Περίληψη:
Formation Flying opens the possibility to conceive and deploy giant
solar coronagraphs in space permanently reproducing the optimum
conditions of a total eclipse of the Sun (”artificial” eclipse)
thus giving access to the inner corona with unprecedented spatial
resolution and contrast (low stray light). The first opportunity to
implement such a coronagraph “ASPIICS” will be offered by the
European Space Agency (ESA) PROBA-3 technology mission devoted to the
in-orbit demonstration of formation flying technologies. Two spacecrafts
separated by about 150 m form a giant externally-occulted coronagraph:
the optical part hosted by one spacecraft remains entirely protected
from direct sunlight by remaining in the shadow of an external occulter
hosted by the other spacecraft. We developed and tested a scale-model
‘breadboard’ (i.e., 30m) of the PROBA-3/ASPIICS Formation Flying
coronagraph. The investigations focused on two metrology systems capable
of measuring both the absolute pointing of the coronagraph (by sensing
the projected shadow and penumbra produced by the external occulting
disk) and the alignment of the formation (by re-imaging light sources
located on the rear-side of the occulting disk with the optical part of
the coronagraph). In this contribution, we will describe the
demonstrator and report on our results on the crucial question of the
alignment and pointing in space of long instruments (> 100 m) with an
accuracy of a few arcsec. This study has been conducted in the framework
of an ESA “STARTIGER” Initiative, a novel approach aimed at
demonstrating the feasibility of a new and promising technology on a
very short time scale (six months).
Συγγραφείς:
Vives, Sebastien
Dame, Luc
Lamy, Philippe
Antonopoulos, A.
and Bon, W.
Capobianco, G.
Crescenzio, G.
Da Deppo, V. and
Ellouzi, M.
Garcia, J.
Guillon, C.
Mazzoli, A.
Soilly,
T.
Stathopoulos, F.
Tsiganos, C.
