Debris disk around the star HD 53143 by the Hubble Space Telescope. The star itself has been hidden by the camera coronograph to make the disk visible.
Using the technique of gyrochronology, which measures the age of a low-mass star based on its rotation, HD 53143 is about 1,010 ± 130 million years old.[10] Depending on the source, the stellar classification for this star is G9 V[4] or K1V,[6] placing it near the borderline between G-type and K-type main sequence stars. In either case, it is generating energy through the thermonuclear fusion of hydrogen at its core. This star is smaller than the Sun, with about 85% of the Sun's radius.[7] It is emitting only 70% of the Sun's luminosity. The effective temperature of the star's outer envelope is cooler than the Sun at 5,224 K, giving it a golden-orange hue.[6]
Based upon an excess of infrared emission, a circumstellar debris disk has been found in this system.[12] This disk is inclined at an angle of about 40–50° to the line of sight from the Earth and it has an estimated mass of more than 7 × 1020 kg. (For comparison, the mass of the Moon is 7.3477 × 1022 kg.) This is one of the oldest known debris disk systems and hence may be replenished through the collision of larger bodies. The observed inner edge of the disk is at a distance of 55 Astronomical Units (AU) from the host star, while it stretches out to twice that distance, or 110 AU. This debris disk may extend outside this range, as the measurements are limited by the sensitivity of the instruments. The dust appears evenly distributed with no indication of clumping.[6] The eccentricity of the ring is also one of the highest known, at 0.21.[9]
^Cousins, A. W. J. (1973), "UBV photometry of some southern stars", Monthly Notes of the Astronomical Society of Southern Africa, 32: 11, Bibcode:1973MNSSA..32...11C
^Evans, D. S. (June 20–24, 1966), "The Revision of the General Catalogue of Radial Velocities", in Alan Henry, Batten; Heard, John Frederick (eds.), Determination of Radial Velocities and their Applications, Proceedings from IAU Symposium no. 30, vol. 30, University of Toronto: International Astronomical Union, p. 57, Bibcode:1967IAUS...30...57E
