by Xinhua writers Yu Fei Cheap Men's Air Max 96 SE XX Triple Black , Quan Xiaoshu and Qu Ting


JIUQUAN, June 15 (Xinhua) -- China launched its first X-ray space telescope to observe black holes, pulsars and gamma-ray bursts, via a Long March-4B rocket from Jiuquan Satellite Launch Center in northwest China's Gobi Desert at 11 a.m. Thursday.


The 2.5-tonne Hard X-ray Modulation Telescope (HXMT), dubbed Insight, was sent into an orbit of 550 kilometers above the earth to help scientists better understand the evolution of black holes, and the strong magnetic fields and the interiors of pulsars.


Through the telescope, scientists will also study how to use pulsars for spacecraft navigation, and search for gamma-ray bursts corresponding to gravitational waves.


The result of the wisdom and efforts of several generations of Chinese scientists, Insight is expected to push forward the development of space astronomy and improve space X-ray detection technology in China.


OBSERVATORY IN SPACE


Insight can be regarded as a small observatory in space, as it carries a trio of detectors -- the high energy X-ray telescope (HE), the medium energy X-ray telescope (ME) and the low energy X-ray telescope (LE) -- that cover a broad energy band from 1 keV to 250 keV, said Lu Fangjun, chief designer of the payload.


Based on the demodulation technique first proposed by Li Tipei, an academician of the Chinese Academy of Sciences (CAS), in 1993, the HE has a total detection area of more than 5,000 square centimeters, the world's largest in its energy band.


"Given it has a larger detection area than other X-ray probes, HXMT can identify more features of known sources," said Xiong Shaolin, a scientist at the Institute of High Energy Physics of the CAS.


Chen Yong, chief designer of the LE, said X-rays of lower energy usually have more photons, so a telescope based on a focusing technique is not suitable for observing very bright objects emitting soft X-rays, as too many photons at a time will result in over-exposure.


But HXMT won't have that problem, as its collimators diffuse photons instead of focusing them. "No matter how bright the sources are, our telescope won't be blinded," said Chen.


According to Zhang Shuangnan, HXMT lead scientist, the satellite's developers found that a set of HXMT high-energy detectors, originally designed to shield background noises caused by unwanted X-ray photons, especially those from behind the telescope, could be adjusted to observe gamma-ray bursts.


The creative new function pushes the satellite's observation band up to 3 MeV and will get a very good energy spectrum, Zhang said.


BLACK HOLES, PULSARS


"We are looking forward to discovering new activities of black holes and studying the state of neutron stars under extreme gravity and density conditions, and physical laws under extreme magnetic fields. These studies are expected to bring new breakthroughs in physics," said Zhang.


Compared with X-ray astronomical satellites of other countries, HXMT has a larger detection area, broader energy range and wider field of view. These give it advantages in observing black holes and neutron stars emitting bright X-rays, and it can more efficiently scan the galaxy, Zhang said.


Other satellites have conducted sky surveys and found many celestial sources of X-rays. However, the sources are often variable, and occasional intense flares can be missed in just one or two surveys, according to Zhang.


New surveys can discover either new X-ray sources or new activities in known sources. So HXMT will repeatedly scan the Milky Way for active and variable celestial bodies emitting X-rays.


"There are so many black holes and neutron stars in the universe, but we don't have a thorough understanding of any of them. So we need new satellites to observe more," Zhang said.


Black holes remain a mystery. One of their many secrets is why they get "angry."


"Black holes will be the focus of our observation since they are very interesting, and can generate various types of radiation, including X-rays and high energy cosmic rays, as well as strong jets," said Zhang.


So far about 20 black holes have been found in our galaxy. "We hope our telescope can discover more black holes. We also hope to better observe the black holes already discovered."


If a black hole does nothing, it cannot be found. But if matter falls into a black hole, it is accelerated and heated during the process, emitting X-rays. Scientists might learn more about the characteristics of black holes from the X-rays.