March 1982:space activities report

NEW UK SATELLITE

The UK has agreed to contribute a free-flying sub-satellite
(UKS) to the Active Magnetospheric Particle Tracer Explorers
(AMPTE) project which is due for a Shuttle launch in 1984. The two other satellites are being built by the Americans and
Germans (described in last month’s Space Report).

During lauhch, UKS will form the structural link between
the German and US spacecraft, but thereafter will keep station
within 100 km of the German spacecraft - the Ion Release
Module (IRM) - in order to study a series of barium and
lithium ion releases to be made from IRM. There will be a
total of seven such releases into the solar wind and radiation
and plasma environment of the Earth over the nine months of
the mission.

The American satellite - the Charge Composition
Explorer (CCE) - will orbit through the radiation zones closer
to the Earth in order to detect the arrival of the "tracer" ions.
The three satellites will also join forces to make extensive
measurements with unprecendented resolution of the Earth’s
natural plasma envirnoment.

One release of barium ions, planned near Christmas 1984,
will create what will appear from the ground for some 30
minutes as an artificial comet, interacting with the solar wind
in much the same way as a real comet. The releases will be
visible mainly from North and South America where a suitable
chain of ground observing stations and spotter planes can be
made available.

The release of the tracer gases from the IRM will trace the
flow of matter and energy from the solar wind into and through
the Earth’s magnetosphere, while simultaneously examining
the complex sequence of plasma processes triggered by such
releases. The experimenters expect to observe a rich spectrum
of plasma waves, electron and ion acceleration and the for¬
mation of a magnetic cavity among many other phenomena.

Although weighing only 69 kg, UKS is nevertheless highly
complex. The satellite will be controlled via the 12 m dish
antenna at the Rutherford Appleton Laboratory to remain
within some 100 km of the IRM using an on-board radar and
propulsion system. The instruments will measure magnetic
fields, detect positive ions in the energy range 5 eV-20 keV,
detect electrons in the energy range 40 eV-25 keV, investigate
wave/particle interactions including positive-ion and electron
modulations, and detect plasma waves by making measurements of the electric and magnetic components at frequencies
from-0.1-64 Hz.

FAGET RETIRES

Maxime A. Faget, father of the Mercury spacecraft, retired
from NASA shortly after the STS-2 mission to be a consultant
and to carry out private investigations of several energy conservation schemes.

Faget, Director of Engineering and Development at the
Johnson Space Center since 1961, said that he planned to
remain closely associated with the space programme as a
consultant.

Faget joined the Langley Research Center in 1946 as a
research scientist into pilotless aircraft. He was later named
head of performance aerodynamics, a post he held until 1958.

His creative drive and engineering perception resulted in
his selection as one of the original group of 35 assigned as a
nucleus of the Johnson Space Center (then the Space Task
Group), serving three years as Chief of the Flight Systems
Division.

PROPULSION MODULE

The Inertial Upper Stage (IUS) will be used in conjunction
with the Shuttle to take payloads into geostationary orbits
(GEO) - but other stages may appear.

A TRW study -
described by Dr. Brodsky in his paper “An Economical And
Flexible Alternative Orbital Transfer Vehicle” presented at
the 32nd IAF Congress - proposes an all-liquid low-thrust
propulsion module.

The study took the case of a growth version of the TDRS
communications satellite which the present all-solid IUS would
be unable to handle.

Propellants for the module - nitrogen tetroxide and monomethyl hydrazine - would be stored in six tanks arranged
within a framework, using a pressure system to feed two 300 lbf
engines of the type used on the Viking Mars missions. This
initial version could take about 5200 lb into GEO but masses
of up to 10,0001b could be handled by increasing the tanks’ lengths.