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Authors: Szalay J. R., Pokorný P., Bale S. D., Christian E. R., Goetz K., et al.
Title: The Near-Sun Dust Environment: Initial Observations from Parker Solar Probe

The Parker Solar Probe (PSP) spacecraft has flown into the densest, previously unexplored, innermost region of our solar system’s zodiacal cloud. While PSP does not have a dedicated dust detector, multiple instruments on the spacecraft are sensitive to the effects of meteoroid bombardment. Here, we discuss measurements taken during PSP’s second orbit and compare them to models of the zodiacal cloud’s dust distribution. Comparing the radial impact rate trends and the timing and location of a dust impact to an energetic particle detector, we find the impactor population to be consistent with dust grains on hyperbolic orbits escaping the solar system. Assuming PSP’s impact environment is dominated by hyperbolic impactors, the total quantity of dust ejected from our solar system is . . .
Date: 02/2020 Publisher: The Astrophysical Journal Supplement Series Pages: 27 DOI: 10.3847/1538-4365/ab50c1 Available at:
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Authors: Němeček Zdeněk, Ďurovcová Tereza, Šafránková Jana, Richardson John D., Šimůnek Jiří, et al.
Title: (Non)radial Solar Wind Propagation through the Heliosphere

The solar wind nonradial velocity components observed beyond the Alfvén point are usually attributed to waves, the interaction of different streams, or other transient phenomena. However, Earth-orbiting spacecraft as well as monitors at L1 indicate systematic deviations of the wind velocity from the radial direction. Since these deviations are of the order of several degrees, the calibration of the instruments is often questioned. This paper investigates for the first time the evolution of nonradial components of the solar wind flow along the path from ≍0.17 to 10 au. A comparison of observations at 1 au with those closer to or farther from the Sun based on measurements of many spacecraft at different locations in the heliosphere (Parker Solar Probe, Helios 1 and 2, Wind, Advanced Co. . .
Date: 07/2020 Publisher: The Astrophysical Journal Pages: L39 DOI: 10.3847/2041-8213/ab9ff7 Available at:
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Authors: Howard R. A., Vourlidas A., Bothmer V., Colaninno R. C., DeForest C. E., et al.
Title: Near-Sun observations of an F-corona decrease and K-corona fine structure

Remote observations of the solar photospheric light scattered by electrons (the K-corona) and dust (the F-corona or zodiacal light) have been made from the ground during eclipses and from space at distances as small as 0.3 astronomical units to the Sun. Previous observations of dust scattering have not confirmed the existence of the theoretically predicted dust-free zone near the Sun. The transient nature of the corona has been well characterized for large events, but questions still remain (for example, about the initiation of the corona and the production of solar energetic particles) and for small events even its structure is uncertain. Here we report imaging of the solar corona during the first two perihelion passes (0.16-0.25 astronomical units) of the Parker Solar Probe spacecraft. . .
Date: 12/2019 Publisher: Nature Pages: 232 - 236 DOI: 10.1038/s41586-019-1807-x Available at:
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Authors: Banks Michael
Title: NASA launches Parker Solar Probe mission to ’touch’ the Sun

NASA has launched a mission to study the Sun’s atmosphere and solar wind that will come far closer to our star than any other craft before.

Date: 09/2018 Publisher: Physics World Pages: 7 - 7 DOI: 10.1088/2058-7058/31/9/11 Available at:
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Authors: Stansby David, Salem Chadi, Matteini Lorenzo, and Horbury Timothy
Title: A New Inner Heliosphere Proton Parameter Dataset from the Helios Mission

In the near future, Parker Solar Probe and Solar Orbiter will provide the first comprehensive in-situ measurements of the solar wind in the inner heliosphere since the Helios mission in the 1970s. We describe a reprocessing of the original Helios ion distribution functions to provide reliable and reproducible data to characterise the proton core population of the solar wind in the inner heliosphere. A systematic fitting of bi-Maxwellian distribution functions was performed to the raw Helios ion distribution function data to extract the proton core number density, velocity, and temperatures parallel and perpendicular to the magnetic field. We present radial trends of these derived proton parameters, forming a benchmark to which new measurements in the inner heliosphere will be compared. . . .
Date: 11/2018 Publisher: Solar Physics DOI: 10.1007/s11207-018-1377-3 Available at:
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Title: News at a glance

In science news around the world, the U.S. National Institutes of Health (NIH) responds to a report on "foreign influences," Australia slashes its future research funding, Mars’s methane mystery deepens, and the Paris agreement on climate change survives a contentious rulemaking session in Poland. Also, astronomers discover the solar system’s farthest-known planet, NIH comes under fire for clinical trial reporting results, the late Paul Allen bequests a new immunology research institute, and NASA’s Parker Solar Probe makes its first dip into the sun’s atmosphere. Plus, a new study suggests tourists and scientists are making Antarctica’s birds sick, and an interview with a Harvard University historian helps explain India’s monsoon—one of Asia’s most important weather patt. . .
Date: 12/2018 Publisher: Science Pages: 1334 - 1336 DOI: 10.1126/science.362.6421.1334 Available at:
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Authors: Lawrence David J., Feldman William C., Gold Robert E., Goldsten John O., and McNutt Ralph L.
Title: The neutron, gamma-ray, X-ray spectrometer (NGXS): A compact instrument for making combined measurements of neutrons, gamma-rays, and X-rays

The Neutron, Gamma ray, and X-ray Spectrometer (NGXS) is a compact instrument designed to detect neutrons, gamma-rays, and hard X-rays. The original goal of NGXS was to detect and characterize neutrons, gamma-rays, and X-rays from the Sun as part of the Solar Probe Plus mission in order to provide direct insight into particle acceleration, magnetic reconnection, and cross-field transport processes that take place near the Sun. Based on high-energy neutron detections from prompt solar flares, it is estimated that the NGXS would detect neutrons from 15 to 24 impulsive flares. The NGXS sensitivity to 2.2 MeV gamma rays would enable a detection of ̃50-60 impulsive flares. The NGXS is estimated to measure ̃120 counts/s for a GOES C1-type flare at 0.1 AU, which allows for a large dynamic ra. . .
Date: 01/2014 Publisher: Acta Astronautica Pages: 524 - 529 DOI: 10.1016/j.actaastro.2012.06.017 Available at:
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