Related Experiment Video
Updated: Jun 16, 2026
11:38
Influence of Hybrid Perovskite Fabrication Methods on Film Formation, Electronic Structure, and Solar Cell Performance
Published on: February 27, 2017
Spectral changes in the zenith skylight during total solar eclipses.
Applied Optics
|January 30, 2010
Summary
Zenith sky spectral intensity remained constant during a 1970 solar eclipse. Color shifts observed at lower solar angles align with Rayleigh scattering, but higher angles show inconsistencies.
Area of Science:
- Atmospheric optics
- Solar physics
- Spectroscopy
Background:
- Understanding the spectral distribution of the zenith sky is crucial for atmospheric studies.
- Total solar eclipses offer unique opportunities to study atmospheric light scattering.
- Previous measurements have shown varying results regarding color shifts during eclipses.
Purpose of the Study:
- To measure the relative spectral intensity of the zenith sky during a total solar eclipse.
- To investigate potential color shifts in the zenith sky spectrum during an eclipse.
- To compare eclipse observations with established atmospheric scattering models.
Main Methods:
- Utilized an optical scanning spectrometer for spectral intensity measurements.
- Recorded data at Nantucket Island, Massachusetts, during the March 7, 1970, total solar eclipse.
- Calculated spectral ratios I(5100 A)/I(4300 A) and I(5900 A)/I(5100 A).
Main Results:
- Spectral ratios remained constant for up to 96% solar obscuration.
- A blue color shift was observed for solar elevation angles below 45 degrees, consistent with Rayleigh scattering.
- Inconsistent color shifts were noted for solar elevation angles above 45 degrees.
Conclusions:
- Zenith sky spectral intensity is stable during significant solar obscuration.
- Rayleigh scattering explains observed color shifts at lower solar elevation angles.
- Inconsistencies at higher solar angles may stem from challenges in selecting a reference spectrum.
More Related Videos
09:00Indoor Experimental Assessment of the Efficiency and Irradiance Spot of the Achromatic Doublet on Glass (ADG) Fresnel Lens for Concentrating Photovoltaics
Published on: October 27, 2017
07:51Method for Recording Broadband High Resolution Emission Spectra of Laboratory Lightning Arcs
Published on: August 27, 2019
Related Concept Videos
01:16Focusing of Light in the Eye
Light rays enter the eye through the cornea, a transparent dome-shaped tissue that is the eye's outermost layer. The cornea bends or refracts, light rays traveling to the pupil. The shape of the cornea determines how much of the light is bent and whether the image will be focused correctly on the retina at the back of the eye. Once the light has passed through both refraction layers, it converges into a single focal point onto a small area. This is where photoreceptors start transforming...
01:02Ultraviolet and Visible (UV–Vis) Spectroscopy: Overview
Ultraviolet–visible (UV–visible or UV–Vis) spectroscopy is an analytical technique that investigates the interaction between matter and UV–Vis light within the electromagnetic spectrum. This method is widely used for its versatility, simplicity, and relatively quick data acquisition, making it valuable for both qualitative and quantitative analysis. When UV–Vis radiation passes through a material, molecules absorb light depending on the energy required for electronic transitions. As a result...
02:39Emission Spectra
When solids, liquids, or condensed gases are heated sufficiently, they radiate some of the excess energy as light. Photons produced in this manner have a range of energies, and thereby produce a continuous spectrum in which an unbroken series of wavelengths is present.
01:05Total Internal Reflection Fluorescence Microscopy
Total internal reflection fluorescence microscopy or TIRF is an advanced microscopic technique used to visualize fluorophores in samples close to a solid surface with a higher refractive index, such as a glass coverslip. TIRF only allows fluorophores in proximity to the solid surface to be excited. When light from a medium with a lower refractive index (such as air) hits the glass coverslip at a critical angle, the light undergoes total internal reflection stead of passing through the glass.
01:14UV–Vis Spectrometers
The absorbance of UV and visible (UV–visible) radiations is measured using a UV–visible spectrophotometer. Deuterium lamps, which emit UV radiation, and tungsten lamps, which produce radiation in the visible region, are used as light sources in UV–visible spectrophotometers. A monochromator or prism is used for diffraction grating, i.e., to split the incoming radiation into different wavelengths. A system of slits is used to focus the desired wavelength on the sample cell. Samples for...
01:26Influence of Earth's Curvature and Atmospheric Refraction on Leveling
During leveling, the Earth's curvature and atmospheric refraction introduce deviations in the line of sight from a true horizontal reference. When the line of sight is leveled, it remains perpendicular to the plumb line only at a single point. Beyond this, it deviates due to the Earth’s curvature, represented by the correction C. For a sight distance D, the deviation can be derived using the relationship:This relationship shows that the deviation increases quadratically with distance. Over a...