RPA aeronomy experiment onboard the Indian satellite SROSS-C2 - Some important aspects of the payload and satellite

Abstract

An aerono my pay load of re tarding po te ntial analyser (RPA ) consisting of an e lectron RPA. ion RPA and a potc ntial probe (PP), designed and developed a t the Natio nal Physical Laboratory, New Delh i. was fl own onboard the Indi an sate lli te SROSS-C2 o n 4 May 1994, fo r making ill silll measurements of F-regio n ionospheri c plasma. The objecti ve of the mi ss ion was to investi ga te the char;)cteris ti cs and energe tics of the equato ri a l and low latitude ionosphere I thermosphere over the Indi an rcgion. The SROSS-C2 was a spin -stabili zed o rbit ing sate llite placed in an e lli pt ica l orbit hav ing orbit inclinatio n of 46.3°. The payload made s imu ltaneous sampling o f e lectron and io n plasma in the aititude range of 420-020 km for more than half a solar cycle from minima to max ima o f the 23'd sola r cycle act ivity. During initi a l phase o f the miss ion . measurements were made in a higher orbit fo r a li mited peri od o f two months. whi le the sa te llite apogee was at (riO kill kceping the pe rigee same. T he total ion density. e lec tron and ion te mperatures. ion com positi on. supra-the rmal e lec tron Ilu and irregulariti es in e lec tron and ion de nsities a long the sate llite o rbit can be derived from the measure me nts. In thi s paper. some important aspec ts o f the sc ient ific pay loads, the sate llite and its o rbital confi gurati on. w hi ch ;.I re importa nt ill understanding the pay load opera tion in space for data collectio n inc luding the analys is o f data and the ir inte rprctations. a rc descri bed.