GUVI Biblio





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Found 32 entries in the Bibliography.


Showing entries from 1 through 32


2018

Storm-time variations of atomic nitrogen 149.3 nm emission

Net radiances of atomic nitrogen emission line (N-149.3 nm) from the thermosphere are extracted from the FUV spectra observed by TIMED/GUVI on dayside at ...

Zhang, Y.; Paxton, L.J.; Morrison, D.; Schaefer, B.;

Published by: Journal of Atmospheric and Solar-Terrestrial Physics      Published on: 04/2018

YEAR: 2018     DOI: 10.1016/j.jastp.2018.01.023

2015

Remote Sensing of Earth\textquoterights Limb by TIMED/GUVI: Retrieval of thermospheric composition and temperature

The Global Ultraviolet Imager (GUVI) onboard the Thermosphere-Ionosphere-Mesosphere Energetics and Dynamics (TIMED) satellite senses far ultraviolet emissions from O and N2 in the thermosphere. Transformation of far ultraviolet radiances measured on the Earth limb into O, N2, and O2 number densities and temperature quantifies these responses and demonstrates the value of simultaneous altitude and geographic information. Composition and temperature variations are available from 2002 to 2007 ...

Meier, R.; Picone, J.; Drob, D.; Bishop, J.; Emmert, J.; Lean, J.; Stephan, A.; Strickland, D.; Christensen, A.; Paxton, L.; Morrison, D.; Kil, H.; Wolven, B.; Woods, Thomas; Crowley, G.; Gibson, S.;

Published by: Earth and Space Science      Published on: 01/2015

YEAR: 2015     DOI: 10.1002/2014EA000035

airglow and aurora; remote sensing; thermosphere: composition and chemistry; thermosphere: energy deposition

2014

Storm-time behaviors of O/N2 and NO variations

Algorithms have been developed to extract net nitric oxide (NO) radiances in the wavelength range of 172\textendash182\ nm from the dayside TIMED/GUVI spectrograph data and convert them to NO column density (100\textendash150\ km). The thermospheric O/N2 column density ratios (referenced from an altitude ~135\ km with a N2column density of 1017\ cm-2) are also obtained from the spectrograph data. The spatial resolution of the NO and O/N2 products a ...

Zhang, Y.; Paxton, L.J.; Morrison, D.; Marsh, D.; Kil, H.;

Published by: Journal of Atmospheric and Solar-Terrestrial Physics      Published on: 07/2014

YEAR: 2014     DOI: 10.1016/j.jastp.2014.04.003

geomagnetic storm; Thermospheric nitric oxide; Thermospheric O/N2 ratio

2013

Empirical relationship between electron precipitation and far-ultraviolet auroral emissions from DMSP observations

Auroral emissions observed in the far-ultraviolet wavelength range are compared with measurements of the coincident precipitating electrons and ions that produce the emissions in a large-scale correlative study. The auroral emissions and particle precipitation are observed with the Special Sensor Ultraviolet Spectrographic Imager and SSJ5 detectors, respectively, both onboard the DMSP F16 satellite. Coincident observations along the same magnetic field line in the Northern Hemisphere are assembled from two consecutive win ...

Sotirelis, Thomas; Korth, Haje; Hsieh, Syau-Yun; Zhang, Yongliang; Morrison, Daniel; Paxton, Larry;

Published by: Journal of Geophysical Research: Space Physics      Published on: 03/2013

YEAR: 2013     DOI: 10.1002/jgra.50157

DMSP; electron aurora; electron precipitation; FUV Aurora

2010

Auroral and thermospheric response to the 9 day periodic variations in the dayside reconnection rate in 2005

Zhang, Yongliang; Paxton, L.; Morrison, Daniel;

Published by: Space Weather      Published on: Jan-01-2010

YEAR: 2010     DOI: 10.1029/2009SW000559

2007

Constraining and validating the Oct/Nov 2003 X-class EUV flare enhancements with observations of FUV dayglow and E -region electron densities

Strickland, D.; Lean, J.; Daniell, R.; Knight, H.; Woo, W.; Meier, R.; Straus, P.; Woods, T.; Eparvier, F.; McMullin, D.; Christensen, A.; Morrison, D.; Paxton, L.;

Published by: Journal of Geophysical Research      Published on: Jan-01-2007

YEAR: 2007     DOI: 10.1029/2006JA012074

2006

Global thermosphere-ionosphere response to onset of 20 November 2003 magnetic storm

Crowley, G.; Hackert, C.; Meier, R.; Strickland, D.; Paxton, L.; Pi, X.; Mannucci, A.; Christensen, A.; Morrison, D.; Bust, G.; Roble, R.; Curtis, N.; Wene, G.;

Published by: Journal of Geophysical Research      Published on: Jan-01-2006

YEAR: 2006     DOI: 10.1029/2005JA011518

2005

First look at the 20 November 2003 superstorm with TIMED/GUVI: Comparisons with a thermospheric global circulation model

The NASA TIMED/GUVI experiment obtained unprecedented far ultraviolet images of thermospheric composition and temperature during the intense geomagnetic storm on 20\textendash21 November 2003. Geographic maps of the atomic oxygen to molecular nitrogen column density ratio show severe depletions that extend to the equator near the peak of the storm. This ratio is a key indicator of how the thermospheric composition is disrupted at high latitudes and how the perturbed air moves globally as a result of dynamical forcing. For ...

Meier, R.; Crowley, G.; Strickland, D.; Christensen, A.; Paxton, L.; Morrison, D.; Hackert, C.;

Published by: Journal of Geophysical Research      Published on: 09/2005

YEAR: 2005     DOI: 10.1029/2004JA010990

dayglow; geomagnetic storm; GUVI; remote sensing; thermospheric composition; TIMED

Undulations on the equatorward edge of the diffuse proton aurora: TIMED/GUVI observations

Undulations on the equatorward edge of the diffuse proton aurora have been identified by using TIMED/GUVI auroral images in the far ultraviolet wavelengths. While undulations have been previously reported on the duskside (Lui et al., 1982), GUVI observations show the undulation also occurs in the dayside, nightside, and morningside. The GUVI proton auroral images provide direct optical evidence that the undulations occur in the proton aurora. It is also the first detection of the undulation in the dayside indicating stron ...

Zhang, Y.; Paxton, L.; Morrison, D.; T. Y. Lui, A.; Kil, H.; Wolven, B.; Meng, C.-I.; Christensen, A.;

Published by: Journal of Geophysical Research      Published on: 09/2005

YEAR: 2005     DOI: 10.1029/2004JA010668

auroral undulation; K-H instability; Magnetic storm; plasma convection

E-Layer Variations During X-Class Flares Inferred from Far Ultraviolet Dayglow Observations

A study is reported that addresses dayglow and ionospheric response to X-class flares that occurred on Oct 28 and Nov 4 2003. Data of interest are 1) the dayglow observations by GUVI and solar EUV/X-ray observations by SEE (both on NASA\textquoterights TIMED satellite), 2) E-region measurements made by the EISCAT radar (on Oct 28) located at Troms\o, Norway, and 3) E-region/F-region IOX GPS occultation measurements (on Nov 4). The timing of the flares was fortunate in that TIMED was on the dayside portion of its orbit whe ...

Strickland, D.~J.; Daniell, R.~E.; Meier, R.~R.; Lean, J.~L.; Straus, P.~R.; Morrison, M.~D.; Paxton, L.;

Published by: AGU Fall Meeting Abstracts      Published on:

YEAR: 2005     DOI:

2479 Solar radiation and cosmic ray effects; 7519 Flares; 7549 Ultraviolet emissions; 7974 Solar effects

Far-ultraviolet signature of polar cusp during southward IMF Bz observed by TIMED/Global Ultraviolet Imager and DMSP

The coincident TIMED/Global Ultraviolet Imager (TIMED/GUVI) optical and DMSP particle observations have revealed new features of the optical signature of the polar cusp under a southward interplanetary magnetic field (IMF). We have found that cusp auroras usually take the shape of a thin arc with a width around 100\textendash200 km. This provides the first far-ultraviolet evidence of the narrow cusp under a southward IMF [

Zhang, Y; Meng, C-I; Paxton, LJ; Morrison, D; Wolven, B; Kil, H; Newell, P; Wing, S; Christensen, AB;

Published by: Journal of Geophysical Research: Space Physics (1978\textendash2012)      Published on:

YEAR: 2005     DOI: 10.1029/2004JA010707

cusp aurora

Global Thermosphere-Ionosphere Response to Geomagnetic Storms

Crowley, G.; Hackert, C.; Meier, R.; Strickland, D.; Paxton, L.; Pi, X.; Manucci, A.; Christensen, A.; Morrison, D.; Bust, G.; Roble, R.; Curtis, N.;

Published by:       Published on:

YEAR: 2005     DOI:

Imaging the Low-Latitude Ionosphere: Future Collaborations with C/NOFS

Paxton, L.; Kil, H.; DeMajistre, R.; Zhang, Y.; Morrison, D.; Wolven, B.; Meng, C.-I;

Published by:       Published on:

YEAR: 2005     DOI:

Nightside detached auroras due to precipitating protons/ions during intense magnetic storms

Nightside detached auroras (NDA) during intense magnetic storms are studied by using FUV image data from Thermosphere-Ionosphere-Mesosphere Energetics and Dynamics (TIMED)/Global Ultraviolet Imager (GUVI), Imager for Magnetopause-to-Aurora Global Exploration (IMAGE)/FUV, and particle data from DMSP/SSJ/4 instruments. We found that NDA are caused by proton/ion precipitation only. Thin arc-shaped NDA are very likely due to soft (\<1 keV) proton/ion precipitation. Thick or patch-shaped NDA are caused by energetic (\~10 ke ...

Zhang, Y; Paxton, LJ; Morrison, D; Wolven, B; Kil, H; Wing, S;

Published by: Journal of Geophysical Research: Space Physics (1978\textendash2012)      Published on:

YEAR: 2005     DOI: 10.1029/2004JA010498

detached aurora; proton precipitation; ring current; Magnetic storm

TIMED/GUVI Observations of the Ionosphere and Thermosphere Interaction

Paxton, L.; Kil, H.; DeMajistre, R.; Zhang, Y.; Morrison, D.; Wolven, B.; Meng, C.-I.;

Published by: Ann. Geophys., special ISEA      Published on:

YEAR: 2005     DOI:

2004

Coincident equatorial bubble detection by TIMED/GUVI and ROCSAT-1

Kil, Hyosub; Su, S.-Y.; Paxton, L.; Wolven, B.; Zhang, Y.; Morrison, D.; Yeh, H.;

Published by: Geophysical Research Letters      Published on: Jan-01-2004

YEAR: 2004     DOI: 10.1029/2003GL018696

O/N 2 changes during 1\textendash4 October 2002 storms: IMAGE SI-13 and TIMED/GUVI observations

Thermospheric O/N2 column density ratios referenced at a N2 column density of 1017 cm-2 are obtained using the IMAGE SI-13 and TIMED/GUVI far-ultraviolet (FUV) dayglow data, AURIC simulation results, and MSIS86 model. Each of the magnetic storms occurring during a 4-day period (1\textendash4 October 2002) caused significant O/N2 depletion that was detected by both of the IMAGE SI-13 and GUVI instruments. The depletion extended down to latitudes of 10\textdegree and -5 ...

Zhang, Y.; Paxton, L.; Morrison, D.; Wolven, B.; Kil, H.; Meng, C.-I.; Mende, S.; Immel, T.;

Published by: Journal of Geophysical Research      Published on: 10/2004

YEAR: 2004     DOI: 10.1029/2004JA010441

Magnetic storm; thermospheric composition change

Double dayside detached auroras: TIMED/GUVI observations

On August 19, 2003, TIMED/GUVI detected, for the first time, two separated (double) dayside detached auroras (D-DDA) simultaneously in all the GUVI channels, 121.6 nm, 135.6 nm, LBHS, and LBHL. The D-DDA was located at magnetic latitudes around -57\textdegree and -63\textdegree (L shell 3.4 and 4.9) in the 0900\textendash1030 MLT region. The high-latitude part of the D-DDA is much brighter than the low-latitude part. DMSP particle observation indicates that the source of the D-DDA is energetic (\~10 keV) precipitating pro ...

Zhang, Y.; Paxton, L.; Meng, C.-I.; Morrison, D.; Wolven, B.; Kil, H.; Christensen, A.;

Published by: Geophysical Research Letters      Published on: 05/2004

YEAR: 2004     DOI: 10.1029/2003GL018949

Height-integrated Joule and auroral particle heating in the night side high latitude thermosphere

Energy deposited at high latitudes by Joule and auroral particle heating perturbs the chemistry and dynamics of the neutral thermosphere. Height-integrated heating rates can be calculated by combining Super Dual Auroral Radar Network (SuperDARN) measurements with TIMED spacecraft Global Ultraviolet Imager (GUVI) auroral images. Spatial maps of heating rates are examined during two TIMED orbits and statistical averages are presented for quiet to moderate levels of geomagnetic activity. Joule heating dominates in the evenin ...

Baker, JBH; Zhang, Y; Greenwald, RA; Paxton, LJ; Morrison, D;

Published by: Geophysical research letters      Published on: 05/2004

YEAR: 2004     DOI: 10.1029/2004GL019535

Retrievals of nighttime electron density from Thermosphere Ionosphere Mesosphere Energetics and Dynamics (TIMED) mission Global Ultraviolet Imager (GUVI) measurements

In this work we will present a method for retrieving nighttime electron density profiles from OI 135.6 nm limb emissions measured by the Global Ultraviolet Imager (GUVI) aboard the Thermosphere Ionosphere Mesosphere Energetics and Dynamics (TIMED) mission spacecraft. The primary mechanism for 135.6 nm radiance in the nighttime thermosphere is recombination of O+ ions, and the volume emission rate is approximately proportional to the square of the electron density. Herein we describe a two-step inversion method ...

DeMajistre, R.; Paxton, L.; Morrison, D.; Yee, J.-H.; Goncharenko, L.; Christensen, A.;

Published by: Journal of Geophysical Research      Published on: 04/2004

YEAR: 2004     DOI: 10.1029/2003JA010296

Electron density; inversion; low-latitude ionosphere; TIMED/GUVI

Quiet-time seasonal behavior of the thermosphere seen in the far ultraviolet dayglow

The TIMED/GUVI instrument is a far ultraviolet spectrograph that obtains images in five spectrally resolved wavelength channels. These images yield information on the dayside composition, temperature, solar EUV flux, large-scale wave structures, and auroral processes. In this paper we present an overview analysis of Earth-disk images for four seasons (March, July, and September 2002 and January 2003). Days were selected during geomagnetically quiet periods when the Sun was nearly in the orbital plane (noon orbits). Two of ...

Strickland, D.; Meier, R.; Walterscheid, R.; Christensen, A.; Paxton, L.; Morrison, D.; Craven, J.; Crowley, G.;

Published by: Journal of Geophysical Research      Published on: 01/2004

YEAR: 2004     DOI: 10.1029/2003JA010220

far ultraviolet; remote sensing; seasonal behavior; thermosphere

GUVI: a hyperspectral imager for geospace

The Global Ultraviolet Imager (GUVI) is an imaging spectrometer on the NASA TIMED spacecraft which was launched on December 7, 2001. This instrument produces a far ultraviolet (FUV) data cube of spatial and spectral information at each step of a scan mirror - that scan mirror covers 140 deg in the cross track direction - a span that includes on limb. GUVI produces simultaneous monochromatic images at five "colors" (121.6 nm, 130.4 nm, 135.6 nm, and in broader bands at 140-150 nm and 165-180 nm) as its field of view is sca ...

Paxton, L.; Christensen, Andrew; Morrison, Daniel; Wolven, Brian; Kil, Hyosub; Zhang, Yongliang; Ogorzalek, Bernard; Humm, David; Goldsten, John; DeMajistre, Robert; Meng, Ching-I.;

Published by:       Published on:

YEAR: 2004     DOI: 10.1117/12.579171

Solar EUV irradiance variability derived from terrestrial far ultraviolet dayglow observations

Remotely sensed ultraviolet emissions from the Earth's upper atmosphere are shown to mirror fluctuations in solar EUV irradiance during July 2002, including the overall increase and decrease as the Sun rotated, and episodic increases associated with multiple solar flares. The TIMED/GUVI dayglow observations are used to derive a new quantity, QEUVGUVI, which is a measure of integrated solar EUV electromagnetic energy shortward of 45 nm. Both the absolute QEUVGUVI values and their modulation by solar rotation agree well with ...

Strickland, D.J.; Lean, J.L.; Meier, R.R.; Christensen, A.B.; Paxton, L.J.; Morrison, D.; Craven, J.D.; Walterscheid, R.L.; Judge, D.L.; McMullin, D.R.;

Published by: Geophysical research letters      Published on:

YEAR: 2004     DOI: 10.1029/2003GL018415

2003

The use of far ultraviolet remote sensing to monitor space weather

This paper discusses the connection between changes in Earth\textquoterights thermosphere and ionosphere induced by changes in the Earth\textquoterights local space environment (or \textquotedblleftspace weather\textquotedblright) and the phenomena observed in far ultraviolet images of the Earth. Two new experiments, the Global Ultraviolet Imager (GUVI) and the Special Sensor Ultraviolet Imager (SSUSI), will provide a new capability for monitoring changes in thermospheric composition and ionospheric density as they change ...

Paxton, L.; Morrison, Daniel; Strickland, Douglas; McHarg, M.Geoff; Zhang, Yongliang; Wolven, Brian; Kill, Hyosub; Crowley, Geoff; Christensen, Andrew; Meng, Ching-I;

Published by: Advances in Space Research      Published on: Jan-01-2003

YEAR: 2003     DOI: 10.1016/S0273-1177(02)00886-4

Initial observations with the Global Ultraviolet Imager (GUVI) in the NASA TIMED satellite mission

The Global Ultraviolet Imager (GUVI) instrument carried aboard the NASA TIMED satellite measures the spectral radiance of the Earth\textquoterights far ultraviolet airglow in the spectral region from 120 to 180 nm using a cross-track scanning spectrometer design. Continuous operation of the instrument provides images of the Earth\textquoterights disk and limb in five selectable spectral bands. Also, spectra at fixed scanning mirror position can be obtained. Initial results demonstrate the quantitative functionality of the ...

Christensen, AB; Paxton, LJ; Avery, S; Craven, J; Crowley, G; Humm, DC; Kil, H; Meier, RR; Meng, C-I; Morrison, D; , others;

Published by: Journal of Geophysical Research: Space Physics (1978\textendash2012)      Published on:

YEAR: 2003     DOI: 10.1029/2003JA009918

airglow; AURORA; ultraviolet; imaging; satellite; atmosphere

Optical Signature of Polar Cusp During Southward IMF Bz Observed by TIMED/GUVI and DMSP

The GUVI instrument on board the TIMED satellite provides unique multi-wavelength observations of polar region emissions. In this study we focus on the identification of the polar cusp region during southward IMF conditions. Using simultaneous DMSP particle observations, the optical signatures and dynamics of the polar cusp region are investigated. We will address which of the five GUVI wavelengths can best be used for optical identification of the cusp precipitation by comparing images of various wavelengths. These new G ...

Zhang, Y.; Meng, C.~I.; Paxton, L.~J.; Morrison, D.; Wolven, B.; Kil, H.; Newell, P.; Wing, S.; Christensen, A.~B.;

Published by: AGU Fall Meeting Abstracts      Published on:

YEAR: 2003     DOI:

2455 Particle precipitation; 2704 Auroral phenomena (2407); 2724 Magnetopause; and boundary layers; cusp

2002

Validation of remote sensing products produced by the Special Sensor Ultraviolet Scanning Imager (SSUSI): a far UV-imaging spectrograph on DMSP F-16

Operational sensors are designed and intended to reliably produce the measurements needed to develop high-value key environmental parameters. The Special Sensor Ultraviolet Spectrographic Imager (SSUSI) is slated to fly on the next five Defense Meteorological Satellite Program launches (beginning with the launch of F16 in Fall 2001). SSUSI will routinely produce maps of ionospheric and upper atmospheric composition and image the aurora. In this paper we describe these products and our validation plans and the process thro ...

Paxton, L.J.; Morrison, Daniel; Zhang, Yongliang; Kil, Hyosub; Wolven, Brian; Ogorzalek, Bernard; Humm, David; Meng, Ching-I.;

Published by:       Published on:

YEAR: 2002     DOI: 10.1117/12.454268

Remote sensing of the nighttime ionosphere with the TIMED Global Ultraviolet Imager

The Global Ultraviolet Imager (GUVI) aboard the TIMED spacecraft monitors ultraviolet radiation from the terrestrial atmosphere in five spectral regions. Measurements of 1356-angstrom radiation on the Earth\textquoterights limb are part of this dataset. The primary source of this 1356-angstrom radiation on the night side is the recombination of molecular oxygen ions and electrons. In this work, we present a method for inferring vertical electron density profiles and total electron content (TEC) from the GUVI night-side li ...

DeMajistre, R.; Talaat, E.; Kil, H.; Zhang, Y.; Paxton, L.; Morrison, D.; Wolven, B.; Meng, C.-I.; Christensen, A.;

Published by:       Published on:

YEAR: 2002     DOI:

On-orbit calibration of the Special Sensor Ultraviolet Scanning Imager (SSUSI): a far-UV imaging spectrograph on DMSP F-16

The Special Sensor Ultraviolet Spectrographic Imager (SSUSI) is currently slated for launch on the Defense Meteorological Satellite Program (DMSP) F-16 in November 2001. This instrument consists of a scanning imaging spectrograph (SIS) whose field-of-view is scanned from horizon-to-horizon and a nadir-looking photometer system (NPS). It will provide operational information about the state of the atmosphere above 100 km. The unique problems incurred by the observational requirements (e.g. that we be able to make daytime an ...

Morrison, D.; Paxton, L.J.; Humm, D.~C.; Wolven, B.; Kil, H.; Zhang, Y.; Ogorzalek, B.~S.; Meng, C.-I.;

Published by:       Published on:

YEAR: 2002     DOI:

2000

The Use of Far Ultraviolet Remote Sensing to Monitor Space Weather

Paxton, L.; Morrison, D.; Strickland, D.; McHarg, M.; Zhang, Y.; Wolven, B.; Kil, H.; Crowley, G.; Christensen, A.; Meng, C.-I;

Published by: COSPAR Adv. Space Research      Published on:

YEAR: 2000     DOI:

1999

Global ultraviolet imager (GUVI): measuring composition and energy inputs for the NASA Thermosphere Ionosphere Mesosphere Energetics and Dynamics (TIMED) mission

The Global Ultraviolet Imager (GUVI) on the NASA Thermosphere Ionosphere Mesosphere Energetics and Dynamics (TIMED) mission will determine the variability in thermospheric composition, and its response to auroral inputs as well as measuring those inputs. GUVI is the result of twenty years of work in designing large field of regard far ultraviolet (110 - 180 nm) imagers for spaceflight. These systems are based on the concept of a horizon-to-horizon \textquoterightmonochromatic\textquoteright imager. The field of view of a ...

Paxton, L.J.; Christensen, A.~B.; Humm, D.~C.; Ogorzalek, B.~S.; Pardoe, C.~T.; Morrison, D.; Weiss, M.~B.; Crain, W.; Lew, P.~H.; Mabry, D.~J.; Goldsten, J.~O.; Gary, S.~A.; Persons, D.~F.; Harold, M.~J.; Alvarez, E.~B.; Ercol, C.~J.; Strickland, D.~J.; Meng, C.-I.;

Published by:       Published on:

YEAR: 1999     DOI:

1998

Design and performance of the Global Ultraviolet Imager (GUVI)

The Global UV imager (GUVI) is an imaging spectrometer on the NASA TIMED spacecraft. GUVI produces simultaneous monochromatic images at five \textquoterightcolors\textquoteright as its field of view is scanned from horizon to horizon. The instrument consists of a scan mirror feeding a parabolic telescope and Rowland circle spectrometer, with a wedge-and-strip detector at the focal plane. We describe the design, and give an overview of the environmental parameters that will be measured. GUVI is a modified version of the Sp ...

Humm, D.~C.; Paxton, L.J.; Christensen, A.~B.; Ogorzalek, B.~S.; Pardoe, C.~T.; Meng, C.-I.; Morrison, D.; Strickland, D.~J.; Evans, J.~S.; Weiss, M.~B.; Crain, W.; Lew, P.~H.; Mabry, D.~J.; Goldsten, J.~O.; Gary, S.~A.; Peacock, K.; Persons, D.~F.; Harold, M.~J.; Alvarez, E.~B.; Ercol, C.~J.;

Published by:       Published on:

YEAR: 1998     DOI:



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