Results 61 to 70 of about 5,560 (224)

Discovery and Initial Investigation of a New Low Surface Brightness Planetary Nebula Candidate at High Galactic Latitude

Astronomische Nachrichten, Volume 347, Issue 3, March 2026.
ABSTRACT Planetary nebulae represent a late evolutionary phase of low‐ to intermediate‐mass stars. In this article, we present the serendipitous discovery of a previously unknown, faint potential Galactic planetary nebula (PN) in the constellation Camelopardalis, identified during a survey‐inspection, aiming at the detection of dwarf companions of the ...
W. E. Celnik, P. Köchling, S. Kotov, J. Kozok, Y. Galata, L. Magrini, A. Moiseev, M. Nischang, C. Reese, P. Remmel, P. Riepe, T. Zilch, K. Werner   +12 more
wiley   +1 more source

Towards a Measurement of the Primordial Helium Isotope Ratio

The Astrophysical Journal
We report the discovery of two metastable neutral helium (He I *) absorbers in the Milky Way, and use the upgraded CRyogenic InfraRed Echelle Spectrograph (or CRIRES) on the Very Large Telescope to determine the helium isotope ratio, ^3 He/ ^4 He, along ...
Ryan J. Cooke, James W. Johnson, Pasquier Noterdaeme, Max Pettini, Louise Welsh, Aldric Wong, Céline Péroux   +6 more
doaj   +1 more source

Aperture Synthesis of Interstellar Neutral Hydrogen in Absorption [PDF]

, 1973
NOTE: Text or symbols not renderable in plain ASCII are indicated by [...]. Abstract is included in .pdf document. The Owens Valley Radio Observatory interferometer has been used to carry out a program of aperture synthesis in the interstellar neutral
Greisen, Eric Winslow
core   +1 more source

Characterizing the Signals and Backgrounds in a Low Earth Orbiting Cherenkov Detector, and Background Mitigation Strategies

Journal of Geophysical Research: Space Physics, Volume 131, Issue 3, March 2026.
Abstract Cherenkov detectors have been used in space for decades to measure Galactic Cosmic Rays (GCRs), Solar Energetic Particles (SEPs) and trapped particles. We present proof‐of‐concept GRAS/Geant4 simulations to both show that a cubic fused silica Cherenkov detector with SiPM in LEO has a good sensitivity to SEP and GCR protons as a function of cut‐
C. S. W. Davis, F. Lei, K. Ryden, C. Dyer, G. Santin, P. Jiggens, M. Heil   +6 more
wiley   +1 more source

Regarding the Detection of Interstellar C4 and C5 Molecules

The Astrophysical Journal
Analysis of very high signal-to-noise ratio (S/N) spectra of reddened stars allowed us to determine an upper limit (UL) of the column density N (C _4 ).
G. A. Galazutdinov, E. I. Kazanina, J. Krełowski   +2 more
doaj   +1 more source

The Constraint of Crewed Mars Missions Based on Current Radiation Dose Measurements

Space Weather, Volume 24, Issue 3, March 2026.
Abstract Crewed missions to Mars will be a milestone of future space exploration programs. However, the absence of Earth's magnetic field leaves astronauts directly exposed to unattenuated energetic particles in deep space, primarily galactic cosmic rays (GCRs), resulting in significantly higher radiation levels and enhanced health risks. Understanding
Chao Zhang, Weihao Liu, Jingnan Guo, Mikhail Dobynde, Robert F. Wimmer‐Schweingruber   +4 more
wiley   +1 more source

Chemical Composition of Interstellar Material

, 1985
Abundances in Interstellar clouds, as determined from interstellar absorption lines, are discussed first, including abundances in ‘abnormal’ (high-velocity) clouds.
Pottasch, S. R., S. R. Pottasch
core   +3 more sources

The Local Group L-band Survey: Probing Cold Atomic Gas in IC 10 with Neutral Hydrogen Absorption

The Astrophysical Journal
We present the first localized detections of the cold neutral medium (CNM) in IC 10, offering a rare view of dense atomic gas in a low-metallicity ( Z / Z _⊙  ∼ 0.27) dwarf galaxy.
Ioana A. Stelea, Snežana Stanimirović, Nickolas M. Pingel, Hongxing Chen, Eric W. Koch, Adam K. Leroy, Erik Rosolowsky, Chang-Goo Kim, Alberto D. Bolatto, Julianne J. Dalcanton, Michael P. Busch, Harrisen Corbould, J. R. Dawson, Cosima Eibensteiner, Amanda Kepley, Melanie Krips, Claire E. Murray, Julia Roman-Duval, Daniel R. Rybarczyk, Evan D. Skillman, Elizabeth Tarantino, Vicente Villanueva, Thomas G. Williams   +22 more
doaj   +1 more source

Electronic Spectroscopy of Cold Gas‐Phase Ions in a Cryogenic Ion Trap: Vibronic States, Bonding Characteristics, and Photochemistry

Chemistry – An Asian Journal, Volume 21, Issue 4, 25 February 2026.
Recent development of cryogenic ion‐trap‐based instrumentation has extended the scope of gas‐phase laser spectroscopy to a wide variety of nonvolatile ions, including carbocations and protonated hydrocarbons, organic dyes, host‐guest complexes, micro‐hydrated ions, hypervalent ions, metal clusters, and ionic intermediates formed in solution.
Satoru Muramatsu, Masahiro Koyama, Yoshiya Inokuchi   +2 more
wiley   +1 more source

Aliphatic hydrocarbon content of interstellar dust

, 2020
The mid-IR spectrum of the interstellar medium contains both aromatic and aliphatic hydrocarbon features. These are generally attributed to carbonaceous dust.
Günay B., Burton M.G., Schmidt T.W., Rawal A.   +3 more
core   +1 more source