Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Stability of the interstellar hydrogen inflow longitude from 20 years of
  SOHO/SWAN observations   Aims. A recent debate on the decade-long stability of the interstellar He
flow vector, and in particular the flow longitude, has prompted us to check for
any variability in the interstellar H flow vector as observed by the SWAN
instrument on board SOHO. Methods. We used a simple model-independent method to
determine the interstellar H flow longitude, based on the parallax effects
induced on the Lyman-{\alpha} intensity measured by SWAN following the
satellite motion around the Sun. Results. Our results show that the
interstellar H flow vector longitude does not vary significantly from an
average value of 252.9$^{\circ}$ $\pm$ 1.4$^{\circ}$ throughout the 20-year
span of the SWAN dataset, further strengthening the arguments for the stability
of the interstellar gas flow.

21
The categories of this paper are: adap-org
0
The categories of this paper are: hep-ph
14
The categories of this paper are: math-ph
22
The categories of this paper are: chao-dyn
19
The categories of this paper are: eess
25
The categories of this paper are: patt-sol
1
The categories of this paper are: cs
11
The categories of this paper are: hep-lat
37
The categories of this paper are: supr-con
10
The categories of this paper are: q-bio
15
The categories of this paper are: nucl-ex
16
The categories of this paper are: stat
30
The categories of this paper are: q-alg
5
The categories of this paper are: gr-qc
4
The categories of this paper are: cond-mat
26
The categories of this paper are: bayes-an