Welcome to the new version of CaltechAUTHORS. Login is currently restricted to library staff. If you notice any issues, please email coda@library.caltech.edu
Published March 10, 2006 | Submitted + Published
Journal Article Open

Photometric observations constraining the size, shape, and albedo of 2003 EL61, a rapidly rotating, Pluto-sized object in the Kuiper Belt

Abstract

We present measurements at optical wavelengths of the spectral reflectance, rotational light curve, and solar phase curve of 2003 EL61. With apparent visual magnitude 17.5 at 51 AU from the Sun, this newly discovered member of the classical Kuiper Belt is now the third brightest KBO after Pluto and 2005 FY9. Our observations reveal an unambiguous, double-peaked rotational light curve with period 3.9154 ± 0.0002 hr and peak-to-peak amplitude 0.28 ± 0.04 mag. This is the fastest rotation period reliably determined for any body in the solar system larger than 100 km. Assuming the body has relaxed over time to the shape taken by a homogenous fluid body, our observations tightly constrain the shape and density. Given the mass we recently determined for 2003 EL61 from the orbit of a small satellite, we also constrain the size and albedo. We find a total length of 1960–2500 km, a mean density of 2600–3340 kg m^-3, and a visual albedo greater than 0.6. We also measure a neutral reflectance at visible wavelengths and a linear phase curve with slope varying from 0.09 mag deg^-1 in the B band to 0.13 mag deg^-1 in the I band. The absolute V-band magnitude is 0.444 ± 0.021.

Additional Information

© 2006 The American Astronomical Society. Received 2005 September 14; accepted 2005 November 9. This work was supported by grants from NASA Planetary Astronomy.

Attached Files

Published - RABapj06.pdf

Submitted - 0509401.pdf

Files

RABapj06.pdf
Files (859.7 kB)
Name Size Download all
md5:e68c0ebd3f787e45d4e10d76c7a0338c
489.5 kB Preview Download
md5:baf0e301a956a10559a3185296c440b7
370.2 kB Preview Download

Additional details

Created:
August 22, 2023
Modified:
October 23, 2023