diff --git a/citydist.py b/citydist.py
index f492694..ed33ce7 100644
--- a/citydist.py
+++ b/citydist.py
@@ -2,9 +2,15 @@ import numpy as np
 import pandas as pd
 from pyproj import Geod
 
-def closest_coord_point(point):
-    cities = pd.read_csv("africapolis.csv", index_col=0)
-    oco = pd.read_csv("oco2.csv", index_col=0)
+def closest_satalite_measurement(point, df=None):
+    if df is None:
+        df = pd.read_csv("oco2.csv", index_col=0)
+    geod = Geod(ellps="WGS84")
+    pos = df.apply(lambda row: geod.inv(point[1], point[0], row["Longitude"], row["Latitude"]), axis=1)
+    distances = pos.apply(lambda row: row[2])
+    min_index = distances.idxmin()
+    measurement = df.loc[min_index]
+    return dict(measurement)
 
 def closest_city(point, df=None, population_threshold=0):