A redundant low power PCM telemeter for the orbiting solar observatory
Redundant low power PCM telemeter for OSO
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Redundant low power PCM telemeter for OSO
OSO-II data on solar activity and electromagnetic radiation
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OSO satellites observations, studying X ray flare phases, temperatures and spectra
The performance of the OSO-7 spacecraft during the first twelve months after launch is discussed. A summary description of the spacecraft and experiments is given. Line drawings of the satellite configuration, telemetry subsystem, electronics equipment, pneumatic equipment, and optical equipment are included.
An instrument combining mechanical collimators and proportional counter detectors was designed to record solar X-rays with energies of 2-30 keV with good temperal, spectral, and spatial resolution. The overall operation of the instrument is described to the degree needed by personnel who interact with the experimenter during SC/experiment interfacing, experiment testing, observatory integration and testing, and pre/post launch data processing. The general layout of the instrument is given along with a summary of the instrument characteristics.
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The University of Colorado spectrometer aboard OSO 8 has measured the high temperature C IV resonance lines (at 1548 and 1551 A) and the Si IV resonance lines (at 1393 and 1402 A) formed in the solar chromosphere-corona transition region. Preliminary results include studies of mean profiles, a comparison of cell and network profiles, and the behavior of the lines at the extreme solar limb.
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The OSO-1 represents a recent vintage satellite, or more recent design satellite. A summary of the battery design used on OSO-1 is presented. The temperature effects on voltage and charging-discharging of the battery system are discussed.
The ionosphere, ionosheath, ionopause, and bow shock wave of Venus are characterized. Venus is found to have a well-defined strong standing bow shock wave. In the ionosheath, downstream from the shock, compressed and heated postshock plasma apparently interacts directly with the ionosphere. Plasma ion velocity deflections suggest that the ionopause has a blunt shape. The positions of the bow shock and ionopause are variable and appear to respond to changes in the external solar wind pressure.
Oscillations, physical properties of the solar atmosphere, motions in the quiet solar atmosphere, coronal holes, motions in solar active regions, solar flares, the structure of plage regions, an atlas, and aeronomy are summarized. Photometric sensitivity, scattered light, ghosts, focus and spectral resolution, wavelength drive, photometric sensitivity, and scattered light, are also summarized. Experiments are described according to spacecraft made and experiment type. Some of the most useful data reduction programs are described.
The possibility is considered that a spherical distribution of dark matter (DM), matter not visible with current instruments, is trapped in the sun's gravitational field. Bounds are placed from the motion of Uranus and Neptune, on the amount of DM that could be so trapped within the radius of those planets' orbits, as follows: from the Voyager 2, Uranus-flyby data new, more accurate ephemeris values are generated. Trapped DM mass is bounded by noting that such a distribution would increase the effective mass of the sun as seen by the outer planets and by using the new ephemeris values to bound such an increase.
We improve, using a larger set of observations including Voyager 2 Neptune flyby data, previous bounds on the amount of dark matter (DM) trapped in a spherically symmetric distribution about the Sun. We bound DM by noting that such a distribution would increase the effective mass of the Sun as seen by the outer planets and by finding the uncertainty in that effective mass for Uranus and Neptune in fits to the JPL developmental ephemeris residuals, including optical data and those two planets' Voyager 2 flybys. We extend our previous procedure by fitting more parameters of the developmental ephamerides. In addition, we present here the values for Pioneer 10, Pioneer 11, Voyager 1, and Voyager 2 Jupiter-ranging normal points (and incorporate these data as well). Our principal result is to limit DM in spherically symmetric distributions in orbit about the Sun interior to Neptune's orbit to less than Earth mass and interior to Uranus's orbit to about 1/6 of Earth's mass.
The Spectral Imaging of Coronal Environment (SPICE; SPICE Consortium et al. 2020) provides an extraordinary opportunity to study the chromosphere and transition region using EUV wavelengths, e.g., Ne VIII 770 Å, CIII 977 Å, OVI 1032 Å, and Lyman-𝛽 025 Å. We present results modeling Ne VIII 770 Å intensity using images from SPICE and the COronal DEnsity and Temperature (CODET) model. This model is based on relationships between the magnetic field, density, and temperature. It uses a flux transport model, the Potential Field Extrapolation model (PFSS), an emission model based on Chianti atomic database 10.0.2, and an optimization algorithm. In addition, we assume that the emission from the top of the transition region (Ne VIII 770 Å) can be described using the magnetic field in the coronal base at 1.014𝑅⨀ (from PFSS). We found the mean full disc electron density in the transition region obtained from the CODET model for Ne VIII 770 Å (𝑙𝑜𝑔10𝑇[𝐾] = 5.8) corresponds to ∼ 𝑙𝑜𝑔10𝑁 𝑐𝑚−3 >9, and temperature value is 𝑙𝑜𝑔10𝑇[𝐾]~6. This value agrees with the Ne VIII 770 Å temperature formation 𝑙𝑜𝑔10𝑇[𝐾]~5.8. The density above sunspots (𝐵 > 50 𝐺) corresponds to 𝑙𝑜𝑔10𝑁 𝑐𝑚−3 > 9, while in quiet Sun regions (𝐵 < 50 𝐺) the mean density is 𝑙𝑜𝑔10𝑁[𝑐𝑚−3 ] = 8 .
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