The Sun's shape and brightness

J. R. Kuhn (), R. I. Bush, X. Scheick and P. Scherrer
Additional contact information
J. R. Kuhn: Michigan State University, East Lansing
R. I. Bush: Stanford University
X. Scheick: Jackson Community College
P. Scherrer: Stanford University

Nature, 1998, vol. 392, issue 6672, 155-157

Abstract: Abstract The origin of the 11- and 22-year solar cycles remains one of the more mysterious aspects of the Sun. These cycles are probably driven by convection in the solar interior, but the convection zone is difficult to probe. Small departures from sphericity in the effective surface temperature of the Sun can in principle be used in this regard. Such variations, which are observed as changes in the surface brightness with solar latitude, may be caused by differences between the vertical and horizontal turbulent convective flows1 inside the Sun. Moreover, variations in the Sun's luminosity may be related to changes in conditions near the base of the convection zone2 that result from the magnetic (sunspot) cycle3. Here we present satellite data that show that the Sun's shape and temperature vary with latitude in an unexpectedly complex way. Although the solar oblateness shows no evidence of varying with the solar cycle, we find a significant hexadecapole shape term which may vary. We also see a variation of about 1.5 K in the surface temperature with latitude. Based on these results, we suggest that sensitive observations of brightness variations be used as a record of the surface ‘shadow’ of cyclical changes in the solar interior.

Date: 1998
References: Add references at CitEc
Citations:

Downloads: (external link)
https://www.nature.com/articles/32361 Abstract (text/html)
Access to the full text of the articles in this series is restricted.

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:nat:nature:v:392:y:1998:i:6672:d:10.1038_32361

Ordering information: This journal article can be ordered from
https://www.nature.com/

DOI: 10.1038/32361

Access Statistics for this article

Nature is currently edited by Magdalena Skipper

More articles in Nature from Nature
Bibliographic data for series maintained by Sonal Shukla () and Springer Nature Abstracting and Indexing ().