<DOC>
<DOCNO>
613
</DOCNO>
<TITLE>
the contraction of satellite orbits under the influence of air drag
part i . with spherically symmetrical atmosphere .
</TITLE>
<AUTHOR>
king-hele, d.g., cook, g.e. and walker, d.m.c.
</AUTHOR>
<BIBLIO>
r.a.e. tn. gw. 533. 1959 .
</BIBLIO>
<TEXT>
the effect of air drag on satellite orbits of small eccentricity e/0.2/
is studied analytically by a perturbation method, on the assumption that
 the atmosphere is spherically symmetrical . equations are derived which
 show/1/how orbital period and perigee distance vary with eccentricity
as the orbit contracts, and/2/how each of these quantities varies with
time . the equations of type/1/are nearly independent of the oblateness
of the atmosphere . in all the equations, terms of order e and higher
are usually neglected . the results are also presented graphically, in a
 manner designed for practical use .
the theory is to be extended to an oblate atmosphere in part ii, and
will later be compared with observation .
</TEXT>
</DOC>
