Error Boxes and Help Files

Your observations are checked by the computer. There are many things that we look at to determine if your observations are good.

Did you forget what those wierd three-lettered acronyms meant?
Would you like to re-read those nice help files again without having to log back into the Moon Project System ?

In that case, this is the web page for you! We have consolidated all those javascript error boxes and help files onto one page!
Choose from the following:


Feel free to scroll down and browse around as well.

If you don't know how to fill out the sheet on paper, you should click and read this link instead: Observation Sheet Instructions.


Quick Pick
[SUB ] [OBS ] [CST ] [DAY ] [PHN ] [MHF ] [MHD ] [SHC ] [EHA ] [EDT ] [UP ]

SUB: Submission time check

You did not turn in your observation within the designated time period (this is set by your TA).

Commonly Made Mistakes

  1. You did not turn in your observations on time. Whenever you take an observation, you have 72 hours (unless specified otherwise by your TA) to submit your obse rvations on-line. Otherwise, it is rejected.
  2. Consider this process as you would a time sheet: You write down your hours, you get paid. If you don't write down your hours, you don't get paid.
  3. If you do not submit your observations on-time, you will have no observations at all by the time the semester is over.

OBS: Observation period check

You did not wait the appropriate amount of time before taking another observation (this is set by your TA).

Commonly Made Mistakes

  • Wait for the appropriate amount of time before taking another observation.
  • CST: Central Standard Time check

    You did not calculate your CST correctly from your Clock Time.

    Commonly Made Mistakes:

  • Daylight Savings is between early April and late October.
  • Here are two examples of Clock Time to CST conversion:
  • 1. If you are in Daylight Savings, 6:35 PM --> 17:35 --> 17.58
  • 2. If not, then 6:35 PM --> 18:35 PM --> 18.58
  • DAY: Day Number check

    Your day number does not match your observation date.

    Commonly Made Mistakes:

    1. Click HERE for the list of day numbers.
    2. 30 days hath September, April, June, and November. All the rest have 31. Except for February which has 28 (unless it is a leap year, in which case it has 29 days).
    3. There is no such thing as Day 0. Jan 1st is Day 1.

    MHF: Moon's HA from your Fist calculation check

    You did not calculate your Moon's HA correctly from your fists (hands).

    Commonly Made Mistakes:

    1. If the Moon was East, your FIST/HAND should be negative.
    2. Don't know how to take a measurement? Click here.
    3. You might have mistaken East and West directions.
    4. Try not to switch between FISTS and HANDS. Choose one and stick with it for the rest of the semester.
    5. Did you change your 'Degrees per fists/hands'? If so, you should change your settings above.
    EXAMPLE: The Moon was 3.3 FISTS East. If each FIST is 10 degrees, then Moon's HA = -3.3 * 10 = -33.

    MHD: Moon's HA on that Date check

    Commonly Made Mistakes:

    1. Are you sure of the direction of the Moon? Was the Moon in the East or in the West?
    2. Are you sure you are facing South?

    Otherwise, please see your TA.

    PHN: Phase Number/Sketch check

    Your phase number and phase sketch do not match.

    Commonly Made Mistakes:

    1. When drawing the Moon phase on a piece of paper, you might mistake light for dark and dark for light.
    2. Your phase sketch might not be matching your phase number. Either your phase sketch is wrong or your phase number is wrong.

    SHC: Sun's HA Calculation check

    You did not calculate the Sun's HA from your CST correctly.

    Commonly Made Mistakes:

    1. Order of operations makes a difference. Do the subtraction first (CST - 12) before you multiply by 15.
    2. It is ok if the Sun's HA is negative. Leave it as it is.
    3. Did you calculate your CST correctly?

    EHA: Elongation from your Moon's and Sun's Hour Angle Calculation check

    You did not calculate your elongation correctly from your Sun's HA and Moon's HA

    Commonly Made Mistakes:

    1. Elongation can never be negative. If it is, add 360. This will make it positive.
    2. Elongation can only go from 0 to 359.99. 360 is the same thing as 0.

    EDT: Elongation on that Date check

    Commonly Made Mistakes:

    1. The calculation for Elongation depends on two things: Moon's HA and Sun's HA. Check to see if they are both correct.
    2. If Sun's HA (SHC box) is red, please fix the Sun's HA calculation.
    3. If Moon's HA (MHF box) is red, please fix the Moon's HA calculation.

    Otherwise, please see your TA.

    UP: Moon Up check

    According to the computer, the Moon was not up when you made your observation.

    Commonly Made Mistakes:

    Are you sure you're looking at the Moon? You may have been looking at:
  • The Sun
  • Clouds
  • Spotlight
  • Quick Pick
    [SUB ] [OBS ] [CST ] [DAY ] [PHN ] [MHF ] [MHD ] [SHC ] [EHA ] [EDT ] [UP ]



    The computer records the date and time you submitted your observation or made a modification.


    Type in the date of your observation.
    The format is: MM-DD-YYYY


    Look at your clock and write down the time you saw the Moon.
    Use the AM/PM method here.


    Convert your Clock Time to Decimal CST. Follow the methods below.
    1. If you observation is in PM, add 12 hours.
    2. Are you in daylight savings time? If so, subtract 1 hour.
    3. Divide the minutes by 60.


    This column has the following information about your observation:
  • Observation Date
  • Observation Clock Time
  • Decimal CST

    Choose the image that best represents what you saw in the sky.


    Write down the phase # that best represents what you saw in the sky. For example: 2.3, 4.0, 5.6, 7.5, etc...


    This is where you write down your measurement of the Moon (the number of fists you counted).

    This project is not a guessing game. Do not randomly type in numbers in the hopes of getting something right. This is considered academic misconduct.

    1. Type in the number of fists you counted (e.g. 3.2, 1.5, 5.4, etc...), but use the drop down menu to select the direction (East or West).
    2. We encourage you to use two significant digits for your observations.


    FISTS (or HANDS) * Degrees per FIST (or HANDS) = Moon's H.A.
    If the Moon was in the East, please choose East in the pulldown menu.
    If the Moon was in the West, please choose West in the pulldown menu.
    This direction should match the direction on your fist count.


    Write down the day number for the date you took the observation. For example, Jan 1 = Day 1, Jan 2 = Day 2, Jan 31 = Day 31, Feb 1 = Day 32, Feb 2 =Day 33, etc.... You can also find the day number on this table


    [ CST - 12 ] * 15 = Sun's H.A.
    Please write down a positive number and choose the direction (sign) from the pulldown menu.
    If the Sun HA you calculated is negative, the Sun was in the East.
    If the Sun HA you calculated is positive, the Sun was in the West.


    Sun's H.A. - Moon's H.A. = Moon Elongation
    Keept in mind the directions of your hour angles (West=positive East=negative) while doing the calculation.  


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