[education/kstars] doc: Correct a typo in darkmatter.docbook

[Felix Yan]

Git commit 83568b23178bbf803ae795e45e86881a79498690 by Felix Yan.
Committed on 23/10/2020 at 20:15.
Pushed by yurchor into branch 'master'.

Correct a typo in darkmatter.docbook

M  +1    -1    doc/darkmatter.docbook

https://invent.kde.org/education/kstars/commit/83568b23178bbf803ae795e45e86881a79498690

diff --git a/doc/darkmatter.docbook b/doc/darkmatter.docbook
index 2286bcb36..58de1c020 100644
--- a/doc/darkmatter.docbook
+++ b/doc/darkmatter.docbook
@@ -46,7 +46,7 @@ galaxy in the cluster based on their luminosity, and added up all of
 the galaxy masses to get a total cluster mass.  He then made a second,
 independent estimate of the cluster mass, based on measuring the
 spread in velocities of the individual galaxies in the cluster.
-To his suprise, this second <firstterm>dynamical mass</firstterm>
+To his surprise, this second <firstterm>dynamical mass</firstterm>
 estimate was <emphasis>400 times</emphasis> larger than the estimate
 based on the galaxy light.
 </para>