Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Location of upper borders of cavities containing dust and gas under
  pressure in comets   The distance between the pre-impact surface of Comet 9P/Tempel 1 and the
upper border of the largest cavity excavated during ejection of material after
the collision of the impact module of the Deep Impact spacecraft with the comet
is estimated to be about 5-6 metres if the diameter of the DI transient crater
was about 150-200 m. The estimated distance was 4 m at the diameter was 100 m.
This result suggests that cavities containing dust and gas under pressure
located a few metres below surfaces of comets can be frequent.

3
The categories of this paper are: physics
27
The categories of this paper are: comp-gas
14
The categories of this paper are: math-ph
28
The categories of this paper are: alg-geom
1
The categories of this paper are: cs
21
The categories of this paper are: adap-org
19
The categories of this paper are: eess
8
The categories of this paper are: hep-ex
9
The categories of this paper are: nlin
23
The categories of this paper are: solv-int
15
The categories of this paper are: nucl-ex
0
The categories of this paper are: hep-ph
30
The categories of this paper are: q-alg
2
The categories of this paper are: math
20
The categories of this paper are: acc-phys
36
The categories of this paper are: cmp-lg