Imaging Spectroscopy - Revision history

JimL at 20:02, 12 July 2021

2021-07-12T20:02:43Z

← Older revision		Revision as of 21:02, 12 July 2021
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	In imaging spectroscopy, a ~~photograph is taken in a way that~~ measures the intensity of light at ~~a number of~~ different wavelengths. ~~This process generates a separate light spectrum for~~ every pixel in the photograph.		Regular cameras record light intensity at 3 wavelengths (red, green, and blue), which is sufficient to produce an image the looks accurate to the human eye. In imaging spectroscopy, a camera measures the intensity of light at more than just 3 different wavelengths. For every pixel in the photograph, the camera records data that can be viewed as a graph showing how the intensity of light varies across the visible region of the electromagnetic spectrum (and sometimes beyond the visible region). That graph can reveal details about the chemical makeup and physical properties of the photographed object.

	Imaging spectroscopy ~~can be~~ used by telescopes and spacecraft to study Mars.		Imaging spectroscopy has been used by telescopes and spacecraft to study Mars.

	Reflectance spectroscopy and thermal emission spectroscopy are two types of imaging spectroscopy.		Reflectance spectroscopy and thermal emission spectroscopy are two types of imaging spectroscopy.

	==Reflectance Spectroscopy==		==Reflectance Spectroscopy==
	Reflectance spectroscopy measures the visible and infrared light spectrum of the sunlight reflected from an object. After the spectrum of the light emitted by the sun is taken into account, a spectrum that is specific to the reflecting material is calculated. This spectrum can be compared to a library of known spectra.<ref>Shaw GA & Burke HK. 2003. Spectral Imaging for Remote Sensing. Lincoln Laboratory Journal, 14(1), 3-28. <nowiki>https://courses.cs.washington.edu/courses/cse591n/07sp/papers/Shaw2003.pdf</nowiki></ref> The Compact Reconnaissance Imaging Spectrometer for Mars, an instrument on the [[Mars Reconnaissance Orbiter]], uses reflectance spectroscopy to ~~identify minerals on~~ the surface ~~of Mars~~.<ref>Johns Hopkins Applied Physics Laboratory. ~~Compact Reconnaissance Imaging Spectrometer for Mars~~. <nowiki>http://crism.jhuapl.edu/index.php</nowiki></ref>		Reflectance spectroscopy measures the visible and infrared light spectrum of the sunlight reflected from an object. After the spectrum of the light emitted by the sun is taken into account, a spectrum that is specific to the reflecting material is calculated. This spectrum can be compared to a library of known spectra.<ref>Shaw GA & Burke HK. 2003. Spectral Imaging for Remote Sensing. Lincoln Laboratory Journal, 14(1), 3-28. <nowiki>https://courses.cs.washington.edu/courses/cse591n/07sp/papers/Shaw2003.pdf</nowiki></ref> The [[Mars Express]] Orbiter uses an imaging spectrometer named Observatoire pour la Minéralogie, l'Eau, les Glaces et l'Activité (OMEGA) to study the elements and minerals present on the surface of Mars.<ref>The European Space Agency. Mars Express orbiter instruments. <nowiki>http://www.esa.int/Science_Exploration/Space_Science/Mars_Express/Mars_Express_instruments</nowiki></ref> OMEGA's detection of hydrated minerals in 2005 was, at the time, the strongest evidence that surface water was once present in large amounts and for a long duration.<ref>The European Space Agency. September 1 2019. Mars Express science highlights: #1. Hydrated minerals – evidence of liquid water on Mars. <nowiki>https://sci.esa.int/web/mars-express/-/51821-1-hydrated-minerals-ndash-evidence-of-liquid-water-on-mars</nowiki></ref> The Compact Reconnaissance Imaging Spectrometer for Mars, an instrument on the [[Mars Reconnaissance Orbiter]], uses reflectance spectroscopy to examine the surface and dust in the atmosphere. Among other findings, it was used to better understand how dust warms the Martian atmosphere by absorbing sunlight.<ref>Johns Hopkins Applied Physics Laboratory. CRISM's Investigations and New Discoveries (2006-present). <nowiki>http://crism.jhuapl.edu/science/themes/index.php</nowiki></ref>

	== Thermal Emission Spectroscopy ==		==Thermal Emission Spectroscopy==
	Thermal emission spectroscopy, also known as infrared imaging, measures the infrared light that is released by any object as a result of normal molecular vibrations. The spectrum of this light provides information on the composition of the object that emitted it, and that object's temperature. The Thermal Emission Spectrometer on [[Mars Global Surveyor]] used thermal emission spectroscopy to learn about dust in the Martian atmosphere and the surface temperature on Mars.<ref>Arizona State University. Mars Global Surveyor Thermal Emission Spectrometer. <nowiki>http://tes.asu.edu/index.html</nowiki></ref> The Thermal Infrared Imaging Spectrometer on the [[Mars Orbiter Mission]] spacecraft also uses this technique.<ref>Indian Space Research Organization. Payloads. In ''PSLV-C25/Mars Orbiter Mission''. <nowiki>https://www.isro.gov.in/pslv-c25-mars-orbiter-mission/payloads</nowiki></ref>		Thermal emission spectroscopy, also known as infrared imaging, measures the infrared light that is released by any object as a result of normal molecular vibrations. The spectrum of this light provides information on the composition of the object that emitted it, and that object's temperature. The Thermal Emission Spectrometer on [[Mars Global Surveyor]] used thermal emission spectroscopy to learn about dust in the Martian atmosphere and the surface temperature on Mars.<ref>Arizona State University. Mars Global Surveyor Thermal Emission Spectrometer. <nowiki>http://tes.asu.edu/index.html</nowiki></ref> The Thermal Infrared Imaging Spectrometer on the [[Mars Orbiter Mission]] spacecraft also uses this technique.<ref>Indian Space Research Organization. Payloads. In ''PSLV-C25/Mars Orbiter Mission''. <nowiki>https://www.isro.gov.in/pslv-c25-mars-orbiter-mission/payloads</nowiki></ref>
			==Multispectral Imaging==
			It is also possible for a single instrument to combine both of the above methods to perform multispectral imaging. The Thermal Emission Imaging System on [[Mars Odyssey]] is capable of multispectral imaging.<ref>Arizona State University School of Earth & Space Exploration. Frequently Asked Questions. In ''Mars Odyssey THEMIS''. <nowiki>http://themis.asu.edu/faq</nowiki></ref>

	== ~~Multispectral Imaging~~ ==		==External Links==
	~~It is also possible~~ for ~~a single instrument to combine both of the above methods to perform multispectral imaging. The Thermal Emission Imaging System on [[~~Mars ~~Odyssey]] is capable of multispectral imaging.<ref>Arizona State University School of Earth & Space Exploration. Frequently Asked Questions. In ''Mars Odyssey THEMIS''. <nowiki>~~http://~~themis~~.~~asu~~.edu/~~faq</nowiki></ref>~~		Compact Reconnaissance Imaging Spectrometer for Mars web site: http://crism.jhuapl.edu/index.php

	~~== External Links ==~~
	Library of thermal infrared spectra maintained by Arizona State University's Mars Space Flight Facility: https://speclib.asu.edu/		Library of thermal infrared spectra maintained by Arizona State University's Mars Space Flight Facility: https://speclib.asu.edu/

	==References==		==References==
	<references />		<references />

JimL at 23:32, 22 February 2021

2021-02-22T23:32:09Z

← Older revision		Revision as of 00:32, 23 February 2021
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	Imaging spectroscopy can be used by telescopes and spacecraft to study Mars.		Imaging spectroscopy can be used by telescopes and spacecraft to study Mars.

	Reflectance spectroscopy and emission spectroscopy are two types of imaging spectroscopy.		Reflectance spectroscopy and thermal emission spectroscopy are two types of imaging spectroscopy.

	==Reflectance Spectroscopy==		==Reflectance Spectroscopy==
	Reflectance spectroscopy measures the visible and infrared light spectrum of the sunlight reflected from an object. After the spectrum of the light emitted by the sun is taken into account, a spectrum that is specific to the reflecting material is calculated. This spectrum can be compared to a library of known spectra.<ref>Shaw GA & Burke HK. 2003. Spectral Imaging for Remote Sensing. Lincoln Laboratory Journal, 14(1), 3-28. <nowiki>https://courses.cs.washington.edu/courses/cse591n/07sp/papers/Shaw2003.pdf</nowiki></ref> The Compact Reconnaissance Imaging Spectrometer for Mars, an instrument on the [[Mars Reconnaissance Orbiter]], uses reflectance spectroscopy to identify minerals on the surface of Mars.<ref>Johns Hopkins Applied Physics Laboratory. Compact Reconnaissance Imaging Spectrometer for Mars. <nowiki>http://crism.jhuapl.edu/index.php</nowiki></ref>		Reflectance spectroscopy measures the visible and infrared light spectrum of the sunlight reflected from an object. After the spectrum of the light emitted by the sun is taken into account, a spectrum that is specific to the reflecting material is calculated. This spectrum can be compared to a library of known spectra.<ref>Shaw GA & Burke HK. 2003. Spectral Imaging for Remote Sensing. Lincoln Laboratory Journal, 14(1), 3-28. <nowiki>https://courses.cs.washington.edu/courses/cse591n/07sp/papers/Shaw2003.pdf</nowiki></ref> The Compact Reconnaissance Imaging Spectrometer for Mars, an instrument on the [[Mars Reconnaissance Orbiter]], uses reflectance spectroscopy to identify minerals on the surface of Mars.<ref>Johns Hopkins Applied Physics Laboratory. Compact Reconnaissance Imaging Spectrometer for Mars. <nowiki>http://crism.jhuapl.edu/index.php</nowiki></ref>

	==Emission Spectroscopy==		== Thermal Emission Spectroscopy ==
	~~Emission~~ spectroscopy measures the infrared light that is released by any object as a result of normal molecular vibrations. The spectrum of this light provides information on the composition of the object that emitted it, and that object's temperature. The Thermal Emission Spectrometer on ~~the~~ [[Mars Global Surveyor]] used ~~this technique~~ to learn about dust in the Martian atmosphere and the surface temperature on Mars.<ref>Arizona State University. Mars Global Surveyor Thermal Emission Spectrometer. <nowiki>http://tes.asu.edu/index.html</nowiki></ref>		Thermal emission spectroscopy, also known as infrared imaging, measures the infrared light that is released by any object as a result of normal molecular vibrations. The spectrum of this light provides information on the composition of the object that emitted it, and that object's temperature. The Thermal Emission Spectrometer on [[Mars Global Surveyor]] used thermal emission spectroscopy to learn about dust in the Martian atmosphere and the surface temperature on Mars.<ref>Arizona State University. Mars Global Surveyor Thermal Emission Spectrometer. <nowiki>http://tes.asu.edu/index.html</nowiki></ref> The Thermal Infrared Imaging Spectrometer on the [[Mars Orbiter Mission]] spacecraft also uses this technique.<ref>Indian Space Research Organization. Payloads. In ''PSLV-C25/Mars Orbiter Mission''. <nowiki>https://www.isro.gov.in/pslv-c25-mars-orbiter-mission/payloads</nowiki></ref>

	== References ==		== Multispectral Imaging ==
			It is also possible for a single instrument to combine both of the above methods to perform multispectral imaging. The Thermal Emission Imaging System on [[Mars Odyssey]] is capable of multispectral imaging.<ref>Arizona State University School of Earth & Space Exploration. Frequently Asked Questions. In ''Mars Odyssey THEMIS''. <nowiki>http://themis.asu.edu/faq</nowiki></ref>

			== External Links ==
			Library of thermal infrared spectra maintained by Arizona State University's Mars Space Flight Facility: https://speclib.asu.edu/

			==References==
	<references />		<references />

JimL at 23:39, 10 November 2020

2020-11-10T23:39:36Z

← Older revision		Revision as of 00:39, 11 November 2020
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	Reflectance spectroscopy and emission spectroscopy are two types of imaging spectroscopy.		Reflectance spectroscopy and emission spectroscopy are two types of imaging spectroscopy.

	== Reflectance Spectroscopy ==		==Reflectance Spectroscopy==
	Reflectance spectroscopy measures the visible and infrared light spectrum of the sunlight reflected from an object. After the spectrum of the light emitted by the sun is taken into account, a spectrum that is specific to the reflecting material is calculated. This spectrum can be compared to a library of known spectra.<ref>Shaw GA & Burke HK. 2003. Spectral Imaging for Remote Sensing. Lincoln Laboratory Journal, 14(1), 3-28. <nowiki>https://courses.cs.washington.edu/courses/cse591n/07sp/papers/Shaw2003.pdf</nowiki></ref> The Compact Reconnaissance Imaging Spectrometer for Mars, an instrument on the [[Mars Reconnaissance Orbiter]], uses reflectance spectroscopy to identify minerals on the surface of Mars.<ref>Johns Hopkins Applied Physics Laboratory. Compact Reconnaissance Imaging Spectrometer for Mars. <nowiki>http://crism.jhuapl.edu/index.php</nowiki></ref>		Reflectance spectroscopy measures the visible and infrared light spectrum of the sunlight reflected from an object. After the spectrum of the light emitted by the sun is taken into account, a spectrum that is specific to the reflecting material is calculated. This spectrum can be compared to a library of known spectra.<ref>Shaw GA & Burke HK. 2003. Spectral Imaging for Remote Sensing. Lincoln Laboratory Journal, 14(1), 3-28. <nowiki>https://courses.cs.washington.edu/courses/cse591n/07sp/papers/Shaw2003.pdf</nowiki></ref> The Compact Reconnaissance Imaging Spectrometer for Mars, an instrument on the [[Mars Reconnaissance Orbiter]], uses reflectance spectroscopy to identify minerals on the surface of Mars.<ref>Johns Hopkins Applied Physics Laboratory. Compact Reconnaissance Imaging Spectrometer for Mars. <nowiki>http://crism.jhuapl.edu/index.php</nowiki></ref>

	== Emission Spectroscopy ==		==Emission Spectroscopy==
	Emission spectroscopy measures the infrared light that is released by any object as a result of normal molecular vibrations. The spectrum of this light provides information on the composition of the object that emitted it, and that object's temperature. The Thermal Emission Spectrometer on the [[Mars Global Surveyor]] used this technique to learn about dust in the Martian atmosphere and the surface temperature on Mars.<ref>Arizona State University. Mars Global Surveyor Thermal Emission Spectrometer. <nowiki>http://tes.asu.edu/index.html</nowiki></ref>		Emission spectroscopy measures the infrared light that is released by any object as a result of normal molecular vibrations. The spectrum of this light provides information on the composition of the object that emitted it, and that object's temperature. The Thermal Emission Spectrometer on the [[Mars Global Surveyor]] used this technique to learn about dust in the Martian atmosphere and the surface temperature on Mars.<ref>Arizona State University. Mars Global Surveyor Thermal Emission Spectrometer. <nowiki>http://tes.asu.edu/index.html</nowiki></ref>

			== References ==
			<references />

JimL: Created page with "In imaging spectroscopy, a photograph is taken in a way that measures the intensity of light at a number of different wavelengths. This process generates a separate light spe..."

2020-11-10T23:38:50Z

Created page with "In imaging spectroscopy, a photograph is taken in a way that measures the intensity of light at a number of different wavelengths. This process generates a separate light spe..."

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In imaging spectroscopy, a photograph is taken in a way that measures the intensity of light at a number of different wavelengths. This process generates a separate light spectrum for every pixel in the photograph.

Imaging spectroscopy can be used by telescopes and spacecraft to study Mars.

Reflectance spectroscopy and emission spectroscopy are two types of imaging spectroscopy.

== Reflectance Spectroscopy ==
Reflectance spectroscopy measures the visible and infrared light spectrum of the sunlight reflected from an object. After the spectrum of the light emitted by the sun is taken into account, a spectrum that is specific to the reflecting material is calculated. This spectrum can be compared to a library of known spectra.<ref>Shaw GA & Burke HK. 2003. Spectral Imaging for Remote Sensing. Lincoln Laboratory Journal, 14(1), 3-28. <nowiki>https://courses.cs.washington.edu/courses/cse591n/07sp/papers/Shaw2003.pdf</nowiki></ref> The Compact Reconnaissance Imaging Spectrometer for Mars, an instrument on the [[Mars Reconnaissance Orbiter]], uses reflectance spectroscopy to identify minerals on the surface of Mars.<ref>Johns Hopkins Applied Physics Laboratory. Compact Reconnaissance Imaging Spectrometer for Mars. <nowiki>http://crism.jhuapl.edu/index.php</nowiki></ref>

== Emission Spectroscopy ==
Emission spectroscopy measures the infrared light that is released by any object as a result of normal molecular vibrations. The spectrum of this light provides information on the composition of the object that emitted it, and that object's temperature. The Thermal Emission Spectrometer on the [[Mars Global Surveyor]] used this technique to learn about dust in the Martian atmosphere and the surface temperature on Mars.<ref>Arizona State University. Mars Global Surveyor Thermal Emission Spectrometer. <nowiki>http://tes.asu.edu/index.html</nowiki></ref>