scholarly journals ENERGY AND VISION

1921 ◽  
Vol 3 (6) ◽  
pp. 743-764 ◽  
Author(s):  
P. Lecomte du Noüy
Keyword(s):  
Water Vapor ◽  
Rock Salt ◽  
Wave Length ◽  
The Sun ◽  
Great Care ◽  
Earth’S Atmosphere ◽  
Reflected Light ◽  
Earth's Atmosphere ◽  
Different Parts ◽  
Good Agreement

A method was devised for measuring the minimum visibile in different parts of the spectrum, as done by Langley in 1888. The results are generally in good agreement with those given by this author, although not as close on both sides of the wave length 0.55 µ; this may be due partly to the use of a rock salt prism, to the fact that the minimum was determined by looking at a beam of diffused transmitted, instead of diffused reflected light, and also to the fact that Langley experimented with the sun, through the earth's atmosphere, and had to take into account the thickness of the atmosphere interposed and the brightness of the sky. Although his experiments were made with great care, the differences from one day to another are important. However, when he expresses the energy in absolute units, he always refers to the same mean amount of energy radiated by the sun on 1 sq. cm. This amount is certainly not constant, if one judges from the differences observed in two measurements of sensitivity of the eye of the same individual at different dates. On the contrary, for a given wave length, our measurements always agreed closely, as our source of radiation was very nearly constant, owing to the absence of a varying amount of water vapor interposed. This may in some way account for the discrepancies observed.

scholarly journals High-resolution spectroscopy and spectropolarimetry of the total lunar eclipse January 2019

2020 ◽  
Vol 635 ◽  
pp. A156
Author(s):  
K. G. Strassmeier ◽  
I. Ilyin ◽  
E. Keles ◽  
M. Mallonn ◽  
A. Järvinen ◽  
...  
Keyword(s):  
Large Scale ◽  
Solar Spectrum ◽  
High Resolution Spectroscopy ◽  
Strong Increase ◽  
Lunar Eclipse ◽  
The Sun ◽  
The Moon ◽  
Earth’S Atmosphere ◽  
The Earth ◽  
Earth's Atmosphere

Context. Observations of the Earthshine off the Moon allow for the unique opportunity to measure the large-scale Earth atmosphere. Another opportunity is realized during a total lunar eclipse which, if seen from the Moon, is like a transit of the Earth in front of the Sun. Aims. We thus aim at transmission spectroscopy of an Earth transit by tracing the solar spectrum during the total lunar eclipse of January 21, 2019. Methods. Time series spectra of the Tycho crater were taken with the Potsdam Echelle Polarimetric and Spectroscopic Instrument (PEPSI) at the Large Binocular Telescope in its polarimetric mode in Stokes IQUV at a spectral resolution of 130 000 (0.06 Å). In particular, the spectra cover the red parts of the optical spectrum between 7419–9067 Å. The spectrograph’s exposure meter was used to obtain a light curve of the lunar eclipse. Results. The brightness of the Moon dimmed by 10.m75 during umbral eclipse. We found both branches of the O2 A-band almost completely saturated as well as a strong increase of H2O absorption during totality. A pseudo O2 emission feature remained at a wavelength of 7618 Å, but it is actually only a residual from different P-branch and R-branch absorptions. It nevertheless traces the eclipse. The deep penumbral spectra show significant excess absorption from the Na I 5890-Å doublet, the Ca II infrared triplet around 8600 Å, and the K I line at 7699 Å in addition to several hyper-fine-structure lines of Mn I and even from Ba II. The detections of the latter two elements are likely due to an untypical solar center-to-limb effect rather than Earth’s atmosphere. The absorption in Ca II and K I remained visible throughout umbral eclipse. Our radial velocities trace a wavelength dependent Rossiter-McLaughlin effect of the Earth eclipsing the Sun as seen from the Tycho crater and thereby confirm earlier observations. A small continuum polarization of the O2 A-band of 0.12% during umbral eclipse was detected at 6.3σ. No line polarization of the O2 A-band, or any other spectral-line feature, is detected outside nor inside eclipse. It places an upper limit of ≈0.2% on the degree of line polarization during transmission through Earth’s atmosphere and magnetosphere.

XXXIX.—Did the Tail of Halley's Comet affect the Earth's Atmosphere?

1910 ◽  
Vol 30 ◽  
pp. 529-550
Author(s):  
John Aitken
Keyword(s):  
The Sun ◽  
Earth’S Atmosphere ◽  
Magnetic Condition ◽  
The Earth ◽  
Electrical Condition ◽  
Halley's Comet ◽  
Earth's Atmosphere ◽  
Pass Through

The return of Halley's Comet in May of this year gave rise to much speculation as to its possible effects on the earth. As it was expected that the earth would pass through the tail of the comet when the comet passed between us and the sun, many observations were arranged for in order to see if the tail, whatever it was composed of, had any effect on the earth or on its atmosphere. If the tail was composed of matter in any form, gaseous, or fine solid or liquid particles, then it seemed possible to get some evidence of its presence in the atmosphere; or if the tail was composed of electrons, then these would disturb the electrical condition of the atmosphere, and also the magnetic condition of the earth.

scholarly journals Absorption of solar radiation by water vapor, oxygen, and related collision pairs in the Earth's atmosphere

1998 ◽  
Vol 103 (D4) ◽  
pp. 3847-3858 ◽  
Author(s):  
S. Solomon ◽  
R. W. Portmann ◽  
R. W. Sanders ◽  
J. S. Daniel
Keyword(s):  
Water Vapor ◽  
Solar Radiation ◽  
Earth’S Atmosphere ◽  
Earth's Atmosphere

scholarly journals Exploring earth's atmosphere with radio occultation: contributions to weather, climate and space weather

2011 ◽  
Vol 4 (1) ◽  
pp. 135-212 ◽  
Author(s):  
R. A. Anthes
Keyword(s):  
Water Vapor ◽  
Electron Density ◽  
Space Weather ◽  
Radio Occultation ◽  
Proof Of Concept ◽  
Atmospheric Research ◽  
Earth’S Atmosphere ◽  
Satellite Constellation ◽  
Earth's Atmosphere ◽  
Satellite Missions

Abstract. The launch of the proof-of-concept mission GPS/MET in 1995 began a revolution in profiling earth's atmosphere through radio occultation (RO). GPS/MET; subsequent single-satellite missions CHAMP, SAC-C, GRACE, METOP-A, and TerraSAR-X; and the six-satellite constellation, FORMOSAT-3/COSMIC, have proven the theoretical capabilities of RO to provide accurate and precise profiles of electron density in the ionosphere and refractivity, containing information on temperature and water vapor, in the stratosphere and troposphere. This paper summarizes results from these RO missions and the applications of RO observations to atmospheric research and operational weather analysis and prediction.

A discussion on infared astronomy - Infrared solar spectrum as observed from balloons

1969 ◽  
Vol 264 (1150) ◽  
pp. 183-194 ◽  
Keyword(s):  
Spectral Data ◽  
Solar Spectrum ◽  
Wavelength Region ◽  
Primary Objective ◽  
Spectral Radiance ◽  
Atmospheric Effects ◽  
The Sun ◽  
Integration Technique ◽  
Earth’S Atmosphere ◽  
Good Agreement

The variation of the infrared solar spectrum in the region from 2.2 to 13 μm with altitude has been observed during a series of balloon flights. The primary objective of these flights has been to obtain data concerning the transmittance of the Earth’s atmosphere in this wavelength region particularly at altitudes from 13 to 31 km. The transmittance observed during these flights are compared with the transmittances calculated using a line-by-line integration technique. It is shown that it is possible to get good agreement between the observed and calculated results provided the distribution of the absorbing molecule is known. In addition to the flights during which only relative data were obtained, two flights were made during which absolute spectral data were obtained. From these data the spectral radiance of the Sun has been determined without the complication of correcting for atmospheric effects. The results are in good agreement with the results of other investigators in the wavelength regions where such measurements have been made from the ground.

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