Indonesian Astronomers Set Sights on New Observatories

Astronomers are studying the feasibility of constructing two observatories in the central and eastern parts of Indonesia, where the sky is still relatively free from light pollution.

Hakim Luthfi Malasan, an astronomer from the Bosscha Observatory near Bandung, told the Jakarta Globe on Friday that the two planned observatories could provide a number of direct benefits to society, such as the ability to sight the thin crescent of the new moon that determines the start of Ramadan

This would help end the annual debate between the country’s two largest Islamic organizations, Nahdlatul Ulama and Muhammadiyah, in determining the beginning and the end of the fasting month.

Nahdlatul Ulama uses visual computations, or hilal , to determine the dates, while Muhammadiyah uses hisab , or astronomical computations.

Emmanuel Sungging Mumpuni, a space and solar system researcher from the National Institute of Aeronautics and Space (Lapan) agreed that would be one of the benefits gained from constructing new observatories.

“[The observatories] would also be part of space weather studies and would acquaint people in other parts of Indonesia with astronomy,” Emmanuel said.

Hakim, who is also a lecturer at the Bandung Institute of Technology (ITB), said “it could also widen the observing window for the study of celestial objects since we have three time zones in our country.”

He said Indonesia currently only had one observatory, Bosscha in Lembang, West Java, and that the blinding lights from homes, businesses and streets in Bandung and its surroundings had increasingly interfered with telescopic observations.

“For the past five years we have been studying the feasibility of building an observatory in the central part of Indonesia,” Hakim said, adding that astronomers from ITB were looking at two potential sites, on the eastern foot of Mount Rinjani in Lombok, West Nusa Tenggara, and on Mount Timau, near Kupang, the capital of East Nusa Tenggara.

He said both locations had equally good sky conditions. He added, however, that after consultations with the Meteorology, Climatology and Geophysics Agency (BMKG), a possible problem with the Mount Timau site had been discovered: it is seasonally affected by dessert dust from the southwestern part of Australia, carried by subtropical storms.

Hakim said a comprehensive study would be undertaken to determine the best location for a future observatory. “The study would require on-site observations for about a year, including meteorological, geological and accessibility studies for both locations,” he said.

He added that any new observatory would require energy, transportation and telecommunication infrastructure support.

Emmanuel said Lapan had also been studying the feasibility of constructing an observatory on Biak Island, Papua.

“What we have learned so far is that the atmosphere there is in good condition and not as polluted as it is in Java. The atmospheric contents such as steam are quite good, however, this is not yet conclusive as we are still conducting studies,” he said.

The observatory would be employed to observe the sun using a hydrogen alpha telescope equipped with an optical filter to capture light in the hydrogen alpha wavelength, he said

“The most important solar dynamics are observed within that wavelength. We could do an analysis to predict if there would be any negative effects on satellite or communications systems,” Emmanuel said, adding that such studies could be used to anticipate an event such as the 1989 power blackout in Quebec, Canada, caused by solar flares.

Neither scientist could provide information regarding the budget that would be needed to finance the observatories.

“It would depend on the final results of the feasibility study,” Emmanuel said.

Hakim said that ITB astronomers were hopeful the project could start within the next three years, adding that they had talked with the State Ministry for Research and Technology and the Ministry of National Education about the proposal.

“We hope to get the full support of both ministries,” he said.

(An interview with The Jakarta Globe).