diff --git a/public/js/appChart.js b/public/js/appChart.js
index be10d07883bc658bb8587d57725a31b1a1325f52..af9855173765194e4212d15d1be14aa287cf055d 100644
--- a/public/js/appChart.js
+++ b/public/js/appChart.js
@@ -846,6 +846,29 @@ const formatSTAResponseForScatterPlot = function (obsArrayOne, obsArrayTwo) {
     obsArrayTwoTimestamp
   );
   console.log(missingTimestamp);
+
+  /**
+   *
+   * @param {Array} missingTimestampsArr An array of strings representing the missing timestamps
+   * @param {Array} firstObsTimestampArr An array of timestamps for the first set of observations
+   * @returns {Array} An array of the indexes of the missing observations
+   */
+  const getIndexOfMissingObservation = function (
+    missingTimestampsArr,
+    firstObsTimestampArr
+  ) {
+    const indexesMissingObs = missingTimestampsArr.map((index) =>
+      firstObsTimestampArr.indexOf(index)
+    );
+
+    // console.log(indexes);
+    return indexesMissingObs;
+  };
+
+  const indexesMissingObsArr = getIndexOfMissingObservation(
+    missingTimestamp,
+    obsArrayOneTimestamp
+  );
 };
 
 (async () => {