Imaging the surface of Altair.
Spatially resolving the surfaces of nearby stars promises to advance our knowledge of stellar physics. Using optical long-baseline interferometry, we constructed a near-infrared image of the rapidly rotating hot star Altair with a resolution of <1 milliarcsecond. The image clearly reveals the strong effect of gravity darkening on the highly distorted stellar photosphere. Standard models for a uniformly rotating star cannot explain our findings, which appear to result from differential rotation, alternative gravity-darkening laws, or both.
Monnier
John D
JD
Department of Astronomy, University of Michigan, Ann Arbor, MI 48109, USA. monnier@umich.edu
Zhao
M
M
Pedretti
E
E
Thureau
N
N
Ireland
M
M
Muirhead
P
P
Berger
J-P
JP
Millan-Gabet
R
R
Van Belle
G
G
Ten Brummelaar
T
T
McAlister
H
H
Ridgway
S
S
Turner
N
N
Sturmann
L
L
Sturmann
J
J
Berger
D
D