Completed (Profile No 8)
02:29:08	Target Completed	Target partially completed (9/11, GCVS U Her)
02:29:10	Target Started (10/11)	Target started (10/11, GCVS SS Her)
02:32:37	Focusing Started-Foc1	Foc1 Focusing Started (TCF-S)
02:35:28	Focusing Completed	Foc1 AutoFocus Completed (Profile No 9)
02:37:50	Target Completed	Target partially completed (10/11, GCVS SS Her)
02:37:53	Target Started (11/11)	Target started (11/11, HIP 87937)
02:40:45	Focusing Started-Foc1	Foc1 Focusing Started (TCF-S)
02:43:48	Focusing Completed	Foc1 AutoFocus Completed (Profile No 10)
02:46:32	Target Completed	Target completed (11/11, HIP 87937)
02:46:35	Queue Completed	Job Queue completed
02:46:38	Session Closing	Session closing
02:47:25	Shutter Closed	Shutter closed (closing time 45s)
02:48:08	Dome Parked	Dome parked (parking time 43s)
02:49:02	Telescope Parked	Telescope parked (parking time 49s)
02:49:32	Scope Switched Off	Telescope Power has been switched off via UPB Powerbox.
02:50:22	Services Stopped	Night Services stopped
02:50:24	Session Housekeeping	Housekeeping Started (Cleanup FITS, Create Fits Summary, Transfer Files)
02:50:33	Session Finished	Session Finished

Session Alerts

Time		Alert	Detail
--		No Alerts	--

Operational Issues (2020-05-24, S784)

Critical Issues (0)
Major Issues (0)
Minor Issues (14)
Continuous Improvement (8)

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Critical Issues

None

Major Issues

None

Minor Issues

1st Foc1 focus profile attempt (Near Zenith Focus Field 15), failed with the message "Arithmetric operation result in an underflow. The problem occured whilst reviewing results of 1s test frame. The normal message element (Examining Star...) was missing
| Image                     | Result    | DRO   | FWHM | HFD   | Temp | Max   | Mag    | SN  | Elong |
| Taking 1s box (C) ...       Ok        |  2485 | -99.0 |  0.00 |  9.5 |   283 | -99.00 | -99 | -99.00 |
Failed    Arithmetic operation resulted in an overflow.
Fixed 2020-05-25 (AstroMain 3.23.2)
Focus Profile 3 (Foc1, NGC 5609) was produced but was blank of any data points. Reviewing the report file show first 9 profile points had valid measurements, however after 3 further failed points (after point 12/14), the profile was aborted as star had been deemed to be lost. Data should still have been plotted.
Fixed 2020-05-25 (AstroMain 3.23.2)
Both Foc2 focusing attempts (V3 method) failed as Focus Star couldn't be found in Locate Frames . fSrc inventory file was devoid of any star and examining the image shows it to be devoid of any sufficiently bright / sufficiently sharp focus star. This is a combination of passing cloud (probably ruled out from AllSky Image and starting focus being too far out of focus ? Although target was fairly high in sky it doesn't seem to be so high that roof would have occuluded the guidescope's view of the sky. Guiding during the session was compromised. Need a way of inserting a search for rough focus into the run stream in this situation (either manually or automatically?). At present the Job Queue/Automated Run would either need to be aborted to get to manual mode or speculative Foc2 focusing tweaks made on the fly whilst guiding on a target. Closed out after review on 2021-05-26 (issue didn't totally prevent guiding in session, wide focusing is now available as a Foc2 focusing option).
Closed following later review 2021-05-26 (AstroMain/Session)
Issues with using new Rolling Average Tube Temperature for focusing. BestFocusChart shows discrepency between Best Focus Measurements and Model best focus curve (incorrect temperature parameter has been used). FocusTempChart show Focus Temperature points plotting on UPB Env Temp curve rather than the OTA Temperature curve. Fixed bug in AnalyseFocus Image which had the incorrect assignment FocTemperature = objFocuser2.Temperature ' this is now changed to FocTemperature = Focuser1.Temperature (this is MonitorFoc1AvTemperature, or if null it is objFocuser1.Temperature)
Fixed 2020-05-25 (AstroMain 3.23.2)
Number of Close Shutter Requests still showing as zero in Summary tabulation created at end of session. This is a long outstanding issue which hasn't be resolved. Fixed in Dome.CloseShutter but need to monitor for any double counting or other side effects.
Fixed 2020-05-25 (AstroMain 3.23.2)
Park Dome reporting during shutdown isn't correctly coordinated.
  Park Dome
  Slew Dome to Az 90 ...
  Turn off Dome Slaving...    Ok        Dome Slaving is OFF
Ok        Dome moved to Az 90 deg (Park Position)
Fixed 2020-05-25 (AstroMain 3.23.2)
Text for 'Pressure' in Review Focus Profile section isn't correctly indented. Require AddComment(Tab2+ Tab2 + "Pressure")
Fixed 2020-05-25 (AstroMain 3.23.2)
Faint Galaxy Targets (with minimum sun depression constraints of 12 degs) where placed in the Observing Plan on a night when the sun altiitude didn't reach -12degs for the entire night. e.g. UGCA 317 (C2 constraint) was acquired with sun altitude of -10.6°, PGC 49584 (C1 constraint) was acquired with sun altitude of -11.2°. It is not believed that the relax solar depression constraints option was manually checked, but this might be a starting point to examine in case its is checked via code. Daytime testing of 'AutoBuild' Schedule confirms that relaxation of solar depression constraints is indeed happening for Night Dates in late May (checkbox is seen to become checked by the code when the routine is initiated). Examining ScheduleBuilder's code shows that Solar Depression is relaxed when Duration12.TotalHours (i.e. Total Hours that sun is below -12° altitude) is less than 4. As the spring progresses the number of hours than sun is below -12 deg decreases and the proportion of the plan with sun altitude above -12° altitudes increases, to the point that whole night has sun above -12° altitude and the issue is highlighted. With Duration12.TotalHours = 0, starting sun altitude for plan is reduced down -9° which highlights the issue even further. Whilst some reduction in constraints is appopriate in summer months (if any deep sky summer targets are to be imaged at all), it is still appropriate to try to image such targets in the extreme middle of the night when the sky is as dark as it can be. Prehaps constraints should only be relaxed by 1 or 2 and not at all for C1 targets ? Issue fixed by relaxing the Solar Depression by only 1° for C1/P1 constrained targets and by only 1.6° for C2/P2 & T constrained targets.
Fixed 2020-05-25 (AstroPlan 1.15.2)
First 'Notify ShCap Session' after starting SharpCap Client service comes back as Fail (AstroShpCap is not responding). This is probably becomes the Server has fully had time to open and take requests when the notification request is sent. Some delay should probably be added or some otherway of delaying the notification request until after the main services have started.
Fixed 2020-05-25 (AstroMain 3.23.2)
Dew Heaters were arguably running too hot during the session (taking the Tube Temperatures to 2.5 degC above outside ambient temperature and 1.5degC above UPB temperature. With Humidity at 90-97%, the dew heater power is set to 90-97%, but looking by looking at DDP and Temperatures the dew heater power should be dropped to reduce the convection currents in the tube that could be affecting image quality Some form of feedback loop appears to be required. Add continuous improvement ticket to add a temperature related feedback loop for dew heater.
Closed pending completion of an associated continuous improvement item (AstroMain)
With installation of UPB v1.6 firmware the AstroMain workaround to correct Humidity values needs to be rolled back (2020-05-26). AstroMain (3.23.2 and older) previously fixed UPB readings of 90% to 98% if it was established from previous history or it was likely that a 90% value from UPB was one had dropped down from a real sensor reading of 98/99%. With this issue now fixed with v1.6 firmware update, the workaound needs to be rolled back in order to prevent AstroMain from generating false values of 98% when it has no RH history and its first value from UPB happens to be a real 90% reading. A similar fix will be made to AstroWeather in due course (after current 5 day slot of data has been through it graphing system)
Fixed 2020-05-26 (AstroMain 3.23.3)
New version of AstroWeather not reading Cloud Sensor Relay Flags from 'clarity_2.dat' . AstroWeather 1.9.8 was intended to read relays flags from the small clarity_2.dat file written by CloudSensor III every 5s or so, however it seems to be encountering a file with a csv format, instead of fixed field format file. Problem was due the new routine pointing to the incorrect file when running on AllSky/Weather computer compared to the Development Computer.
Fixed 2020-05-27 (AstroWeather 1.9.9)
Outside Dew Point curve is frequently missing from right hand part of Dew Point Graph (Graph 11). Curve is frequently missing even though Outside Temperature and Outside Humidity have curves (and thus data) over the same range.
Fixed 2020-05-30 (AstroWeather 1.10.1)
Current AllSky Meas at end of Target is given as 'Unknown' (-15, -63 etc). Should the description be 'Clear'. 'CloudValue' is set by AstroAllSky and is set to -1 'Unknown' because the CloudAduRate (-15, -63 etc) could be associated with either extra dark starlit sky or a non-reflecting cloud that is darker than the twilight sky background. The description 'Unknown' is probably correct. Should extra data be used to raise probability that the sky is clear at the sky location being queried.
Closed (AstroMain/AstroAllSky)

Continuous Improvement

The continuation message when an AddComment/ReportComment association is broken is unnecessary. The message
'.. continued below .. (see **)' is too long / necessary. Message has been changed to 'See ** below'
(update: the message is shorterned to just ** in AstroMain 3.24.5)
Done 2020-05-25 (AstroMain 3.23.2)
Image FWHM points should be plotted as small crosses on Zenith FWHM Chart instead of small cyan circles.
Done 2020-05-25 (AstroMain 3.23.2)
Remove generation and output of Session.ObsManager.png picture. This early prototyping picture for the website is not used in the final version of the current session webpage and is redundant. Any useful code from original routibe already forms part of other graph/picture classes.
Done 2020-05-25 (AstroMain 3.23.2)
Show Cloud Sensor Data on AstroGuard program (Clarity, Rain, Light & Relay Flags). Include data that is now available via AstroWeather 1.10 (port 4011)
Done 2020-05-28 (AstroGuard 1.3)
Show Cloud Sensor Safety Data & Relay Flags on Manager Tab & Obs.Viewer. Include relay data that is now available via AstroWeather 1.10.
Done 2020-05-28 (AstroMain 3.24)
Add a temperature related feedback loop for finer control of Dew Heater to restrict how high the telescope tube temperatures can rise above ambient temperature.
Done 2020-06-06 (AstroMain 3.25)
Utility targets (Near Zenith Focus, Park, Mapping) should be drawn with square symbols on Slewing Charts instead of circle symbols associated with Observation Targets.
To do (AstroMain)
Look into using modelled sky brightness as a Target Observation Constraint for Schedule Building. AstroAllSky has a algorithm for accurately calculating sky brightness taking into account sun altitude (solar depression) and moon altitude/phase, this model brightness could be used for selection target observations for Schedule Building. This would require additional columns in Constraints Tables/Constraints Form, and changes to the Target Filtering code, but it could be a way of very finely finessing the conditions. Could even be used during operations to ensure that actual sky brightness was not greater than constraint.
To consider (AstroPlan)

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2019-05-25

Pegasus UPB - v1.6.0

A new version of UPB Software (v 1.6.0) was sent to be me today by Pegasus Astro (May 2020) for earlier testing. The new version is not yet released on Pegasus Astro Website but should be shortly. The new version was successfully installed onto Development Computer and Observatory Computer (2020-05-25) and new v1.6 firmware loaded on to the UPB Box. Changes in v.1.6.0 according to its change log are:

* UI: Fix graph exception when value is not numeric
* Feature: Display uptime (firmware v1.6)
* Bug: Display power on boot settings

Changes in v1.6 firmware include
- Better memory handling of parallel task processing
- New Stepper Backlash Algorth
- Stepper Motor Control rewrite to use less memory
- Fix issue that relative humidity was dropped from 99% -> 90%

Humidity Values
The first night of operation using new firmware showed that the problem with humidity readings had been fixed.

AstroSuite workarounds to handle the earlier '99->90% dropped down values will now be removed to prevent issues where 90% humidity values at start up of AstroMain or AstroWeather aren't wrongly 'corrected' to 98% (99%)

Memory
16,200 k Initial Memory (not connected to physical box)
83,800 k Memory used after 15 hours :

[ Pegasus Astro Support Page: https://pegasusastro.com/support/ ]

TCF-S - Focus Temperature Compensation (12" LX200)

After a review of best focus vs temperature data from recent session it is apparent that the temperature compensation gradient currently used (-133.6 steps/°C) is too agressive and needs to reduced. A new gradient of -100 steps/°C is proposed for use in the next session onwards. This will be used with a datum focus position of 3300 steps at 0°C and an initial focus correction offset of 0 steps.

The following graphs demonstrate reasonable fit between the proposed new gradient of -100 steps/°C with best focus data from 4 recent sessions.

Note that on any single night there is often quite a scatter in best focus for a given temperature. It is postulated that this is due to a combination of differences in airmass, atmosphere properties and possible primary mirror slop.

Note that there is quite a range on focus offset between session which is postulated to be due to variation in atmospheric properties (temperature, pressure) between sessions. There is however some suspicion that there might be a very gradual slippage in the primary mirror over time (e.g. the focus position at 0°C datum varies between 4100 in S765 (2020-04-01) to 3150 in S784 (2020-05-24). However this might be due to seasonal changes in the atmosphere.

Best Focus vs Temperature Graphs for 4 recent sessions
showing good fit between data and new proposed Temperature Coefficient of -100°C
S765 ( 2020-04-01), S779 (2020-05-05), S780 (2020-05-06), S784 (2020-05-24)

Comparison of Safe/Unsafe Conditions & Criteria

As part of implementing more maintainable safety code including addition of new criteria a comparison was made of the safety critera used in the Observatory.

MUST CLOSE (True if any of these are true)
	Cloud Sensor Relay State Safe/Unsafe	AstroMain Obs.Manager Function MustClose(reason)	AstroAllSky Synopsis State MustClose

Rain	> 1	> 0.3 (plus Trim)
Clarity	< 20	< 20
Light	> 20 (unless disabled)	> 20 (unless disabled)

Sun Altitude		> -2 (unless disabled)
Wind		> 20
Outside Humidity		> 97
Outside Temperature		< -12

Others		Synopsis.CriticalRain = Critical
		Synopsis.CriticalRainThreat = Critical
		Synopsis.CriticalCloud = Critical
		Synopsis.CriticalWind = Critical

		Minutes Since Last CloudSensor Data > DataToleranceMinutes (5, 20, 45, 180)

CAN OPEN (Only true if all criteria are true)
	Cloud Sensor Relay	AstroMain Obs.Manager Function CanOpen(reason_can't)	AstroAllSky Synopsis State CanOpenWithCaution	AstroGuard

Rain	not used, but dome	< 0.3 (plus trim)
Clarity	will close after	>= 24
Light	30s if Unsafe	< 20 (unless disabled)

Wind		< 15
Outside Humidity		<= 97
Outside Temperature		> -10

Others		Synopsis.CriticalRain <> Critical
		Synopsis.CriticalRainThreat <> Critical / Warning
		Synopsis.CriticalCloud <> Critical
		Synopsis.CriticalWind <> Critical

		Minutes Since Last CloudSensor Data < 3
		Minutes Since Last Synopsis Data < 3
		Minutes Since Last Rain > 10



Traffic Lights	AstroMain Manager Tab	AstroMain Obs.Viewer	AstroAllSky Synopsis	AstroGuard Manager Tab	AstroGuard

Rain	< 0.1 + RainTrim 0.1 to 0.3+ RainTrim > 0.3 + RainTrim	Synopsis.Rain = Normal Synopsis.Rain = Warning or Synopsis.RainThreat = Warning Synopsis.Rain = Critical or Synopsis.RainThreat = Critical	< 0.1 + RainTrim (=Normal) 0.1 to 0.3+ RainTrim (=Warning) > 0.3 + RainTrim (=Critical) or vcNull and (Stars<=4 or RainThreat=Critical)	< 0.1 .1 to .3 > 0.3	Synopsis.Rain = Normal Synopsis.Rain = Warning or Synopsis.RainThreat = Warning Synopsis.Rain = Critical or Synopsis.RainThreat = Critical

Rain Threat			Cases not covered below (=Normal) precipNext15MinProb > 0.1 Or (ER.precipNext15MinProb > 0.1 And precipNext15MinIntensity > 0.2 ) (=Warning) (precipNext15MinProb > 0.5 Or (precipNext15MinProb > 0.2 And precipNext15MinIntensity > 0.2)) And (Clarity = vcNull Or Clarity < 30) (=Critical)

Clarity	>32 25 to 32 20 to 24 < 20	Synopsis.Cloud = Normal Synopsis.Cloud = Warning Synopsis.Cloud = Critical	>28 (=Normal) 20 to 28 (=Warning) < 20 or (vcNull and Stars<5) (=Critical)	>32 25 to 32 20 to 24 < 20	Synopsis.Cloud = Normal Synopsis.Cloud = Warning Synopsis.Cloud = Critical

Light	< 5 5 to 15 16 to 28 > 28	Synopsis.Light = Normal Synopsis.Light = Warning Synopsis.Light = Critical	<15 (=Normal) 15 to 28 or SunAlt 0 to -2 or ZenithAduRate > 100000 (=Warning) > 28 or (SunAlt > 0) or (vcNull and SunAlt >-2 (=Critical)	< 5 5 to 15 16 to 28 > 28	Synopsis.Light = Normal Synopsis.Light = Warning Synopsis.Light = Critical

Stars	> 20 9 to 20 3 to 8 < 3	> 20 9 to 20 3 to 8 < 3		> 20 9 to 20 3 to 8 < 3

Wind	0 to 10 10 to 20 > 20	Synopsis.Wind = Normal Synopsis.Wind = Warning Synopsis.Wind = Critical	0 to 10 (=Normal) 10 to 20 (=Warning) > 20 (=Critical)	not displayed	Synopsis.Wind = Normal Synopsis.Wind = Warning Synopsis.Wind = Critical

Outdoor Temperature	> 0 0 to -5 -5 to -10 -10 to -12 < -12	> 0 0 to -5 -5 to -12 < -12		not displayed

Outdoor Humidity	not displayed	0 to 93 94 to 97 > 97		not displayed

This Web Page:	Notes - Session 784 (2020-05-24)
Last Updated :	2024-02-21
Site Owner :	David Richards
Home Page :	David's Astronomy Web Site