Search

We analyzed dose rate data of space neutron and gamma radiation during several flight with various destinations, i.e. Jakarta – Kupang, Kupang – Jakarta, Jakarta – Pontianak, and Pontianak – Jakarta. Data were collected using personal radiation dosimeter (RadEye for neutron and Dosicard for gamma radiation) during flights from take off until landing at the destination airports. As expected, the higher the aircraft from sea level, the radiation received are higher also, but the behaviour of the neutron and gamma radiation are different. The neutron radiation received are more erratic compared with that of the gamma radiation. We found the correlation between the height of the aircraft and neutron and gamma radiation dose rates with correlation coeficient values of 0.89, 0.86, 0.90, 0.87 respectively for neutron radiation and 0.91, 0.95, 0.84, 0.88 respectively for gamma radiation. We found the empirical relations between latitude and dose rates of neutron and gamma radiation in the height of 35.000 feet from the sea level as Dn = −0.034 Lat + 1.036 for neutron dose rates and Dg = −0.027 Lat + 0.636 for gamma radiation dose rates. [ABSTRACT FROM AUTHOR]

We present geometrical and kinematical analysis of Moreton waves and EIT waves observed on June 3, 2012 and Moreton waves observed on July 6, 2012. The Moreton waves were recorded in Hα images of Global Oscillation Network Group (GONG) archive and EIT waves obtained from SDO/AIA observations, especially in 193 nm channel. The observed wave of June 3 has angular span of about 70 with a broad wave front associated to NOAA active region 11496. It was found that the speed of the wave that started propagating at 17.53 UT is between 950 to 1500 km/s. Related to this wave occurrence, there was solar type II and III radio bursts. The speed of the EIT in this respect is about 247 km/sec. On the other hand, the wave of July 6 may be associated to x1.1 class flare that occurred at 23.01 UT around the 11514 active region. From the kinematical analysis, the wave propagated with the initial velocity of about 1180 km/s which is in agreement with coronal shock velocity derived from type II radio burst observation, v ≈ 1200 km/s. [ABSTRACT FROM AUTHOR]

Transit Venus was observed in LAPAN Biak using a portable telescope with a diameter of 103 mm and recorded using ImagingSource CCD video camera. The backdrop effect was observed during the beginning of transit. This work tries to analyze this backdrop effect observed during this expedition. [ABSTRACT FROM AUTHOR]