Extracted Data Points

  • Kodaikanal solar observatory maintains the oldest continuous series of solar data collected in India
  • Study analyzed 100 years of solar data from Kodaikanal archival data starting from 1907
  • Researchers examined 34,000 Ca II K spectroheliograms for the analysis
  • Convective cells on Sun's surface have average lifetime of 24 hours and size of about 30,000 km
  • Cooler intergranular lanes have width of about 6,000 km
  • Lane widths and intensities correlate strongly with sunspot numbers, peaking around +/-(11–22)° latitude
  • Peak correlation for lane widths occurs at (18 +/- 2)°N and (20 +/- 2)°S latitudes
  • Peak correlation for intensities occurs at (13 +/- 2)°N and (14 +/- 2)°S latitudes
  • Lane width correlations peak during solar maximum
  • Intensity correlations peak 1.25–1.5 years after solar maximum
  • Time lag varies with latitude: zero near ±20°, decreasing towards higher latitudes, and increasing towards equator
  • For lane widths, lag ranges from 0.5 to 0.8 years
  • For intensities, lag varies from 0.3 to about 2.5 years
  • Data covers more than nine solar cycles
  • Study published in Astrophysical Journal Letters