Solar radius variations over the past 265 years

Journal Article · Tue Sep 15 04:00:00 EDT 1981 · Astrophys. J.; (United States)

DOI:https://doi.org/10.1086/159243· OSTI ID:5625585

Gilliland, R L

Analysis of five different data sets including meridian circle observations, timings of transits of Mercury, and durations of total solar eclipses consistently suggests the presence of a 76 year modulation of the solar radius. The last solar radius maximum occurred in about A. D. 1911, and the half-amplitude of variation is approx.0''.2 (0.02%). The 76 year radius variation is negatively correlated with the Gleissberg cycle of the mean sunspot numbers at the 2 sigma level of significance. A more significant 3 sigma correlation between the solar radius and sunspot cycle is found at 11 years from examination of several independent data sets. Again the correlation is negative, with maximum sunspot number corresponding to minimum solar radius. The half-amplitude of the 11 year variation is approx.0''.1. A secular decrease of approx.0''.1 per century over the last 265 years is also likely from an objective analysis of available data.

• Research Organization: High Altitude Observatory and Advanced Study Program, National Center for Atmosphere Research, Boulder
• OSTI ID: 5625585
• Journal Information: Astrophys. J.; (United States), Journal Name: Astrophys. J.; (United States) Vol. 248:3; ISSN ASJOA
• Country of Publication: United States
• Language: English

Related Subjects

640104* -- Astrophysics & Cosmology-- Solar Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
DATA ANALYSIS
DIMENSIONS
MAGNETIC FIELDS
MAIN SEQUENCE STARS
PHYSICAL PROPERTIES
SOLAR ACTIVITY
SOLAR CYCLE
STARS
SUN
SUNSPOTS
VARIABLE STARS
VARIATIONS