Atmospheric drag force on LAPAN-TUBSAT during geomagnetic storm 2015

Abstract

The purposes of this research are (1) determine the relationship between LAPAN-TUBSAT orbital elements and geomagnetic activity; (2) estimate daily drag acceleration; (3) determine the relationship between drag acceleration and geomagnetic activity. We used STK (System Tool Kit), python, and CCMC (Community Coordinated Modeling Center) interactive model to process the data. To calculate the drag acceleration, it takes data of satellite’s velocity that obtained from STK and atmospheric density. To generate atmospheric density, we used CCMC with MSISE-90 (Mass Spectrometer – Incoherent Scatter Extended 1990) and IRI (International Reference Ionosphere) atmospheric model. In addition, it takes the satellite’s position (latitude, longitude, and height – taken from STK) as input. On March 2015, geomagnetic storm index (daily Dst) had a minimum value of -105 nT on March 18, 2015. According to hourly Dst data, the minimum value of Dst reached -223 nT at 23:00 UT on March 17, 2015. Changes of orbital elements were influenced by geomagnetic storms through the Dst index. Maximum changes of semi-major axis, inclination, argument of perigee, and longitude of ascending node occurred on March 17-21, 2015 (geomagnetic storm period). Minimum change of eccentricity occurred on March 15-16, 2015 when Dst reached a maximum value. Atmospheric model is influenced most by solar conditions both during periods of calm or storm. Atmospheric density generated by MSISE-90 and IRI, both of them has 10−6 order difference. MSISE-90 is 10−16 while IRI 10−22. For MSISE-90, maximum drag acceleration reached 451,4416 m/hari2 occurred on March 17, 2015, along with a strong geomagnetic storm phenomenon. For IRI, the value of drag acceleration during peak geomagnetic storm (March 18, 2015) reached 0,000373 m/hari2 (close to the minimum value in March 2015). Drag acceleration of LAPAN-TUBSAT is linear to the Dst index with a correlation coefficient of -0,51.