Search Publications
Kinetic parameters of interstellar neutral helium. Review of results obtained during one solar cycle with the Ulysses/GAS-instrument
Witte, M.
The GAS-instrument onboard the space probe Ulysses is designed to measure the local angular distribution of the flow of interstellar neutral He-atoms within ≈3 AU distance from the sun. It allows to infer the kinetic parameters (velocity vector, temperature and density) of these particles outside the heliosphere (``at infinity''). During three obs…
Synopsis of the interstellar He parameters from combined neutral gas, pickup ion and UV scattering observations and related consequences
Möbius, E.; Noda, H.; Bzowski, M. +17 more
A coordinated effort to combine all three methods that are used to determine the physical parameters of interstellar gas in the heliosphere has been undertaken. In order to arrive at a consistent parameter set that agrees with the observations of neutral gas, pickup ions and UV backscattering we have combined data sets from coordinated observation…
Observations of the helium focusing cone with pickup ions
Geiss, J.; Möbius, E.; Noda, H. +12 more
The helium gravitational focusing cone has been observed using pickup He+, first during the solar minimum in 1984-1985 with the AMPTE/IRM spacecraft, and again in more detail from 1998 to 2002 with ACE and in 2000 with Nozomi. Five traversals of the cone allow us to obtain an accurate determination of the ecliptic longitude of the inter…
Filtration of interstellar H, O, N atoms through the heliospheric interface: Inferences on local interstellar abundances of the elements
Geiss, J.; Gloeckler, G.; Izmodenov, V. +1 more
In this Letter we report on our study of the filtration of interstellar atoms of hydrogen, oxygen and nitrogen in the interaction region between the solar wind and the local interstellar medium. The filtration has great importance for the determination of local interstellar abundances of these elements, which becomes now possible due to measuremen…
Heliospheric conditions that affect the interstellar gas inside the heliosphere
Möbius, E.; Bzowski, M.; Lallement, R. +9 more
The interstellar gas that flows through the heliosphere is strongly affected by ionization close to the Sun, in particular solar photoionization, electron impact, and charge exchange. Therefore, the interpretation of any observation of interstellar gas in the inner heliosphere hinges upon the accurate knowledge of these effects and their variation…
Analysis of Ulysses data: Radiation pressure effects on dust particles
Krüger, H.; Grün, E.; Wehry, A.
The objective of this paper is to illustrate the influence of the radiation pressure and the electromagnetic force on dust particles in interplanetary space. Between 1990 and 2001 62 so-called β-meteoroids (β describes the ratio of the radiation pressure force to gravity) were detected as dust particles coming from the inner solar system on hyperb…