Sentences with phrase «sunspot faculae»

Not exact matches

This object had an almost circular shape, and a light beam came out from its eastern part that crossed the sunspot to the south of the nucleus, producing a shadow on the penumbra that was lost in the large mass of faculae surrounding the eastern extreme of the sunspot.»

There is an excess of H and K emission in the faculae which surround sunspots, and epochs of sunspot maximum coincide with epochs of maximum H and K.

Because of the variations of sunspots and faculae on the sun's surface, the total solar irradiance (TSI), also called the solar constant, varies on a roughly 11 - year cycle by about 0.07 %, which has been measured by orbiting satellites since 1978 [Lean, 1987, 1991; Wilson et al., 1981].

«Despite the fact that ACRIM I, ACRIM II, ACRIM III, VIRGO and TIM all track degradation with redundant cavities, notable and unexplained differences remain in irradiance and the modeled influences of sunspots and faculae.

Foukal point out correctly that the arguments used for supporting a long term solar component — other than that related to sunspot / faculae — have fallen down.

This increase has not been measured by the other satellite measuring at this period (ERBS); b) other indicators of solar activity, which are closely correlated to TSI (sunspot number, faculae, geomagnetic activity) show no trend in that period, either.

Key words: Sun: activity / sunspots / Sun: UV radiation / Sun: faculae, plages / Sun: magnetic fields / Sun: photosphere

Since the solar UV irradiance has no long - term trend, the mechanism for the secular change of TSI must differ from the effect of surface magnetism, as manifested by sunspots, faculae, and network which indeed explain well the intra-cycle variability of both total and spectral irradiance.

They noted that empirical models based upon sunspots and faculae do not account for all irradiance variations observed over an activity cycle (see also NRC (1994)-RRB- and base their con - elation on an observed relationship between brightness and excess chromospheric emission, using the Ca II H and...»

Fewer sunspots meant fewer faculae, so less heat from the Sun.

Sunspots are surrounded by a rim called faculae, and in this region the temperatures are actually higher than the average solar surface.

In this study, we address the question of whether the observed decrease in the TSI is the result of evolving solar surface magnetism (sunspots and faculae).

Key words: methods: data analysis / solar - terrestrial relations / Sun: activity / Sun: faculae, plages / Sun: magnetic fields / sunspots

We use a TSI model that is solely based on solar surface magnetic phenomena (sunspots and faculae including network).

Because our main goal is to reproduce the centennial solar variability and because magnetograms are unavailable for historical time periods, we scale the faculae and the active network filling factors with the sunspot number instead of using filling factors derived from available magnetogram data.

Key words: Sun: solar - terrestrial relations / methods: data analysis / Sun: activity / Sun: faculae, plages / Sun: magnetic fields / Sun: sunspots

A time series of daily magnetograms and empirical models of the thermal structure of magnetic features (sunspots, faculae) are combined to reconstruct total (and spectral) irradiance from 1996 to 2002.

A picture of dark sunspots and bright diffuse faculae (best seen around the edges).