24 January, 20011st NOZOMI_MEX Science Workshop, Jan, 2001 R. Lundin, M. Yamauchi, and H. Borg, Swedish Institute of Space Physics H. Hayakawa, M. Hirahara, T. Mukai, Institute of Space and Astronautics Science IMI - Nozomi Ion Mass Imager Nozomi orbit

24 January, 20011st NOZOMI_MEX Science Workshop, Jan, 2001 Ion Mass Imager, IMI, on Nozomi Measures E/q of ions ( KeV/e) H +, He ++, He +, O +, and O 2 +,CO 2 + (mol ions) 3D observation every half spin

24 January, 20011st NOZOMI_MEX Science Workshop, Jan, 2001 View from S/C antenna (towards the Earth) IMI Cross Section (& meas. Principles)

24 January, 20011st NOZOMI_MEX Science Workshop, Jan, 2001 IMI characteristics

24 January, 20011st NOZOMI_MEX Science Workshop, Jan, 2001 He ++ H+H+ IMI data of the Solar Wind (1999 & 2000)

24 January, 20011st NOZOMI_MEX Science Workshop, Jan, 2001 Nozomi Cruise Phase Science 3-D plasma structure of the solar wind. The unsusual Nozomi orbit, 0.1 AU above the Earth (spring 2003), is an opportunity for STP studies (e.g. SOHO, Cluster etc) Cruise solar wind studies with Mars-Express => Analysis of the heliospheric current sheet, and other interplanetary phenomena (e.g., interplanetary field-aligned current, k-vector measurement) Martian Science Escape of ions and neutrals, faciliated by a relatively low gravity and weak magnetic field and an atmosphere and ionosphere directly exposed to the solar wind. The escape velocity 5 km/s => escape energies 2.1 eV for O + and 4.2 eV for O 2 +. Dawn-dusk asymmetries of the Martian bow-shock Expanded neutral atmosphere /corona (low gravity and weak magnetic field). Neutral gas expand beyond the bow shock, enhancing the interaction with the solar wind (mass loading etc.). Venus-like (and comet-like) interaction with the solar wind due to the weak intrinsic magnetic field.

24 January, 20011st NOZOMI_MEX Science Workshop, Jan, 2001

24 January, 20011st NOZOMI_MEX Science Workshop, Jan, 2001 Outgassing from the surfaces of the two Martian satellites, Phobos and Deimos. Asymmetry of the neutral corona - decisive factors may be a thin atmosphere, a relatively slow rotation, and magnetospheric forcing. The asymmetry does not disappear in the tail because of the relatively large gyroradii compared to the size of the Martian magnetosphere. Interesting boundary layer physics in an environment of weak magnetic fields, large ion gyroradii, and an expanded corona. Martian Science (cont) Studies of the bow shock (asymmetric comet-like transition, backstreaming and acceleration), mass-loading boundary (planetopause?), magnetopause (or proton dropout boundary), and ionopause.

24 January, 20011st NOZOMI_MEX Science Workshop, Jan, 2001 Critical Martian science issues : (1) The Martian bow shock How far does back-streaming of ions and electrons travel from the quasi-parallel shock? Rate of ion pickup phenomena in the flanks? CIV phenomenon? (2) Boundary layers Consensus lacking on classi- fication, locations, and physical role of various boundaries Dynamics, dawn-dusk asymmetry, and solar wind dependence?

24 January, 20011st NOZOMI_MEX Science Workshop, Jan, 2001 Critical Martian science issues (cont): (3) Phobos ring and Deimos torus Plasma tail from the dust ring Dusty plasma and a dense plasma in the dust ring? Outgassing? (4) Ion energization process To the SW velocity, to the SW energy, or to twice the SW energy? SW condition during energization event. O + energization Acceleration in the central plasma sheet Acceleration mechanism (Electrostatic, waves, or MHD)

24 January, 20011st NOZOMI_MEX Science Workshop, Jan, ) Helium and molecular ions Helium rich sources? Non-thermal escape from the atmosphere Molecular ions in the plasma sheet Additional sources of ions other than the atmosphere (Phobos and Deimos?) 6) The effect of localized magnetic induction regions on the solar wind interaction with Mars Perturbed magnetosphere shape ? Localized ”cusp” regions? Enhanced atmospheric escape? Impact on weather? Critical Martian science issues (cont):