fix spelling

Author: zingale

docs/hse-reconstruction.ipynb

@@ -473,7 +473,7 @@
    "id": "ec8ae681-d63c-4426-8939-898f8e6154fc",
    "metadata": {},
    "source": [
-    "The final variation is to keep the parabola in terms of $p^\\prime$ and do the characterstic tracing\n",
+    "The final variation is to keep the parabola in terms of $p^\\prime$ and do the characteristic tracing\n",
     "on that.  Then we need add back in the HSE interface pressure after the tracing.  \n",
     "\n",
     "A few notes:\n",