HD 139664
HR 5825 HIP 76829 g Lup
RA (2000) = 15 41 11.3774
Dec (2000) = -44 39 40.338
SpT = F5IV - V
V = 4.64 mag d = 17.52 pc
Proper Motion (mas/yr) = -168.70 -265.69
This is an optical Hubble Space Telescope image of dust scattered
light (reflection nebulosity) around the F5V star HD 139664.
The central star is actually blocked by a small black spot
in the optical path of Hubble's camera, producing an artificial
eclipse of the star, and thus revealing the faint surrounding material that
is illuminated by the star. The disk is viewed near edge-on.
Basic facts about HD 139664
1) The structure is a ring with inner and outer radii of 60 and 109 AU, respectively.
2) The ring is seen 0 - 5 degrees from edge-on from our point of view.
3) Various age indicators show that the system is 300 million years old.