Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Detection of Leonids meteoric dust in the upper atmosphere by
  polarization measurements of the twilight sky   The method of detection of dust in the stratosphere and mesosphere by the
twilight sky background observations is being considered. The polarization
measurements are effective for detection of the meteoric dust scattering on the
background consisting basically of troposphere multiple scattering. The method
is based on the observed and explained polarization properties of the sky
background during different stages of twilight. It is used to detect the
mesosphere dust after the Leonids maximum in 2002 and to investigate its
evolution. The polarization method takes into account the multiple scattering
and sufficient contribution of moonlight scattering background and turns out to
be more sensitive than existing analogs used in the present time.

1
The categories of this paper are: cs
29
The categories of this paper are: funct-an
5
The categories of this paper are: gr-qc
7
The categories of this paper are: hep-th
21
The categories of this paper are: adap-org
28
The categories of this paper are: alg-geom
16
The categories of this paper are: stat
17
The categories of this paper are: q-fin
3
The categories of this paper are: physics
37
The categories of this paper are: supr-con
9
The categories of this paper are: nlin
15
The categories of this paper are: nucl-ex
35
The categories of this paper are: mtrl-th
25
The categories of this paper are: patt-sol
26
The categories of this paper are: bayes-an
34
The categories of this paper are: chem-ph