Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On detecting the gravitomagnetic field of the earth by means of orbiting
  clocks   Based on the recent finding that the difference in proper time of two clocks
in prograde and retrograde equatorial orbits about the Earth is of the order
10^{-7}s per revolution, the possibility of detecting the terrestrial
gravitomagnetic field by means of clocks carried by satellites is discussed. A
mission taking advantage of this influence of the rotating Earth on the proper
time is outlined and the conceptual difficulties are briefly examined.

31
The categories of this paper are: ao-sci
9
The categories of this paper are: nlin
0
The categories of this paper are: hep-ph
32
The categories of this paper are: atom-ph
37
The categories of this paper are: supr-con
15
The categories of this paper are: nucl-ex
18
The categories of this paper are: econ
2
The categories of this paper are: math
30
The categories of this paper are: q-alg
6
The categories of this paper are: astro-ph
33
The categories of this paper are: plasm-ph
7
The categories of this paper are: hep-th
16
The categories of this paper are: stat
36
The categories of this paper are: cmp-lg
1
The categories of this paper are: cs
27
The categories of this paper are: comp-gas