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 __**OBSERVING PROCEDURES**__\\
-[[chara:operating_procedures#labprotocol|Lab Protocol]]\\ [[/Operating%20Procedures#chapter.labprep|Preparations in the Lab Prior to Observing]]\\ [[/Operating%20Procedures#chapter.controlroom|Setting up Computer in the Control Room]]\\ [[/Text%20Commands%20for%20CHARA%20GUIs|Text Commands for CHARA GUIs]]\\ [[/Operating%20Procedures#chapter.observing_conditions|Observing Conditions]]\\ [[/Operating%20Procedures#GoingOnSky|Going on Sky]]\\ [[/Operating%20Procedures#ShuttingDown|Procedure for Shutting Down the Array]]\\ \\ __**SUPPLEMENTAL INFORMATION**__\\ [[/Remote%20Observing|Remote Observing]]\\ [[/Power%20Outage|Power Outage]]\\ [[file/view/Co-Phasing_with_CHARA.pdf/615228791/Co-Phasing_with_CHARA.pdf|Co-phasing with the CHARA phase reference]]\\ [[/file/view/Labao%20with%20Starlight%20v4.pdf/627133425/Labao%20with%20Starlight%20v4.pdf|Using Labao with Starlight]]\\ [[/file/view/S2_New_Finder_Camera-r1.docx/615406377/S2_New_Finder_Camera-r1.docx|New S2 Finder Instructions]]\\ [[/Night-time%20POP%20Changes|Night-time POP Changes]]\\ __[[/Azimuth%20coud%C3%A9%20alignments|Azimuth coudé alignments]]__\\ [[/file/view/Tiptilt%20Splitters%20Change.pdf/368145106/Tiptilt%20Splitters%20Change.pdf|Tip-tilt Splitters Change]]\\ [[/Trouble%20Shooting|Trouble Shooting]]\\ [[/horizons|Telescope Horizon Limits]]\\ [[/Restarting%20Servers|Restarting Servers]]\\ \\ __**INSTRUMENTS**__\\ [[/Instruments|Instrument Manuals]]\\ [[/Instruments|Observing Logs]]\\ [[/FringeOffsets|Recent fringe offsets]]\\ [[/Instruments|Software setup for specific instruments]]\\ [[/Classic%20Faint%20Object%20Procedures|Classic Faint Object Procedures]]\\ \\ __**DOCUMENTATION TO BE UPDATED**__\\  Note: the information contained in these wiki pages needs to be incorporated into the documentation in the CVS tree.\\ \\ CHARA Array Operating Procedures\\  Copyright © 2005-2018 The CHARA Team\\  Last updated: 2018-01-11\\ \\ \\ \\ {{/file/view/Picture_21.png/308555522/247x275/Picture_21.png|Picture_21.png}}\\ \\ \\ {{/file/view/Picture_22.png/308555456/800x304/Picture_22.png|Picture_22.png}}\\ \\ \\ \\ \\ _\\ \\ \\ **Chapter 1: **\\ ** LAB PROTOCOL**\\ \\ {{/file/view/Picture_28.png/213864986/80x125/Picture_28.png|Picture_28.png}}{{/file/view/Picture_29.png/213865030/149x54/Picture_29.png|Picture_29.png}}\\ \\ __1.1 Lab Rules Intro__\\ \\  The CHARA optics lab is a building within a building and is intended to provide thermal and vibrational stability. The main goal of the CHARA lab rules is to keep all optics and equipment safe from any hazards. The crucial issue being misalignment of anything. The amount of dust and dander must be kept to a minimum.\\ \\ __ 1.2 The Metrology Laser__\\ \\  A high-powered infrared laser is used for the delay line metrology. This is an eye hazard, so before entering the lab check to make sure the red light above the door is not on. If the laser is activated, it is a must to put on IR-protective goggles. If you are not sure, wear the goggles.\\ \\ __ 1.3 General Lab Rules__\\ \\ Please remember that:\\  Procedures in the lab must be followed closely and failure to follow these rules will result in loss of lab privileges.\\ \\  • Before entering the lab, you must have a reason or tasks at hand.\\  • Lab booties/shoe covers must be worn by all. Throw out booties that have holes in them. The traction tape on the steps are particularly rough on booties so examine them before and after using them.\\  • Proper clothing is also important. Loose hanging jackets or garments can snag on mirrors or other exposed equipment and are better left outside of the lab until you are ﬁnished.\\  • Please be alert and move slowly and cautiously.\\  • When entering the lab make sure to walk across the sticky ﬂoor mat. If the mat isn’t sticky, remove the top layer. If this is close to the ﬁnal layer please notify the staff.\\  • No more than three people are allowed in the lab at once unless it is 3 to 4 hours before observing time or there is some pressing need. Many bodies can create unwanted atmospheric eﬀects. Besides, with too many people, it is too easy to bump into each other and the equipment.\\  • If you bump, hit, move or just tap anything in the slightest way, let us know.\\  • Never touch anything you have not been trained to use. If ever in any doubt, leave it alone and get someone who knows.\\  • Any unusual sounds, sights, movement of equipment, etc., should be noted.\\  • You must know the path of the laser beams, metrology or alignment. Stay out of their way especially right before observing. If you must go into the lab during this time don’t forget to put on IR-protective goggles.\\  • Access and use of the lab requires training. If a piece of equipment does not appear to be operating properly let us know immediately. Also if you are uncertain about a lab procedure or a step in the alignment sequence contact us before proceeding.\\ • When leaving the lab any time of the day, remember to turn off all lights (fluorescent and incandescent). Lights left on generate unnecessary heat in the lab.\\ \\ [[/Operating%20Procedures|Back to Main Menu]]\\ \\ \\ **Chapter 2: **Version 2. August 27, 2012 by Judit, Version 3 January 2015 by Norm, Version ? October 2017 by Norm\\ **PREPARATIONS ****IN THE LAB ****PRIOR TO OBSERVING**\\ \\ These are routine tasks to be performed in and around the lab every evening to prepare the array for regular observations.\\ \\ __2.1 Starting the vacuum pump for the light pipes__\\ Go into vacuum pump shack\\
+[[chara:operating_procedures#lab_protocol|Lab Protocol]]\\
+[[chara:operating_procedures#preparations_in_the_lab_prior_to_observing|Preparations in the Lab Prior to Observing]]\\
+[[chara:operating_procedures#setting_up_computer_in_the_control_room|Setting up Computer in the Control Room]]\\
+[[chara:text_commands_for_chara_guis|Text Commands for CHARA GUIs]]\\
+[[chara:operating_procedures#observing_conditions|Observing Conditions]]\\
+[[/Operating%20Procedures#GoingOnSky|Going on Sky]]\\
+[[/Operating%20Procedures#ShuttingDown|Procedure for Shutting Down the Array]]\\
+\\
+__**SUPPLEMENTAL INFORMATION**__\\
+[[/Remote%20Observing|Remote Observing]]\\
+[[/Power%20Outage|Power Outage]]\\
+[[file/view/Co-Phasing_with_CHARA.pdf/615228791/Co-Phasing_with_CHARA.pdf|Co-phasing with the CHARA phase reference]]\\
+[[/file/view/Labao%20with%20Starlight%20v4.pdf/627133425/Labao%20with%20Starlight%20v4.pdf|Using Labao with Starlight]]\\
+[[/file/view/S2_New_Finder_Camera-r1.docx/615406377/S2_New_Finder_Camera-r1.docx|New S2 Finder Instructions]]\\
+[[/Night-time%20POP%20Changes|Night-time POP Changes]]\\
+__[[/Azimuth%20coud%C3%A9%20alignments|Azimuth coudé alignments]]__\\
+[[/file/view/Tiptilt%20Splitters%20Change.pdf/368145106/Tiptilt%20Splitters%20Change.pdf|Tip-tilt Splitters Change]]\\
+[[/Trouble%20Shooting|Trouble Shooting]]\\
+[[/horizons|Telescope Horizon Limits]]\\
+[[/Restarting%20Servers|Restarting Servers]]\\
+\\
+__**INSTRUMENTS**__\\
+[[/Instruments|Instrument Manuals]]\\
+[[/Instruments|Observing Logs]]\\
+[[/FringeOffsets|Recent fringe offsets]]\\
+[[/Instruments|Software setup for specific instruments]]\\
+[[/Classic%20Faint%20Object%20Procedures|Classic Faint Object Procedures]]\\
+\\
+__**DOCUMENTATION TO BE UPDATED**__\\
+Note: the information contained in these wiki pages needs to be incorporated into the documentation in the CVS tree.\\
+\\
+CHARA Array Operating Procedures\\
+Copyright © 2005-2018 The CHARA Team\\
+Last updated: 2018-01-11\\
+\\
+\\
+\\
+{{/file/view/Picture_21.png/308555522/247x275/Picture_21.png|Picture_21.png}}\\
+\\
+\\
+{{/file/view/Picture_22.png/308555456/800x304/Picture_22.png|Picture_22.png}}\\
+\\
+\\
+\\
+\\
+_\\
+\\
+\\
+====Lab Protocol====
+\\ \\ {{/file/view/Picture_28.png/213864986/80x125/Picture_28.png|Picture_28.png}}{{/file/view/Picture_29.png/213865030/149x54/Picture_29.png|Picture_29.png}}\\ \\ __1.1 Lab Rules Intro__\\ \\  The CHARA optics lab is a building within a building and is intended to provide thermal and vibrational stability. The main goal of the CHARA lab rules is to keep all optics and equipment safe from any hazards. The crucial issue being misalignment of anything. The amount of dust and dander must be kept to a minimum.\\ \\ __ 1.2 The Metrology Laser__\\ \\  A high-powered infrared laser is used for the delay line metrology. This is an eye hazard, so before entering the lab check to make sure the red light above the door is not on. If the laser is activated, it is a must to put on IR-protective goggles. If you are not sure, wear the goggles.\\ \\ __ 1.3 General Lab Rules__\\ \\ Please remember that:\\  Procedures in the lab must be followed closely and failure to follow these rules will result in loss of lab privileges.\\ \\  • Before entering the lab, you must have a reason or tasks at hand.\\  • Lab booties/shoe covers must be worn by all. Throw out booties that have holes in them. The traction tape on the steps are particularly rough on booties so examine them before and after using them.\\  • Proper clothing is also important. Loose hanging jackets or garments can snag on mirrors or other exposed equipment and are better left outside of the lab until you are ﬁnished.\\  • Please be alert and move slowly and cautiously.\\  • When entering the lab make sure to walk across the sticky ﬂoor mat. If the mat isn’t sticky, remove the top layer. If this is close to the ﬁnal layer please notify the staff.\\  • No more than three people are allowed in the lab at once unless it is 3 to 4 hours before observing time or there is some pressing need. Many bodies can create unwanted atmospheric eﬀects. Besides, with too many people, it is too easy to bump into each other and the equipment.\\  • If you bump, hit, move or just tap anything in the slightest way, let us know.\\  • Never touch anything you have not been trained to use. If ever in any doubt, leave it alone and get someone who knows.\\  • Any unusual sounds, sights, movement of equipment, etc., should be noted.\\  • You must know the path of the laser beams, metrology or alignment. Stay out of their way especially right before observing. If you must go into the lab during this time don’t forget to put on IR-protective goggles.\\  • Access and use of the lab requires training. If a piece of equipment does not appear to be operating properly let us know immediately. Also if you are uncertain about a lab procedure or a step in the alignment sequence contact us before proceeding.\\ • When leaving the lab any time of the day, remember to turn off all lights (fluorescent and incandescent). Lights left on generate unnecessary heat in the lab.\\ \\ [[/Operating%20Procedures|Back to Main Menu]]\\ \\ \\ **Chapter 2: **Version 2. August 27, 2012 by Judit, Version 3 January 2015 by Norm, Version ? October 2017 by Norm\\
+====Preparations in the Lab Prior to Observing====
+ \\ \\ These are routine tasks to be performed in and around the lab every evening to prepare the array for regular observations.\\ \\ __2.1 Starting the vacuum pump for the light pipes__\\ Go into vacuum pump shack\\
   * flip on power switch for pump (wait for blower to go on)
@@ Line 88: / Line 140: @@
   * If using CLASSIC or CLIMB, turn on the black box above the NIRO computer, and then turn on the silver box below it on the same cart.
   * After lab is completely setup, you need to take off tiptilt cover, but do so with only the dim lights on and the laser shutter closed >> you don't want to blast CCD with light.
-\\ [[/Operating%20Procedures|Back To Main Menu]]\\ \\ \\ **Chapter 3:** (edited 2012Aug29 by Gail and Chris)\\ **SETTING UP COMPUTER IN THE CONTROL ROOM PRIOR TO OBSERVING**\\ \\ __3.1 General Overview of Computer Setup__\\
+\\ [[/Operating%20Procedures|Back To Main Menu]]\\ \\ \\ **Chapter 3:** (edited 2012Aug29 by Gail and Chris)\\
+====Setting up Computer in the Control Room====
+ \\ \\ __3.1 General Overview of Computer Setup__\\
   * There are six computer screens which are now horizontally arrayed.
@@ Line 193: / Line 248: @@
   * Metrology Laser and Metrology Monitor
   * Pico 2
-\\  3.10 See the instruments page for information about starting different instruments at the beginning of the night:\\ [[/Instruments|Instruments: CLASSIC, CLIMB, MIRC, PAVO, VEGA, FLUOR]]\\ \\ [[/Operating%20Procedures|Back to Main Menu]]\\ \\ \\ **Chapter 4: **\\ **OBSERVING CONDITIONS**\\ \\ [[http://www.wrh.noaa.gov/lox/scripts/getprodplus.php?wfo=lox&prod=054ZFPLOX&pretty=yes|{{file/view/Picture_4.png/260449330/463x72/Picture_4.png|Picture_4.png}}]]\\ \\ \\ __ 4.1 Observing Conditions Intro__\\ \\  In opening the CHARA Array, conditions should be, for the most part, ideal. If the weather is questionable, it is best if the sky is 60% to 70% clear and conditions stable before commencing. Delicate optics and electronics make up the majority of the Array and it’s better to err on the side of caution. In preparation for observing, the Mount Wilson weather server and web-based weather pages should be consulted. The telescopes can now be closed in about 10 minutes from the control room. With this in mind, don’t open up the telescopes to observe if conditions can change for the worse rapidly enough that you don’t get 10 minutes or more to close down safely. Weather stations now exist at each bunker and there is a control system software application to display the current conditions. Soon this application will also issue warnings. One can also use the white Radio Shack thermometer/hygrometer outside of the control room. With the Array becoming more fancily automated and weather monitoring technology becoming more robust (weather servers, satellite images, web cams, etc.), almost all weather monitoring can be done seemingly without ever leaving the cozy control room. Unfortunately this is not a good policy and nothing beats going outside for a gander and giving the sky a good old fashioned assessment. Obviously weather variations do exist from telescope to telescope, as much as 16% in RH at times. Most of the time this just means something is blowing through and opening is not a good idea. These circumstances need to be dealt with cautiously depending on the given weather conditions. Allowing extra time to close is advised in case of any problems. If any questions or doubts arise contact one of the CHARA staﬀ.\\ \\ __ 4.2 Humidity__\\ \\ Only open the telescopes if the humidity is steady or dropping, at 75% or below. If the roofs outside the control room are ever dripping, then the telescopes should not be opened or should be closed immediately. If when starting out, the RH is above 80%, do not open unless it drops to below 75% and stays there for at least 30 minutes. If you do open after that, be wary and watch the RH, and if it starts rising, be prepared to close. Closing up takes about 10 minutes, so be ready for that. The array operator is in charge of protecting the telescopes and makes the final decision on whether the conditions are safe to open. If the RH is low at the beginning of the night, and rises after you are already open, the array operator should inform the PI around 70-75%, and start closing between 80-85%. Other humidity warning signs are: 1) water dripping oﬀ the OPLE building (or wet spots on the asphalt straight down from the eaves); 2) cold, clammy feel to metal objects such as railings; and 3) dew forming on the parked cars. It is important to note that the humidity can rise from 50% to 80% in as little as 10 minutes, so please keep a close eye on the rate of change of the humidity plots. It can also rain from passing clouds when the humidity is quite low, even 50% RH or lower. If in doubt, stay closed.\\ \\ __ 4.3 Dust__\\ \\  Gauging the airborne dust is problematic because you need a bright light and a relatively dark night. In general, you want to look in the bottom 0.5 meter of the light column. There will be a diﬀuse column lit up by the beam – don’t worry about it, just follow the dust glints. If you can count the dust glints, the conditions are safe to observe. If it looks like a blizzard, close up. If any of the dust glints shine with an orange or a peach hue, or the dust glints look abnormally large, the dust is probably ash – close up immediately. Ash seriously degrades bare aluminum coatings. Dust and wind go together. But, just because it is calm, the dust conditions might still be bad. If it was windy a few days earlier, it could have kicked up a lot of dust, which can take several days to settle. Finally, during late spring to early summer, conifer tree pollen can be problematic. If particulates are borderline please email the CHARA day staﬀ so they can clean the optics as soon as possible.\\ \\ __ 4.4 Wind__\\ \\  Wind has the eﬀect of degrading the seeing as well as kicking up dust. The wind eﬀects are ampliﬁed in the tunnel between the OPLE building and the oﬃce building, so look for other places to gauge the wind conditions. The intersection of the road and the trail to the eastern telescopes is a good place to gauge conditions. To be on the safe side, we only observe under calm to light breeze conditions (gusts less than about 10 knots, or 15 kph). Windy conditions we try to avoid. If you can hear the gusts from your desk, it is too windy to observe. If you hear whistling from the light pipe supports, it is too windy to observe. If you hear the signs on the chain banging, it is too windy to observe. Occasionally you will hear the wind rustling the tops of the tall trees, but it is calm at ground level. This is a symptom of chaotic wind conditions, and almost always happens during windy episodes (Santa Anas, onshore ﬂows, etc.), during which you shouldn’t observe – the seeing will be bad anyway. Be cautious about opening if wind gusts are above 15-20 kph; winds this high are usually correlated with bad seeing and poor data quality. Telescopes and domes should be closed if the wind gusts get up to 30 kph. This will protect the optics from branches and debris that can be blown in from the surrounding trees.\\ \\ __ 4.5 Snow__\\  Because of the nature of the snow that falls on Mount Wilson, it is usually not a problem. If snow/wind conditions are such that drifting occurs, don’t open up. If there is still any snow stuck to the telescope dome itself, don’t open up. If there is snow still on the trees and branches procede with caution and make a visual assessment. Otherwise, you are free to observe (assuming the humidity, dust, and wind conditions allow it).\\ \\ __ 4.6 Essential Observing Links__\\ \\  • 150-Foot Solar Tower Current TowerCam Image ([[http://www.astro.ucla.edu/%7Eobs/towercam.htm|http://www.astro.ucla.edu/~obs/towercam.htm]]) a live view of the mountain. Check the clock when viewing the page as it can sometimes fail to refresh.\\  Caltech Millikan Library Camera (http://library.caltech.edu/milcam/) A view of Mt. Wilson from the south, good for watching low clouds and fog that cling to the mountain.\\ • National Weather Service ([[http://forecast.weather.gov/MapClick.php?site=lox&textField1=34.2231&textField2=-118.0587&smap=1#.VKsuq2TF8rO|http://forecast.weather.gov]]) Mount Wilson weather and 5 day forecast\\  CHARA Array weather ([[http://www.astro.gsu.edu/~theo/Dropbox/Weather%20Site/wxlocal.html|http://www.astro.gsu.edu/]]) Centralized weather station for CHARA\\  CHARA telescopes spy cams and weather graph ([[http://www.astro.gsu.edu/~theo/Dropbox/Scopes/chara_scopes.html|http://www.astro.gsu.edu]]) Status of each CHARA telescope\\  Aerospace Corporation weather station ([[http://www.weatherlink.com/user/mocam/index.php?view=summary&headers=1|http://www.weatherlink.com/user/mocam]]) Another local station, always current.\\  Jet stream forecast (http://squall.sfsu.edu/scripts/jetstream_modelsml_fcst.html) Monitors high level winds which degrade seeing\\  IR satellite loop ([[http://www.wrh.noaa.gov/lox/scripts/animate.php?root=sat_4km&list=IR4.GIF.3.jpg,IR4.GIF.4.jpg,IR4.GIF.5.jpg,IR4.GIF.6.jpg,IR4.GIF.7.jpg,IR4.GIF.8.jpg|http://www.wrh.noaa.gov]]) Keeps an eye on storms and clouds coming in\\  • California Regional Weather Server (http://squall.sfsu.edu/) A variety of weather links\\  • Clear Sky Clock (http://cleardarksky.com/c/MtWilsonOBCAkey.html) a forecasting tool, but be aware that the humidity forecast is often incorrect on this site as it incorporates the marine layer forecast for the valley below, which does not affect us 80-90% of the time\\ \\ [[/Operating%20Procedures|Back to Main Menu]]\\ \\ {{/file/view/Picture_6.png/260450460/278x131/Picture_6.png|Picture_6.png}}\\ \\ \\ **Chapter 5:**\\ __**Going on Sky**__\\ \\ __5.1 Opening the Telescope Domes and enclosures__\\ \\  You can begin opening the telescope domes and enclosures about an hour or two before sunset. This will help air out the domes and improve seeing at the start of the night. Hot days benefit from an earlier opening to allow the scopes to cool. Before opening the domes make sure to check the current weather conditions and the forecast to make sure conditions are safe to open and are likely to be stable as you wait for it to get dark. Also confirm that Judit has finished the alignments in the lab as opening the domes will not allow the completion of the M10 alignments. If you do not see her, call the computer room phone number listed on the clipboard on the wall.\\
+\\  3.10 See the instruments page for information about starting different instruments at the beginning of the night:\\ [[/Instruments|Instruments: CLASSIC, CLIMB, MIRC, PAVO, VEGA, FLUOR]]\\ \\ [[/Operating%20Procedures|Back to Main Menu]]\\ \\ \\ **Chapter 4: **\\
+====OBSERVING CONDITIONS====
+\\ \\ [[http://www.wrh.noaa.gov/lox/scripts/getprodplus.php?wfo=lox&prod=054ZFPLOX&pretty=yes|{{file/view/Picture_4.png/260449330/463x72/Picture_4.png|Picture_4.png}}]]\\ \\ \\ __ 4.1 Observing Conditions Intro__\\ \\  In opening the CHARA Array, conditions should be, for the most part, ideal. If the weather is questionable, it is best if the sky is 60% to 70% clear and conditions stable before commencing. Delicate optics and electronics make up the majority of the Array and it’s better to err on the side of caution. In preparation for observing, the Mount Wilson weather server and web-based weather pages should be consulted. The telescopes can now be closed in about 10 minutes from the control room. With this in mind, don’t open up the telescopes to observe if conditions can change for the worse rapidly enough that you don’t get 10 minutes or more to close down safely. Weather stations now exist at each bunker and there is a control system software application to display the current conditions. Soon this application will also issue warnings. One can also use the white Radio Shack thermometer/hygrometer outside of the control room. With the Array becoming more fancily automated and weather monitoring technology becoming more robust (weather servers, satellite images, web cams, etc.), almost all weather monitoring can be done seemingly without ever leaving the cozy control room. Unfortunately this is not a good policy and nothing beats going outside for a gander and giving the sky a good old fashioned assessment. Obviously weather variations do exist from telescope to telescope, as much as 16% in RH at times. Most of the time this just means something is blowing through and opening is not a good idea. These circumstances need to be dealt with cautiously depending on the given weather conditions. Allowing extra time to close is advised in case of any problems. If any questions or doubts arise contact one of the CHARA staﬀ.\\ \\ __ 4.2 Humidity__\\ \\ Only open the telescopes if the humidity is steady or dropping, at 75% or below. If the roofs outside the control room are ever dripping, then the telescopes should not be opened or should be closed immediately. If when starting out, the RH is above 80%, do not open unless it drops to below 75% and stays there for at least 30 minutes. If you do open after that, be wary and watch the RH, and if it starts rising, be prepared to close. Closing up takes about 10 minutes, so be ready for that. The array operator is in charge of protecting the telescopes and makes the final decision on whether the conditions are safe to open. If the RH is low at the beginning of the night, and rises after you are already open, the array operator should inform the PI around 70-75%, and start closing between 80-85%. Other humidity warning signs are: 1) water dripping oﬀ the OPLE building (or wet spots on the asphalt straight down from the eaves); 2) cold, clammy feel to metal objects such as railings; and 3) dew forming on the parked cars. It is important to note that the humidity can rise from 50% to 80% in as little as 10 minutes, so please keep a close eye on the rate of change of the humidity plots. It can also rain from passing clouds when the humidity is quite low, even 50% RH or lower. If in doubt, stay closed.\\ \\ __ 4.3 Dust__\\ \\  Gauging the airborne dust is problematic because you need a bright light and a relatively dark night. In general, you want to look in the bottom 0.5 meter of the light column. There will be a diﬀuse column lit up by the beam – don’t worry about it, just follow the dust glints. If you can count the dust glints, the conditions are safe to observe. If it looks like a blizzard, close up. If any of the dust glints shine with an orange or a peach hue, or the dust glints look abnormally large, the dust is probably ash – close up immediately. Ash seriously degrades bare aluminum coatings. Dust and wind go together. But, just because it is calm, the dust conditions might still be bad. If it was windy a few days earlier, it could have kicked up a lot of dust, which can take several days to settle. Finally, during late spring to early summer, conifer tree pollen can be problematic. If particulates are borderline please email the CHARA day staﬀ so they can clean the optics as soon as possible.\\ \\ __ 4.4 Wind__\\ \\  Wind has the eﬀect of degrading the seeing as well as kicking up dust. The wind eﬀects are ampliﬁed in the tunnel between the OPLE building and the oﬃce building, so look for other places to gauge the wind conditions. The intersection of the road and the trail to the eastern telescopes is a good place to gauge conditions. To be on the safe side, we only observe under calm to light breeze conditions (gusts less than about 10 knots, or 15 kph). Windy conditions we try to avoid. If you can hear the gusts from your desk, it is too windy to observe. If you hear whistling from the light pipe supports, it is too windy to observe. If you hear the signs on the chain banging, it is too windy to observe. Occasionally you will hear the wind rustling the tops of the tall trees, but it is calm at ground level. This is a symptom of chaotic wind conditions, and almost always happens during windy episodes (Santa Anas, onshore ﬂows, etc.), during which you shouldn’t observe – the seeing will be bad anyway. Be cautious about opening if wind gusts are above 15-20 kph; winds this high are usually correlated with bad seeing and poor data quality. Telescopes and domes should be closed if the wind gusts get up to 30 kph. This will protect the optics from branches and debris that can be blown in from the surrounding trees.\\ \\ __ 4.5 Snow__\\  Because of the nature of the snow that falls on Mount Wilson, it is usually not a problem. If snow/wind conditions are such that drifting occurs, don’t open up. If there is still any snow stuck to the telescope dome itself, don’t open up. If there is snow still on the trees and branches procede with caution and make a visual assessment. Otherwise, you are free to observe (assuming the humidity, dust, and wind conditions allow it).\\ \\ __ 4.6 Essential Observing Links__\\ \\  • 150-Foot Solar Tower Current TowerCam Image ([[http://www.astro.ucla.edu/%7Eobs/towercam.htm|http://www.astro.ucla.edu/~obs/towercam.htm]]) a live view of the mountain. Check the clock when viewing the page as it can sometimes fail to refresh.\\  Caltech Millikan Library Camera (http://library.caltech.edu/milcam/) A view of Mt. Wilson from the south, good for watching low clouds and fog that cling to the mountain.\\ • National Weather Service ([[http://forecast.weather.gov/MapClick.php?site=lox&textField1=34.2231&textField2=-118.0587&smap=1#.VKsuq2TF8rO|http://forecast.weather.gov]]) Mount Wilson weather and 5 day forecast\\  CHARA Array weather ([[http://www.astro.gsu.edu/~theo/Dropbox/Weather%20Site/wxlocal.html|http://www.astro.gsu.edu/]]) Centralized weather station for CHARA\\  CHARA telescopes spy cams and weather graph ([[http://www.astro.gsu.edu/~theo/Dropbox/Scopes/chara_scopes.html|http://www.astro.gsu.edu]]) Status of each CHARA telescope\\  Aerospace Corporation weather station ([[http://www.weatherlink.com/user/mocam/index.php?view=summary&headers=1|http://www.weatherlink.com/user/mocam]]) Another local station, always current.\\  Jet stream forecast (http://squall.sfsu.edu/scripts/jetstream_modelsml_fcst.html) Monitors high level winds which degrade seeing\\  IR satellite loop ([[http://www.wrh.noaa.gov/lox/scripts/animate.php?root=sat_4km&list=IR4.GIF.3.jpg,IR4.GIF.4.jpg,IR4.GIF.5.jpg,IR4.GIF.6.jpg,IR4.GIF.7.jpg,IR4.GIF.8.jpg|http://www.wrh.noaa.gov]]) Keeps an eye on storms and clouds coming in\\  • California Regional Weather Server (http://squall.sfsu.edu/) A variety of weather links\\  • Clear Sky Clock (http://cleardarksky.com/c/MtWilsonOBCAkey.html) a forecasting tool, but be aware that the humidity forecast is often incorrect on this site as it incorporates the marine layer forecast for the valley below, which does not affect us 80-90% of the time\\ \\ [[/Operating%20Procedures|Back to Main Menu]]\\ \\ {{/file/view/Picture_6.png/260450460/278x131/Picture_6.png|Picture_6.png}}\\ \\ \\ **Chapter 5:**\\ __**Going on Sky**__\\ \\ __5.1 Opening the Telescope Domes and enclosures__\\ \\  You can begin opening the telescope domes and enclosures about an hour or two before sunset. This will help air out the domes and improve seeing at the start of the night. Hot days benefit from an earlier opening to allow the scopes to cool. Before opening the domes make sure to check the current weather conditions and the forecast to make sure conditions are safe to open and are likely to be stable as you wait for it to get dark. Also confirm that Judit has finished the alignments in the lab as opening the domes will not allow the completion of the M10 alignments. If you do not see her, call the computer room phone number listed on the clipboard on the wall.\\
   * Monitor the progress of opening the domes by turning the televisions [ON] using the telescope GUIs. Click [SPY1] to view the dome slit.

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