The rotation period of Neptune's upper atmosphere

R. Hamilton Brown, Dale P. Cruikshank, Alan T. Tokunaga

Research output: Contribution to journalArticlepeer-review

27 Scopus citations


Significant variations in the near-infrared brightness of Neptune during July and August 1980 were observed. These observations show a well-defined, large-amplitude variation in Neptune's J-K color, with a period of 17.73 ± 0.1 hr and are interpreted as diurnal variations resulting from the 17.73-hr rotation period of the upper atmosphere of Neptune in the presence of inhomogeneous weather. These results qualitatively corroborate those of D. P. Cruikshank (1978, Astrophys. J. 220, L57-L59) in an earlier study using similar techniques. In addition, variations were observed in the 5-μm spectral region which are in phase with the variations seen at shorter wavelengths. A new 5-μm measurement of Uranus is also reported.

Original languageEnglish (US)
Pages (from-to)159-165
Number of pages7
Issue number2
StatePublished - Aug 1981
Externally publishedYes

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science


Dive into the research topics of 'The rotation period of Neptune's upper atmosphere'. Together they form a unique fingerprint.

Cite this