In the April 2018 issue of TPT, Joseph Amato presented an analysis of intercontinental ballistic missile (ICBM) trajectories as applied to recent test launches from North Korea. Using properties of their elliptical paths, he derived relationships between launch velocity, elevation angle, and maximum range. However, this approach cannot include the effects of Earth’s rotation, even though they should be significant for ICBM speeds ≈ 6 km/s and flight times ≈ 25 min. Here I use the aerospace industry software Systems Tool Kit (STK), freely available for school use, to model ICBM paths launched from various locations on a spinning globe. The results illustrate the effects of a rotating Earth on ballistic motion, while demonstrating STK’s utility as a simulation tool for educators and students.

1.
J.
Amato
, “
Using elementary mechanics to estimate the maximum range of ICBMs
,”
Phys. Teach.
56
,
210
213
(April
2018
).
2.
See the solution to
Physics Challenge for Teachers and Students
: “
One giant leap
,”
Phys. Teach.
50
,
568
(Dec.
2012
).
3.
C.
Scherr
, “
From snowballs to ICBMs
,”
Am. J. Phys.
47
,
329
330
(April
1979
).
4.
L.
Burko
and
R.
Price
, “
Ballistic trajectory: Parabola, ellipse, or what?
Am. J. Phys.
73
,
516
520
(May
2005
).
5.
A.
Shakur
, “
Debunking Coriolis force myths
,”
Phys. Teach.
52
,
464
465
(Nov.
2014
).
6.
R.
Bate
,
D.
Mueller
, and
J.
White
,
Fundamentals of Astrodynamics
(
Dover
,
New York
,
1971
), Sec. 6.4.
7.
F.
Orlando
,
C.
Farina
,
Z.
Zarro
, and
P.
Terra
, “
Kepler’s equation and some of its pearls
,”
Am. J. Phys.
86
,
849
858
(Nov.
2018
).
8.
STK is capable of modeling boost-phase dynamics of multi-stage ICBMs, in addition to atmospheric drag, solar radiation pressure, and gravitational perturbations. However, these effects were disabled for the simulations presented here
.
9.
J.
Lincoln
, “
Using Python as a toolbox for student-directed virtual labs
,”
Phys. Teach.
57
,
60
61
(Jan.
2019
).
10.
For example, search for aerospace careers at http://www.indeed.com using the phrase “
STK engineer.
11.
To learn more about AGI’s Educational Alliance Program
, visit http://www.agi.com/education.
12.
This annual competition is sponsored by the Air Force Association
. Visit http://www.stellarxplorers.org.
13.
See the online supplementary materials at TPT Online, http://dx.doi.org/10.1119/10.0002070, under the Supplemental tab.

Supplementary Material

AAPT members receive access to The Physics Teacher and the American Journal of Physics as a member benefit. To learn more about this member benefit and becoming an AAPT member, visit the Joining AAPT page.