diff --git a/agenda/thespacedevs.py b/agenda/thespacedevs.py
index 6ece23c..23e2887 100644
--- a/agenda/thespacedevs.py
+++ b/agenda/thespacedevs.py
@@ -10,6 +10,8 @@ import httpx
 Launch = dict[str, typing.Any]
 Summary = dict[str, typing.Any]
 
+ttl = 60 * 60 * 2  # two hours
+
 
 async def next_launch_api(rocket_dir: str, limit: int = 200) -> list[Launch]:
     """Get the next upcoming launches from the API."""
@@ -137,14 +139,16 @@ def summarize_launch(launch: Launch) -> Summary:
     }
 
 
-async def get_launches(rocket_dir: str, limit: int = 200) -> list[Summary]:
+async def get_launches(
+    rocket_dir: str, limit: int = 200, refresh: bool = False
+) -> list[Summary]:
     """Get rocket launches with caching."""
     now = datetime.now()
     existing = [x for x in (filename_timestamp(f) for f in os.listdir(rocket_dir)) if x]
 
     existing.sort(reverse=True)
 
-    if not existing or (now - existing[0][0]).seconds > 3600:  # one hour
+    if refresh or not existing or (now - existing[0][0]).seconds > ttl:
         try:
             return await next_launch_api(rocket_dir, limit=limit)
         except httpx.ReadTimeout:
diff --git a/update_thespacedevs.py b/update_thespacedevs.py
new file mode 100755
index 0000000..9ecec7e
--- /dev/null
+++ b/update_thespacedevs.py
@@ -0,0 +1,26 @@
+#!/usr/bin/python3
+"""Update cache of space launch API."""
+
+import asyncio
+import os
+import sys
+from time import time
+
+import agenda.thespacedevs
+
+config = __import__("config.default", fromlist=[""])
+rocket_dir = os.path.join(config.DATA_DIR, "thespacedevs")
+
+
+async def get_launches() -> list[agenda.thespacedevs.Launch]:
+    """Call space launch API and cache results."""
+    return await agenda.thespacedevs.get_launches(rocket_dir, limit=200, refresh=True)
+
+
+t0 = time()
+rockets = asyncio.run(get_launches())
+time_taken = time() - t0
+if not sys.stdin.isatty():
+    sys.exit(0)
+print(len(rockets), "launches")
+print(f"took {time_taken:.1f} seconds")