scholarly journals Observation of a New Type of Flare

1957 ◽  
Vol 10 (2) ◽  
pp. 319 ◽  
Author(s):  
RJ Bray ◽  
RE Loughhead ◽  
VR Burges ◽  
Marie K McCabe
Keyword(s):  
Maximum Intensity ◽  
Line Of Sight ◽  
The Sun ◽  
Observational Material ◽  
New Type ◽  
Points Of View

The importance of chromospheric flares from both the astrophysical and geophysical points of view is now generally recognized, but, in spite of the extensive observational material collected by Ellison, Dodson, and others, it must be admitted that the mechanism of their origin is still little understood. In this paper we present observations of a hitherto unobserved phenomenon, namely, the ejection of a mass of very bright material from a flare some 28� from the limb of the Sun. The ejection occurred several minutes before flare maximum. It was approximately 10,000 by 30,000 km in size and moved outwards with a velocity across the line-of-sight of 300 km/sec. As it did so, it brightened appreciably, reaching maximum intensity 3� min after expulsion, its height then being 25,000 km. The ejection was quite unlike the dark surge prominences often emitted from flares, and in fact, except for its motion, possessed all the properties of a small flare.

Performance of 4G-LTE Communication and Navigation System in Blended Wing-Body UAS

2019 ◽  
Vol 8 (4) ◽  
pp. 9538-9542
Keyword(s):  
Satellite Communication ◽  
Line Of Sight ◽  
Multiple Factors ◽  
The World ◽  
New Type ◽  
Blended Wing Body ◽  
4G Lte ◽  
The Right ◽  
And Control ◽  
Technology Demonstrator

In vision of searching for the right Unmanned Aerial System (UAS) for a specific mission, there are multiple factors to be considered by the operator such as mission, endurance, type of payload and range of the telemetry and control. This research is focusing on extending control range of the UAS by using 4G-LTE network to enable beyond-line-of-sight flying for the commercial UAS. Major UAS such Global Hawk, Predator MQ-1 are able to fly thousands of kilometers by the use of satellite communication. However, the satellite communication annual license subscription can be very expensive. With this situation in mind, a new type of flight controller with 4G-LTE communication has been developed and tested. Throughout the research, blended-wing-body (BWB) Baseline B2S is used as the platform for technology demonstrator. Result from this analysis has proven that the proposed system is capable to control a UAS from as far as United Kingdom, with a latency less than 881 ms in average. The new added capability can potentially give the commercial UAS community a new horizon to be able to control their UAS from anywhere around the world with the availability of 4G-LTE connection

scholarly journals Unbound Close Stellar Encounters in the Solar Neighborhood

2022 ◽  
Vol 163 (2) ◽  
pp. 44
Author(s):  
Bradley M. S. Hansen
Keyword(s):  
Spectral Type ◽  
Main Sequence ◽  
Radial Distance ◽  
Solar Neighborhood ◽  
Limiting Factors ◽  
Line Of Sight ◽  
The Sun ◽  
Finite Set ◽  
Host Stars ◽  
Migration Event

Abstract We present a catalog of unbound stellar pairs, within 100 pc of the Sun, that are undergoing close, hyperbolic, encounters. The data are drawn from the GAIA EDR3 catalog, and the limiting factors are errors in the radial distance and unknown velocities along the line of sight. Such stellar pairs have been suggested to be possible events associated with the migration of technological civilizations between stars. As such, this sample may represent a finite set of targets for a SETI search based on this hypothesis. Our catalog contains a total of 132 close passage events, featuring stars from across the entire main sequence, with 16 pairs featuring at least one main-sequence star of spectral type between K1 and F3. Many of these stars are also in binaries, so that we isolate eight single stars as the most likely candidates to search for an ongoing migration event—HD 87978, HD 92577, HD 50669, HD 44006, HD 80790, LSPM J2126+5338, LSPM J0646+1829 and HD 192486. Among host stars of known planets, the stars GJ 433 and HR 858 are the best candidates.

scholarly journals THE TURN OF THE SCREW: HENRY JAMES AS AN AUTHOR AND A CRITIC

2020 ◽  
pp. 55-67
Author(s):  
M.B. Rarenko ◽  
Keyword(s):  
Henry James ◽  
William James ◽  
Absolute Truth ◽  
The Core ◽  
Works Of Art ◽  
Starting Point ◽  
The World ◽  
New Type ◽  
Points Of View ◽  
The Absolute

The article considers the story by Henry James (1843 – 1916) «The Turn of the Screw» (1898 – first edition, 1908 – second edition) in connection with the emergence of a new type of narrator in the writer's late prose. The worldview and creative method of H. James are formed under the influence of the philosophy of pragmatism, which became widespread at the turn of the XIX-XX centuries thanks to the works of the writer's elder brother, the philosopher William James (1842 – 1910). The core of pragmatism is the pluralistic concept of William James based on the assumption that knowledge can be realized from very limited, incomplete, and inadequate «points of view» and this leads to the statement that the absolute truth is essentially unknowable. The epistemological statements of William James's theory is that the content of knowledge is entirely determined by the installation of consciousness, and the content of the truth in this case depends on the goals and experience of the human, i.e. the central starting point is the consciousness of the person. Henry James not only creates works of art, but also sets out in detail the principles of his work both on the pages of fiction works of small and large prose, putting them in the mouths of their characters – representatives of the world of art, and in the prefaces to his works of fiction, as well as in critical works.

Variations in the Mean Line of Sight Velocity of the Sun: 1976 – 1985

1988 ◽  
pp. 215-218 ◽  
Author(s):  
A. Jiménez ◽  
P. L. Pallé ◽  
C. Régulo ◽  
T. Roca Cortés ◽  
Y. P. Elsworth ◽  
...  
Keyword(s):  
Line Of Sight ◽  
The Sun ◽  
The Mean

The Total Experience

Eclipses ◽  
2019 ◽  
Author(s):  
Frank Close
Keyword(s):  
Outer Space ◽  
Line Of Sight ◽  
The Sun

Why do colors change? In outer space, the sky is black and the Sun is a white disc, visible only in the direct line of sight—there is nothing to scatter its light. Here on Earth, in normal daylight the molecules and dust in the atmosphere...

Research on Mode of Solar Automatic Tracker

2013 ◽  
Vol 724-725 ◽  
pp. 78-83
Author(s):  
Zhong Ying Yuan
Keyword(s):  
Sustainable Development ◽  
Solar Energy ◽  
Trajectory Tracking ◽  
Utilization Rate ◽  
The Sun ◽  
Automatic Tracking ◽  
Tracking Mode ◽  
The World ◽  
New Type ◽  
Solar Tracker

Solar energy, as a new type of energy for sustainable development without pollution, has caught much attention all over the world. Adequately improving the utilization rate of solar illumination is taken as the only means of using solar energy in maximum. This paper introduces two different tracking modes of the solar tracker which can switch automatically: Sensor tracking mode and the sun trajectory tracking mode. These two modes can self-switch and cooperate with each other to achieve high precision of all time automatic tracking.

Model Calculations of the F-Corona and inner Zodiacal Light

2020 ◽  
Author(s):  
Saliha Eren ◽  
Ingrid Mann
Keyword(s):  
Size Distribution ◽  
White Light ◽  
Scattered Light ◽  
Mie Scattering ◽  
Dust Particles ◽  
Line Of Sight ◽  
The Sun ◽  
Zodiacal Light ◽  
Model Calculations ◽  
Zodiacal Dust

<p>The white-light Fraunhofer corona (F-corona) and inner Zodiacal light are generated by interplanetary (Zodiacal) dust particles that are located between Sun and observer. At visible wavelength the brightness comes from sunlight scattered at the dust particles. F-corona and inner Zodiacal light were recently observed from STEREO (Stenborg et al. 2018) and Parker Solar Probe (Howard et al. 2019) spacecraft which motivates our model calculations. We investigate the brightness by integration of scattered light along the line of sight of observations. We include a three-dimensional distribution of the Zodiacal dust that describes well the brightness of the Zodiacal light at larger elongations, a dust size distribution derived from observations at 1AU and assume Mie scattering at silicate particles to describe the scattered light over a large size distribution from 1 nm to 100 µm. From our simulations, we calculate the flattening index of the F-corona, which is the ratio of the minor axis to the major axis found for isophotes at different distances from the Sun, respectively elongations of the line of sight. Our results agree well with results from STEREO/SECCHI observational data where the flattening index varies from 0.45° and 0.65° at elongations between 5° and 24°. To compare with Parker Solar Probe observations, we investigate how the brightness changes when the observer moves closer to the Sun. This brightness change is influenced by the dust number density along the line of sight and by the changing scattering geometry.</p><p>-Stenborg G., Howard R. A., and Stauffer J. R., 2018: Characterization of the White-light Brightness of the F-corona between 5° and 24° Elongation, Astrophys. J. 862: 168 (21pp).</p><p>-Howard, R.A. and 25 co-authors, 2019: Near-Sun observations of an F-corona decrease and K-corona fine structure, Nature 576, 232–236.</p>

scholarly journals VI. The ultra-violet band of ammonia, and its occurrence in the solar spectrum

1919 ◽  
Vol 218 (561-569) ◽  
pp. 351-372 ◽  
Keyword(s):  
Solar Spectrum ◽  
Ultra Violet ◽  
Maximum Intensity ◽  
Resolving Power ◽  
The Sun ◽  
Sufficient Detail ◽  
Other Substances ◽  
Violet Band ◽  
Band Spectra

A question of great interest in connection with the solar spectrum is that of the origin of the thousands of unidentified faint lines which were catalogued by Rowland in his “Preliminary Table of Solar Spectrum Wave-lengths.” Some of these lines may possibly be identical with faint lines in metallic spectra which have not yet been completely tabulated, but in view of the presence of bands of cyanogen, carbon and hydrocarbon, the possibility of the correspondence of most of them with band spectra of other substances should not be overlooked. As a contribution to this inquiry, the present investigation was undertaken primarily in order to determine whether Group P in the ultra-violet region of the solar spectrum might not be mainly due to the presence of ammonia in the absorbing atmosphere of the sun. Ammonia was already known to give a remarkable band in this region, having its position of maximum intensity near λ 3360, but it had not been investigated in sufficient detail to permit of an adequate comparison with the solar tables. Photographs have accordingly been taken with spectrographs of high resolving power for the purpose of this comparison, and, as will appear from the details which follow, it has been established that the ammonia band is certainly represented in the solar spectrum, and accounts for a considerable number of faint lines for which no other origins have been suggested.

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