Secular Acceleration of Io Derived from Mutual Satellite Events

Details Secular Acceleration of Io Derived from Mutual Satellite Events Secular Acceleration of Io Derived from Mutual Satellite Events

Nov 2001

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2001aj....122.2734a&link_type=abstract

The Astronomical Journal, Volume 122, Issue 5, pp. 2734-2739.

Astronomy and Astrophysics

Astronomy

23

Celestial Mechanics, Occultations, Planets And Satellites: Individual (Callisto, Europa, Ganymede, Io)

Scientific paper

Timings and light curves of the mutual phenomena of the Galilean satellites in 1908, 1914, and 1973-1997 have been used first to improve the values of the most important parameters in Sampson's satellite theory (published in 1921) and second to reduce the considerable remaining discrepancies in the observations by solving for constant changes, Δni, and rates, ni, in the mean motions of the four satellites. Earlier determinations of the n values-primarily n1-have been based mainly on observations of ordinary eclipses that are much less precise than the mutual event observations and also suffer from uncertainty in the UT-ET correction prior to 1900. Because of strong correlations, it is not possible to obtain meaningful least-squares solutions for both Δni and ni, except for Io for which we obtain Δn1=(0.4+/-1.1)×10-6 deg day-1 and n1/n1=3.6+/-1.0 in units of 10-10 yr-1. This Δn1 value is comparable to the values determined for Δn2, Δn3, and Δn4. Although the data can be satisfied nearly as well by correcting only the mean motions, this leads to a 10 times larger Δn1 value, which seems unacceptably large. Furthermore, n1=0 would require an unphysically large tidal torque from Jupiter to overcome Io's orbital decay because of the observed energy dissipation in Io. Our determination of n1/n1 is in reasonable agreement with the values 3.3+/-0.5 (from de Sitter, published in 1928) and 4.54+/-0.95 (from Goldstein & Jacobs, published in 1995), both of which were derived from analyses of eclipses of the satellites by Jupiter and some photographic observations. However, it conflicts with the value -0.074+/-0.087 found by Lieske (published in 1987) from Jovian eclipse timings. Our results imply that Io is now spiraling slowly inward, losing more orbital energy from internal dissipation than it gains from Jupiter's tidal torque. These results suggest that Q, the specific dissipation function of Jupiter, is around 200,000 for an Io heat flux of 1.3×1014 W.

Affiliated with

Also associated with

No associations

Rating

Secular Acceleration of Io Derived from Mutual Satellite Events does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Secular Acceleration of Io Derived from Mutual Satellite Events, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Secular Acceleration of Io Derived from Mutual Satellite Events will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1234717