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"Penelitian tentang probabilitas keterkaitan antara semburan radio matahari tipe II dan lontaran massa korona (Coronal Mass Ejection/CME) menunjukkan bahwa dari 663 kali kejadian semburan radio tipe II terdapat 527 (79.49%) berasosiasi dengan kejadian CME, sebaliknya hanya 5.28% kejadian CME yang berasosiasi dengan kejadian semburan radio tipe II. Durasi berlangsungnya semburan radio tipe II cenderung semakin panjang dengan peningkatan kecepatan CME, keduanya memiliki korelasi walaupun hanya memiliki angka korelasi yang rendah (0.28). Kedua fenomena tersebut terjadi karena lewatnya muka gelombang kejut ketika ada peristiwa flare matahari, dan ditemukan bahwa CME yang berasosiasi dengan semburan tipe II terbanyak (25.43%) memiliki kecepatan antara 400 km/detik dan 600 km/detik."

"Untuk membuat prakiraan siklus matahari ke-24, dikembangkanlah metode nonlinier fitting yang telah dikembangkan sebelumnya oleh LAPAN. Dengan menentukan parameter-parameter persamaan model yang telah dibuat dan melakukan uji coba model tersebut untuk merekonstruksi siklus 21-23, dapat diketahui bahwa model ini dapat digunakan untuk memperkirakan siklus 24 matahari. Prakiraan siklus ke-24 matahari dibuat menggunakan persamaan hasil non-linier fitting melalui penggunaan data terbaru bilangan sunspot bulanan dan memadukannya dengan hasil temuan terbaru tentang prakiraan siklus ke-24. Siklus 24 diperkirakan akan lebih rendah dari siklus 23 dan mencapai puncaknya pada bulan September 2012."

"Satellites which orbit under influence of gravity can be expressed as a set of orbital elements which can be regarded as time - dependent fixed entities. In general, two-body approach is enough, but in reality there are saome gradual shifts which can't be ignored. There are some disturbance which occur in satellites which orbitting the earth so the performances of these satellites are not as good as expected. The main cause of this perturbation are the existence of third body, imperfection of earth's symetry, atmospheric drag, and solar radiation pressure. The effect of perturbation to the satellite orbit can be catagorized according to the periodicity of this perturbation. Secular variation shows variations which change the orbit linierly in time, so in the long run it can affect the orbit of this satellite. The most dominant cause of secular variation is the aspherity of the earth. Short term variation is a periodic variation which occur in the orbit in which the time scale is shorter than the orbital period. Long term variation is a periodic variation which occur in the orbit in which the time scale is longer than the orbital period. Atmospheric drag depends linierly on the atmospheric density and High Earth Orbit Satellites are more influenced by solar radiation pressure."

"Cosmic rays is energetic particles from space. These particles to the lower atmosphere and influence the earth's global electricity and magnetism. Cloud forming can be accelerated by the electricity and cloud thermodynamic. These basic knowledge are used in making correlation analysis between cosmic ray and total cloud/upper cloud cover in the region of Indonesia in the period 1979 to 1995. The analysis of the correlations in this report including total correlation, annual correlation, and the correlation in maximum and minimum solar cycle."

"The virtual temperature (Tv) retrieval with good time and spatial height resolution (in a few minutes and a few hundred meters in altitude height) until now not yet done by many people. It is caused since radiosonde launch only one to fourth times in a day. Therefore, it is needed the special remote sensing instrument that specially arranged to solve this problem. One of them is the Radio Acoustic Sounding System (RASS) operated by LAPAN and Research Institute for Sustainable Humanosphere (RISH), Kyoto University, Japan during the Coupling Processes Equatorial Atmosphere (CPEA) campagin I from 10 April to 10 May, 2004 has already done at LAPAN Kototabang station. By using the statistical analysis, it is obtained a good correlation between Tv RASS and Tv radiosonde, especially on 29 April 2004 with the average of correlation coefficient is about 0.98. It shows that Tv RASS is significant and valid for advance analysis, such as for determination of relatif humidity value RH)"

"Perbandingan antara curah hujan konvektif hasil simulasi Model Sirkulasi Umum Atmosfer (Atmospheric General Circulation Model, atau disingkat AGCM) dengan data pengamatan telah dilakukan. Model Sirkulasi Umum yang digunakan adalah CSIRO9 (Commonwealth Scientific and Industrial Research Organization), sedangkan data pengamatan diperoleh dari satelit TRMM (Tropical Rainfall Measuring Mission). Data yang dibandingkan adalah curah hujan konvektif rata-rata bulan Januari s.d Desember tahun 2004. Hasil perbandingan menunjukkan bahwa pola-pola distribusi curah hujan hasil simulai model dan pergerakannya secara umum mengikuti pola-pola yang diperlihatkan data pengamatan, namun secara rinci memperlihatkan perbedaan-perbedaan, yang diperkirakan antara lain akibat dari resolusi model yang relatif rendah. Peningkatan resolusi model diperlukan untuk meningkatkan ketepatan prediksi di wilayah benuamaritim Indonesia."