Improved formulae for determining upper-atmosphere density from the change in a satellite's orbital period

Abstract

Improved formulae are derived for determining the air density at a specified height above the perigee of a satellite's orbit from the decrease in orbital period, when due allowance is made for atmospheric rotation and oblateness, and the variation of scale height with altitude. The density is evaluated at a height chosen so that the formulae are insensitive to errors in the value used for scale height Hp at perigee: the error (s.d.) in the formulae is about 1 per cent if Hp is not in error by more than 25 per cent. BыBoдятcя юлючщeнныe фopмУлы для oпpeдeлeния плoтнocти Boздючa нa cпeцифичecкoй Bыcoтe нaд пepигeeм opбиты cнютникa oт Умeньшeния пepиoдa Bpaщeния, кoгдa дeлaeтcя нюжнoe дoпющeниe для aтмocфepнoгo Bpaщeния и cплющeннocти, и oт Bapиaции шкaлBнoй Bыcoты c aльтитюдoй. Плoтнocть oцeниBaeтcф нa Bыcoтe, пoдoбpaннoй тaк, чтo фopмУлы нeчюBcтBитeльны к oшибкaм знaчeния, иcпoльзoBaннoгo для шкaльнoй ьыcoты Hp нa пepигee: oщибкa/s.d./ B фopмюлe oкoлo oднoгo пpoцeнтa, ecли знaчeниe Hp пpaBильнo B пpeдeлaч ± 25 пpoцeнтoB.