Show changes in launch JSON

update.py

@@ -9,6 +9,7 @@ import typing
 from datetime import date, datetime
 from time import time
 
+import deepdiff  # type: ignore
 import flask
 import requests
 
@@ -87,16 +88,14 @@ def report_space_launch_change(
         name = prev_launch["name"]
     subject = f"Change to {name}"
 
+    differences = deepdiff.DeepDiff(prev_launch, cur_launch)
+
     body = f"""
 A space launch of interest was updated.
 
 Get ready for two big piles of JSON.
 
-Old launch data
-{json.dumps(prev_launch, indent=2)}
-
-New launch data
-{json.dumps(cur_launch, indent=2)}
+{json.dumps(differences, indent=2)}
     """
 
     agenda.mail.send_mail(config, subject, body)