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Related papers: Microwave Observations of Venus with CLASS

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Planetary-scale waves are thought to play a role in powering the yet-unexplained atmospheric superrotation of Venus. Puzzlingly, while Kelvin, Rossby and stationary waves manifest at the upper clouds (65--70 km), no planetary-scale waves or…

We derive Galactic continuum spectra from 5-96/cm from COBE/FIRAS observations. The spectra are dominated by warm dust emission, which may be fit with a single temperature in the range 16-21 K (for nu^2 emissivity) along each line of sight.…

The absence of plate tectonics and the young surface age (0.3-1 billion years) of Venus have led to diverse geodynamic models for Venus. The energetics of the Venusian interior drive these models; however, the lack of direct constraints on…

Earth and Planetary Astrophysics · Physics 2025-07-14 Javier Ruiz , Alberto Jiménez-Díaz , Isabel Egea-González , Ignacio Romeo , Jon F. Kirby , Pascal Audet

We present and discuss the results of VLBI (EVN) observations of three low-luminosity (P(5 GHz)<10^25 W/Hz) Broad Emission Line AGNs carefully selected from a sample of flat spectrum radio sources (CLASS). Based on the total and the…

Astrophysics · Physics 2009-11-07 A. Caccianiga , M. J. M. Marcha , A. Thean , J. Dennett-Thorpe

Recently published ALMA observations suggest the presence of 20 ppb PH$_3$ in the upper clouds of Venus. This is an unexpected result, as PH$_3$ does not have a readily apparent source and should be rapidly photochemically destroyed…

Earth and Planetary Astrophysics · Physics 2021-03-17 Alex B. Akins , Andrew P. Lincowski , Victoria S. Meadows , Paul G. Steffes

Based on measurements with the Effelsberg 100-m telescope, a multi-line study of molecular species is presented toward the gravitational lens system PKS1830-211. Obtaining average radial velocities and performing Large Velocity Gradient…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 C. Henkel , K. M. Menten , M. T. Murphy , N. Jethava , V. V. Flambaum , J. A. Braatz , S. Muller , J. Ott , R. Q. Mao

Juno Microwave Radiometer (MWR) observations of Jupiter's mid-latitudes reveal a strong correlation between brightness temperature contrasts and zonal winds, confirming that the banded structure extends throughout the troposphere. However,…

Earth and Planetary Astrophysics · Physics 2021-10-28 L. N. Fletcher , F. A. Oyafuso , M. Allison , A. Ingersoll , L. Li , Y. Kaspi , E. Galanti , M. H. Wong , G. S. Orton , K. Duer , Z. Zhang , C. Li , T. Guillot , S. M. Levin , S. Bolton

Far-ultraviolet spectra of Venus and Mars in the range 820-1840 A at 4 A resolution were obtained on 13 and 12 March 1995, respectively, by the Hopkins Ultraviolet Telescope (HUT), which was part of the Astro-2 observatory on the Space…

Astrophysics · Physics 2009-10-31 Paul D. Feldman , Eric B. Burgh , Samuel T. Durrance , Arthur F. Davidsen

Planetary-scale waves at the Venusian cloud-top cause periodic variations in both winds and ultraviolet (UV) brightness. While the wave candidates are the 4-day Kelvin wave and 5-day Rossby wave with zonal wavenumber 1, their temporal…

We present spatially resolved observations of Betelgeuse (Alpha Orionis) obtained with the Karl G. Jansky Very Large Array (VLA) at wavelengths of ~7mm (44~GHz) and ~1.3cm (22~GHz) on 2019 August 2, just prior to the onset of the historical…

Solar and Stellar Astrophysics · Physics 2022-08-17 L. D. Matthews , A. K. Dupree

We have used the Sydney University Stellar Interferometer (SUSI) to measure the angular diameter of the F9 V star beta Virginis. After correcting for limb darkening and combining with the revised Hipparcos parallax, we derive a radius of…

We present the observational results from the 43-GHz Very Long Baseline Array (VLBA) observations of 124 compact radio-loud active galactic nuclei (AGNs) that were conducted between 2014 November and 2016 May. The typical dimensions of the…

High Energy Astrophysical Phenomena · Physics 2020-07-07 X. -P. Cheng , T. An , S. Frey , X. -Y. Hong , X. He , K. I. Kellermann , M. L. Lister , B. -Q. Lao , X. -F. Li , P. Mohan , J. Yang , X. -C. Wu , Z. -L. Zhang , Y. -K. Zhang , W. Zhao

The detection of phosphine (PH3) in the atmosphere of Venus has been recently reported based on millimeter-wave radio observations (Greaves et al. 2020), and its re-analyses (Greaves et al. 2021a/b). In this Matters Arising we perform an…

A fundamental result of quantum mechanics is that the fluctuations of a bosonic field are given by its temperature $T$. An electromagnetic mode with frequency $\omega$ in the microwave band has a significant thermal photon occupation at…

The ARCADE 2 instrument has measured the absolute temperature of the sky at frequencies 3, 8, 10, 30, and 90 GHz, using an open-aperture cryogenic instrument observing at balloon altitudes with no emissive windows between the beam-forming…

Cosmology and Nongalactic Astrophysics · Physics 2016-10-05 D. J. Fixsen , A. Kogut , S. Levin , M. Limon , P. Lubin , P. Mirel , M. Seiffert , J. Singal , E. Wollack , T. Villela , C. A. Wuensche

We report on a measurement of the temperature of the cosmic microwave background radiation field, T_CMB, at z = 0.88582 by imaging HC3N (3-2) and (5-4) absorption in the foreground galaxy of the gravitationally lens magnified radio source…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Mayumi Sato , Mark J. Reid , Karl M. Menten , Chris L. Carilli

A balloon-borne experiment has measured the absolute temperature of the cosmic microwave background radiation (CMBR) at 10.7 GHz to be Tcmbr = 2.730 +- .014 K. The error is the quadratic sum of several systematic errors, with statistical…

Astrophysics · Physics 2016-08-30 S. T. Staggs , N. C. Jarosik , S. S. Meyer , D. T. Wilkinson

We report a model study on the effects of clouds on emission spectra of super-Venus planets. Our goal is to assess possible ways to identify characteristic spectral features due to clouds. We show that it is possible to distinguish an…

Earth and Planetary Astrophysics · Physics 2022-02-09 Paulina Wolkenberg , Diego Turrini

We investigate the nature of the compact, and possibly variable nuclear radio source in the centre of WISE J0716-19, the proposed host galaxy of fast radio burst, FRB 150418. We observed WISE J0716-19 at 5.0 GHz with the European VLBI…

Astrophysics of Galaxies · Physics 2016-09-28 M. Giroletti , B. Marcote , M. Garrett , Z. Paragi , J. Yang , K. Hada , T. W. B. Muxlow , C. C. Cheung
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