Solar eclipse

About: Solar eclipse is a research topic. Over the lifetime, 2737 publications have been published within this topic receiving 22625 citations.

Effect of solar eclipse on the behavior of a captive group of hamadryas baboons (Papio hamadryas)

Abstract: To date there have been no systematic studies on the effects of a solar eclipse on the behavior of nonhuman primates. However, some descriptive studies have reported an increase in inactivity levels and congregation of individuals during a solar eclipse. The aim of the present work was to carry out a systematic study of the effect of a solar eclipse on the behavior of baboons at an individual, gender, and one-male unit (OMU) level. On 3 November 1994, Chile experienced a solar eclipse. A hamadryas baboon colony grouped in two OMUs at the Zoo of Santiago de Chile was observed 2 days before the solar eclipse (control situation), and during the eclipse for the same time period. Two observers simultaneously sampled the data. An all-occurrence sampling method was used to collect data on threats and attacks made by adult individuals. Simultaneously, instantaneous samplings of 1 min each were used to record behavioral states of the two males and two females. In relation to the control situation, the effect of the solar eclipse on baboon behavior was a reduction in the rates of locomotion and threats, and an increase in the rates of inactivity and grooming, but not significantly so in all the focal individuals. Behavioral changes were more marked in males than in females, but did not differ between the two OMUs. Air temperature and humidity were similar in the two situations, and can therefore be discarded as causal effects on the behavioral changes of the baboons during the eclipse. Zoo Biol 22:299–303, 2003. © 2003 Wiley-Sons, Inc.

Investigation of emission lines of the solar corona of 10 July, 1972 using the Fabry-Pérot etalon

Abstract: Coronal interferograms in the lines of Fe xiv 5303 A, He i 5876 A and Fe x 6374 A were obtained during the total solar eclipse of 10 July, 1972 (see Figure 2). He i emission was found in the chromosphere only. The upper limit of the D3 equivalent width in terms of the coronal continuous background is 0.013 A in the inner corona (r=1.15 R⊙). The λ6374 negative was taken with low contrast. The half width of 16374 is 1.0–1.08 A for a limited area of the corona (P=88−104°, r=1.30−1.44 R⊙). A detailed photometry of the 5303 A line was carried out and the behaviour of the half widths and equivalent widths were studied in different regions of the corona. The half width of λ5303 increases with distance from the Sun's center in almost all the studied regions (1.2 R⊙ ⩽ r ⩽ 1.7 R⊙). This increase corresponds to an increase of the non-thermal velocities with a gradient of 1–2 km s-1 per 0.1 R⊙. The equivalent widths, expressed in the coronal continuous background intensity remain constant on the average.

The earliest known record of a solar eclipse.

Abstract: One of the Ugaritic texts of the Second Millennium BC describes a total eclipse of the Sun. The date is established as 1375 BC, May 3.

Why Is the Sun's Corona So Hot?

Abstract: Yes, the sun is hot—really hot. It9s 16 million kelvin at its fusion-fueled core, cooling, as the second law of thermodynamics requires, to a still-blistering 5780 K at its visible surface. But for the better part of a century, solar physicists have been mystified by the sun9s ability to reheat its corona, the encircling wispy crown of light that emerges from the glare during a total solar eclipse. There, temperatures again soar to 1 million K and more. How would heat dissipating from the core out beyond the surface abruptly punch temperatures up by a factor of 200 and more?