HD 4222 and BU 492B make up the binary system BU 492. The companion is a
red dwarf with a stellar classification of M2-5V; it is located 1.5" away from the primary along a
position angle of 173°. BU 492B was first noticed by
astronomer S. W. Burnham in 1878. HD 4222 also has one optical companion; an 11th magnitude star located 88.6" away, which itself is also a
double star.[4] A
X-ray emission with a luminosity of 3.031×1020W was detected around the star.[9]A-type stars are not expected to emit X-rays, so it might be coming from the companion. HD 4222 is considered to be a probable member of the
Sirius supercluster, a group of stars moving with the bright star
Sirius and share a common origin with the system.[18]
^
abWilson, Ralph Elmer (1953). "General catalogue of stellar radial velocities". Carnegie Institute Washington D.C. Publication: 0.
Bibcode:
1953GCRV..C......0W.
S2CID120000732.
^
abFracassini, M.; Manzolini, F.; Pasinetti, L. E.; Ruggenini, M. (May 1980). "Apparent radii and other parameters for 416 B5 V-F5 V stars of the catalogue of the Geneva observatory". Astrophysics and Space Science. 69 (2). Springer Science and Business Media LLC: 401–423.
Bibcode:
1980Ap&SS..69..401F.
doi:
10.1007/bf00661927.
ISSN0004-640X.
S2CID189849072.
HD 4222 and BU 492B make up the binary system BU 492. The companion is a
red dwarf with a stellar classification of M2-5V; it is located 1.5" away from the primary along a
position angle of 173°. BU 492B was first noticed by
astronomer S. W. Burnham in 1878. HD 4222 also has one optical companion; an 11th magnitude star located 88.6" away, which itself is also a
double star.[4] A
X-ray emission with a luminosity of 3.031×1020W was detected around the star.[9]A-type stars are not expected to emit X-rays, so it might be coming from the companion. HD 4222 is considered to be a probable member of the
Sirius supercluster, a group of stars moving with the bright star
Sirius and share a common origin with the system.[18]
^
abWilson, Ralph Elmer (1953). "General catalogue of stellar radial velocities". Carnegie Institute Washington D.C. Publication: 0.
Bibcode:
1953GCRV..C......0W.
S2CID120000732.
^
abFracassini, M.; Manzolini, F.; Pasinetti, L. E.; Ruggenini, M. (May 1980). "Apparent radii and other parameters for 416 B5 V-F5 V stars of the catalogue of the Geneva observatory". Astrophysics and Space Science. 69 (2). Springer Science and Business Media LLC: 401–423.
Bibcode:
1980Ap&SS..69..401F.
doi:
10.1007/bf00661927.
ISSN0004-640X.
S2CID189849072.