Results 41 to 50 of about 12,606 (256)

Plasma Conditions Govern the Reversible Transition Between STEVE and Picket Fence Emissions

Geophysical Research Letters, Volume 53, Issue 2, 28 January 2026.
Abstract On 6 May 2018, a remarkable subauroral optical event exhibiting three phases of evolution (Strong Thermal Emission Velocity Enhancement [STEVE] → Picket Fence → STEVE) and co‐occurrence with a stable auroral red arc was observed over Alberta, Canada.
Jinghan Wang, Jing Liu, Jun Liang, Shuhan Li   +3 more
wiley   +1 more source

Scientific goals of optical instruments of the National Heliogeophysical Complex

Solar-Terrestrial Physics, 2020
Studies of the upper atmosphere have to be performed using optical photometric and spectrometric means. Modern devices allow precise photometry of the glow of the night atmosphere — airglow — with high temporal spatial and spectral resolution.
Vasilyev R.V., Artamonov M.F., Beletsky A.B., Zorkaltseva O.S., Komarova E.S., Medvedeva I.V., Mikhalev A.V., Podlesny S.V., Ratovsky K.G., Syrenova T.E., Tashchilin M.A., Tkachev I.D.   +11 more
doaj   +1 more source

The airglow layer emission altitude cannot be determined unambiguously from temperature comparison with lidars [PDF]

, 2018
I investigate the nightly mean emission height and width of the OH*(3-1) layer by comparing nightly mean temperatures measured by the ground-based spectrometer GRIPS 9 and the Na lidar at ALOMAR.
Dunker, Tim
core   +2 more sources

On the Energy Source of Green Emissions in Ghost

Geophysical Research Letters, Volume 53, Issue 2, 28 January 2026.
Abstract The understanding on the formation mechanism of ghosts as a new category of transient luminous events and favorable conditions for their occurrence is limited. In this work, we examined six ground‐based observations of ghost events captured by digital SLR cameras.
Xin Huang, Zhu Meng, Gaopeng Lu, Zhengwei Cheng, Feifan Liu, Ningyu Liu, Paul M. Smith, Frankie Lucena   +7 more
wiley   +1 more source

Automated Detection and Tracking of Equatorial Plasma Bubbles Utilizing Global‐Scale Observations of the Limb and Disk (GOLD) 135.6 nm Data

Earth and Space Science, 2023
Equatorial plasma bubbles (EPBs) are regions of depleted plasma within the ionosphere that form during post‐sunset hours near the magnetic equator. EPBs tend to align with local geomagnetic field lines, extend hundreds of kilometers along geomagnetic ...
V. J. Adkins, S. L. England
doaj   +1 more source

A Far-Ultraviolet Spectroscopic Survey of Luminous Cool Stars

, 2004
FUSE ultraviolet spectra of 8 giant and supergiant stars reveal that high temperature (3 X 10^5 K) atmospheres are common in luminous cool stars and extend across the color-magnitude diagram from Alpha Car (F0 II) to the cool giant Alpha Tau (K5 III ...
A. K. Dupree, A. Lobel, Barnes T. G., Doyle J. G., Hartman H., Hunsch M., Hunsch M., Hunsch M., J. L. Linsky, Johnson H. L., Kaufman V., Marilli E., P. R. Young, Perryman M. A. C., Reimers D., Reimers D., Rutten R. G. M., S. Redfield, Schaller G., Strassmeier K. G., T. B. Ake, Teriaca L.   +21 more
core   +1 more source

Final Calibration of the Berkeley Extreme and Far-Ultraviolet Spectrometer on the ORFEUS-SPAS I and II Missions [PDF]

, 2001
The Berkeley Extreme and Far-Ultraviolet Spectrometer (BEFS) flew as part of the ORFEUS telescope on the ORFEUS-SPAS I and II space-shuttle missions in 1993 and 1996, respectively.
Hurwitz M., Jean Dupuis, Mark Hurwitz, Marsh M. C., Napiwotzki R., Penston M. V., Vidal-Madjar A., W. Van Dyke Dixon   +7 more
core   +2 more sources

Nachtsicht ins All mit dem bloßen Auge: Sag mir, wie weit die Sterne steh'n

Physik in unserer Zeit, Volume 57, Issue 1, Page 32-40, January 2026.
Beim Blick in den Nachthimmel sehen wir ohne optische Hilfsmittel und abhängig von der lokalen Lichtverschmutzung viele Hundert bis maximal einige Tausend Sterne und auch einige Galaxien. Aber wie weit sind diese von uns entfernt? Und bis zu welchen maximalen Entfernungen können wir Objekte im Weltall mit dem bloßen Auge wahrnehmen?
Michael Vollmer
wiley   +1 more source

Daily Variability in the Terrestrial UV Airglow

Atmosphere, 2020
New capability for observing conditions in the upper atmosphere comes with the implementation of global ultraviolet (UV) imaging from geosynchronous orbit. Observed by the NASA GOLD mission, the emissions of atomic oxygen (OI) and molecular nitrogen (N2)
Thomas J. Immel, Richard W. Eastes, William E. McClintock, Steven B. Mende, Harald U. Frey, Colin Triplett, Scott L. England   +6 more
doaj   +1 more source

The night-sky at the Calar Alto Observatory [PDF]

, 2007
We present a characterization of the main properties of the night-sky at the Calar Alto observatory for the time period between 2004 and 2007. We use optical spectrophotometric data, photometric calibrated images taken in moonless observing periods ...
Burki G., D. Pérez‐Ramírez, Holmes R. W., Ingham M. F., J. Aceituno, J. Alves, Lane M., Leinert C., Pedani M., Rufener F., S. F. Sánchez, Smith F. G., Treanor P. J., Tug H., U. Thiele, Walker A., Walker A., Walker M. F.   +17 more
core   +3 more sources