The penetrator to be released will be spun about its longitudinal axis for stability and ejected. Entry occurs 21-22 hours later. It is possible to deploy both penetrators on a single orbit. In the martian atmosphere, the probes undergo aerodynamic braking, first using a rigid cone and then an air-inflated braking device, until a given velocity is reached to provide their penetration into martian regolith. The penetrating part of the probe forebody, carrying the scientific and housekeeping instrumentation, enters the regolith down to 5-6 m, while the aftbody, with the rest of the instrumentation, remains on the surface.
Scientific studies begin after penetration.
Data are relayed to Earth by the Orbiter. Figure from IKI Mars '96 Mission Page 7. The orbital period will be adjusted to permit relay of the lander data. The orbital period permits 5-6 minute relays every seven days. After 50-60 days, the orbit periapsis will precess into the illuminated portion of Mars, and the Orbiter's surface and atmosphere instruments will be used extensively.