The 6th China-Chile Bilateral Conference for Astronomy Held in Chile

From November 6th to 10th, the 6th China-Chile Bilateral Conference for Astronomy was held in Puerto Varas, Chile. Over 80 experts, young scholars, and students from more than 30 astronomy research institutions, including the Chinese Academy of Sciences, various Chinese universities, and Chilean astronomy institutions, participated in the conference. They engaged in in-depth discussions on research achievements, the latest developments in China-Chile cooperation, and future collaboration opportunities. This conference was jointly organized by the National Astronomical Observatories of the Chinese Academy of Sciences (CAS, NAOC)/Chinese Academy of Sciences South America Center for Astronomy (CASSACA) and the Chilean Astronomical Society (SOCHIAS). The conference was co-chaired by Prof. Jiasheng Huang from NAOC and Prof. Diego Mardones from the University of Chile.

Gongbo Zhao, Deputy Director of NAOC and Director of CASSACA, and Bruno Días, President of SOCHIAS, delivered opening speeches and welcomed the conference attendees. The conference covered the latest research results in various research areas, including solar system objects, protoplanetary disks, star formation, interstellar medium and astrochemistry, extrasolar planets, stars and star clusters, galaxies, active galactic nuclei, and cosmology, as well as theoretical astrophysics, numerical simulations, big data astronomy, astronomical instruments and equipment, and observatory construction. The conference specially invited astronomers to present the astronomical scientific research achievements and the construction of astronomical observatories and equipment in both China and Chile under the cooperation between the two countries. The invitees included professors Licai Deng, Zhaohui Shang, and Jianrong Shi, from NAOC; professor Zhenya Zheng, from the Shanghai Astronomical Observatory, CAS; professor Ezequiel Treister, from the Pontifical Catholic University of Chile; Dr. Daniela Estefanía Olave Rojas, from the University of Talca; Dr. Richard Lane, from Bernardo O’Higgins University; Dr. Denise Riquelme, from La Serena University; and professor Bin Yang from Diego Portales University. Professor Guido Garay from the University of Chile opened the meeting by reviewing the scientific achievements and excellent talents cultivated in the past ten years of astronomical cooperation between China and Chile. Professor Junfeng Wang from Xiamen University provided a summary of the conference and offered a vision for future China-Chile astronomy cooperation.

This bilateral meeting serves to promote the exchange of astronomy between China and Chile, deepen mutual understanding and trust, expand the influence of Chinese astronomy in Chile, and lay the foundation for more effective China-Chile cooperation in the future. During the conference, astronomers from both China and Chile actively explored common ground for collaboration, fostering in-depth discussions and seeking new points of collaboration. This sets the stage for the rational and efficient utilization of research resources from both sides, focused on key research directions, and the preparation for the early production of significant scientific results in the future.

The Fifth China-Chile Bi-lateral Astronomy Science Meeting was successfully held in Kunming during Jan. 23-26, 2019

Meeting group photo

In order to promote the communication and collaboration between astronomy communities of China and Chile, sponsored by Chinese Academy of Sciences (CAS), National Natural Science Foundation of China (NSFC), National Astronomical Observatories, CAS (NAOC), the “Fifth Chile-China Bi-lateral Astronomy Science Meeting” was successfully held in Kunming during Jan. 23-26, 2019. The meeting was organized by the CAS South American Center for Astronomy (CASSACA), also known as China-Chile Joint Center for Astronomy, along with Yunnan Astronomical Observatory (YNAO).

A glance at the meeting

CASSACA is one of the overseas projects initiated by CAS to develop cooperation in science and technology with foreign countries. In February 2013, CASSACA was inaugurated at NAOC, and its Santiago office was inaugurated in October 2013 at University of Chile. The Center serves as a platform for collaboration in astronomical research and related technologies between China and South America countries. The Center helps to build international scientific teams and joint programs engaging in frontier astronomy research. The China-Chile Astronomy Workshop is a major platform to strengthen communications in astronomical research between the two countries, and has been held alternately in Chile and China. It has been proven to be successful in the past meetings of the series, prompting knowledge and information exchange between astronomers, and initiating collaborative projects and joint programs.

Hui Sun, Director of America and Oceania Department, Bureau of International Co-operation, CAS, addressing the meeting
Suijian Xue, Deputy president of NAOC, addressing the meeting
Jiasheng Huang, Chief Scientist of CASSACA, hosting the meeting
Patricio Rojo , Chairman of SOCHIAS, introducing the astronomy in Chile
Participants discussing

Around 70 participants attended this Meeting, including experts, young scientists and students, coming from more than 20 institutes of China, Chile, and other countries. Professor. Jiasheng Huang, Chief Scientist of CASSACA, and Professor Jinming Bai, president of YNAO, offered their welcome as the hosts; Hui Sun, Director of Division of America and Oceanian Affairs, Bureau of International Cooperation, CAS and Suijian Xue, Deputy Director General of NAOC, both addressed the meeting; Dr. Wei Wang, Deputy Director of CASSACA, introduced the current status and future prospects of the Center; Professor Patricio Rojo, Chairman of Astronomical Society of Chile (SOCHIAS) and other Chilean astronomers expressed high expectations for the Chile-China cooperation, and gave a lot of suggestions and comments. At this Meeting, directors or their representatives of nearly all major astronomical observatories/departments of China and Chile summarized the major research areas and current activities of their institutions, including detailed talks on recent research highlights. During the four-day workshop, astronomers from both countries communicated cordially and comprehensively, reviewing the existing ties and finding opportunities for future collaborations. The bilateral meeting is recognized as an important catalyst for Chile-China astronomy communications, and a useful model for CAS to advance international cooperation widely.

CASSACA scientist reveals the connection between radiation and shape of circum-nuclear materials around super-massive black holes

[Dr. Claudio Ricci, a CAS-CONICYT Postdoctoral Fellow in astronomy,  led an important paper inNature》on September 27th 2017, in which he reported recent major progress regarding how radiation feedback controls the shape of close environment around super-massive black holes, drawn from a multi-band survey of a sample of black holes selected in the hard X-ray band.]

A black hole is a place in space-time where gravity pulls are so strong that even light cannot get out, it is therefore “black” in any bands. The theory of general relativity predicts that a sufficiently large and dense mass would deform space -time and give birth to a black hole. Despite its invisible interior, a black hole can be indirectly inferred and investigated at various wavelengths through its interactions with the surrounding and in-falling materials.

It is known for decades that very heavy black holes inhabit the centers of galaxies (including our own galaxy, the Milky Way), but are hidden by gas and dust. Some of these black holes can “eat” materials from their environment, and emit a lot of light during this process. Most of these “luminous” black holes are surrounded by large amount of gas and dust, distributed in a doughnut-like structure. Such a structure could resemble a pantry, which guarantees that the black hole can keep eating, radiating and growing. However, it is not known where exactly this material is located, and what the relationship is between light produced by the black hole and the dusty gas.

In order to address this long-standing issue, Dr. Claudio Ricci, a postdoc fellow supported by Chinese Academy of Sciences South America Center for Astronomy (CASSACA), and his collaborators made use of observations carried out in the X-ray band, similar to what is typically used for radiographies in hospitals. With each observation performing these “space radiographies”, they could measure the amount of material around the black hole, and then study its evolution.

This project started in 2013, and it took the authors many years to create the large database used for their research, using data from space telescopes as well as ground-based observatories, such as those in Chile. The Chilean telescopes were extremely important for measuring the properties of the black holes, and in particular, for “weighing” their masses. The main X-ray instrument used was the NASA satellite Swift, but also data from the satellites XMM-Newton of ESA, Suzaku of JAXA, and another NASA telescope, Chandra, were used. In the optical band the facilities used include the Sloan Digital Sky Survey, the UK Schmidt telescope, Gemini, CTIO, DuPont and SAAO.

With this work, Ricci and collaborators discovered the process that controls the interaction between light produced by the black hole and the gas that surrounds it, and showed that most of the material around black holes is located close to it. The authors found that, when the black hole emits a lot of light, this light pushes away the material from its vicinity; in other words, the gas can “evaporate” because of the large amount of energy released by the material falling rapidly onto the black hole. This could also mean that, if the black hole “eats” too rapidly, the energy produced could destroy the “food” available for the future.

It is a major step forward to reveal a clear picture of the connection between radiation feedback and the surrounding material’s shape. “The next step will be to further understand the details of this behavior, and what happens to the material that is pushed away from the black hole”, said Dr. Ricci, the leading author of this work.

Figure 1. Artistic impression of the gas and dust surrounding an accreting supermassive black hole. Taken from NASA/JPL/Caltech.

Figure 2. Schematic representation of the material surrounding supermassive black holes for different ranges of Eddington ratio. The Eddington ratio is the ratio between the bolometric and the Eddington luminosity, where the latter is defined as the luminosity at which the radiation pressure from a source, in this case the accreting SMBH, balances the gravitational attraction. Taken from Ricci et al. (2017, Nature Letter).

CAS Vice President Tieniu Tan Visits Chile

Dr. Tieniu Tan, Vice President of Chinese Academy of Sciences (CAS), visited Chile from May 6th to 8th, 2016, as invited by the Chilean Comisión Nacional de Investigación Científica y Tecnológica (CONICYT), the University of Chile and the Chinese Academy of Sciences South America Center for Astronomy (CASSACA). Dr. Xiaoyu Hong (Director General of Shanghai Astronomical Observatories, CAS), Xiaoou Chen (Commissioner of Science and Technology, Chinese Embassy in Chile), Zhong Wang (Director of CASSACA), Wei Wang (Deputy Director of CASSACA) and Dr. Meng Su (MIT) accompanied his visit.

 

In the morning of May 6th, Dr. Tan met the new CONICYT director Dr. Mario Hummuy and Chilean Senator Dr. Guido Girardi. They discussed potential collaborations between the two countries in astronomy and other aspects of science and technology. Afterwards, Dr. Tan visited the China-Chile Astronomical Data Center (CCADC) and offered his suggestions for its long-term development. CCADC is the first major collaborative project led by CASSACA. Its aim is to enable Chinese and Chilean astronomers to better process astronomical data obtained from large telescopes.

 

In the afternoon, Dr. Tan visited the Department of Astronomy at the University of Chile. There, he expressed gratitude to director Dr. Guido Garay for the department’s help in the development of CASSACA and discussed future plans for the Center. Dr. Tan then visited the CASSACA office and was introduced to its staff and researchers. Dr. Tan applauded the significant achievements of CASSACA during the past three years, and he encouraged the staff in their efforts to build international scientific cooperation, to drive cutting edge astronomical research, and to develop the Center as a platform for China-Chile collaborations in astronomy and other areas of research. In addition, Dr. Tan met the Chinese Ambassador in Chile, Mr. Baorong Li, and the President of the Chilean Academy of Sciences, Madam Maria Teresa Ruiz, and exchanged ideas with them regarding China-Chile collaborations and CASSACA.

 

On May 7th and 8th, Vice President Tan went to northern Chile to visit the Atacama Large Millimeter/sub-millimeter Array (ALMA), which is assembled on a 5,060 meter-high plateau, as well as three telescopes dedicated to Cosmic Microwave Background (CMB) research. These were the Atacama Cosmology Telescope (ACT), the Cosmology Large Angular Scale Surveyor (CLASS), and the POLARBEAR telescopes, all of which are assembled on a 5,200 site nearby. Together, these facilities represent the state-of-the-art science and technology in radio astronomy and are the results of a wide-range of international collaborations. Dr. Tan’s visit is among the first that CAS leaders made to the 5,000+ meter sites in Chile.

 

ALMA is an astronomical interferometer of radio telescopes built collaboratively by several institutions from Europe, the United States and East Asia. It consists of 66 12-meter and 7-meter diameter radio telescopes, observing at millimeter and submillimeter wavelengths, with a resolution of up to 0.01 arcsec. ALMA is expected to be able to provide insights on star birth during the early universe and detailed imaging of local star and planet formation. ALMA is located in the Atacama Desert of Northern Chile, on the Chajnantor plateau. The location is one of the driest sites in the world and very suitable for mm and submm observations. After about 15 years of construction, costing US$1.4 billion, ALMA began full operation in March 2013. The observatory has since attracted close attention from astronomers from all nations and led to various new scientific discoveries.

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CAS Vice President Tieniu Tan Visits Chile

CASSACA Council Meeting held in Beijing

On December 18, 2015the Council Meeting of the Chinese Academy of Sciences South America Center for Astronomy (CASSACA) was held in  National Astronomical Observatories, Chinese Academy of Sciences (NAOC). Prof. Zhongli Ding, Vice President of CAS & Director of the Council, attended the meeting and gave important suggestions and guidance to CASSACA. There are more than 30 attendees coming from CAS administration divisions, the institutes in CAS Observatory system and Universities. 

Prof. Zhong Wang, Director of CASSACA, reported the overall progress and achievements of the Center obtained in 2015. Prof. Jiasheng Huang, Chief Scientist of CASSACA, specially introduced the progress in research and scientific programs in the past. Then the Council gave full affirmation on the achievements and progress by the Center. The Council gave practical guidance and suggestions to the Center’s development and future plans. Two new members were approved to join the Council.  

CASSACA has achieved remarkable results and progress in the past, over its collaborations with Chilean institutions and scientists, on the scientific researches, programs and projects. Especially, the CASSACA set up the China-Chile astronomical data center with cooperation with Universidad Tecnica Federico Santa Maria of Chile and Huawei company of China. Prime Minister Keqiang Li and Chilean President Michelle Bachelet witnessed the signing ceremony of the data center in May 2015. The system run stably and went into the stage of software debugging and commissioning since November 2015. 

CASSACA was set up in 2013 and has been playing an important role on the international collaborations in Astronomy between China and Chile together with other South America countries. 

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COUNCIL MEETING
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GROUP PHOTO

Major Chinese media visit ALMA and ESO Paranal observatories

[Preface: Since its inauguration in 2013, the Chinese Academy of Sciences’ South America Center for Astronomy (CASSACA) initialized several research collaborations between China and Chile, attracting broad interests of the national and international media, and from the general public. Especially after both Premier Li Keqiang’s and Chilean President Michelle Bachelet attended a signing ceremony of the agreement on building the China-Chile Joint Astronomical Data Center on May 25, 2015, the topics of astronomy in Chile has drawn even more attention. Recently, we made arrangements for journalists from several major Chinese news media to visit two international observatories in northern Chile, for an in-depth look at astronomical research activities in the Southern Hemisphere. ]

Journalists from local stations of the Xinhua News Agency, People’s Daily newspaper, and China Radio International visited ALMA (the Atacama Large Millimeter/sub-millimeter Array) and ESO (European Southern Observatories) Paranal, two of the largest international observatories in northern Chile, on 16-18 July 2015. During the visits and through interviews of on-site astronomers and employees, they had witnessed frontier research activities at the first-class international observatories, and gathered a lot of valuable first-hand information. CASSACA Director Wang Zhong and Deputy Director Wang Wei accompanied the visits and participated in the outreach activities.

The media group first went to ALMA Observatory on the 17th, where they visited the telescope control room, laboratory, working and living areas, and interviewed the person in charge of the station as well as front-line staff, who demonstrated the huge truck made specifically for transporting the antennas. Then they arrived at the antenna array on the 5000-meter-high plateau, equipped with supplies of oxygen, after given a medical check-up in accordance with the provisions for high-altitude environment. The large-scale modern scientific facilities, along with the magnificent natural scenery, highlight the importance of astronomical research, and illustrate the great contributions of scientists and other staff. On 18th July, at 2600m-high Paranal Observatory, the media visited the giant optical and infrared VLT 8-meter telescopes. The journalists learned about the parameters of telescopes and instruments, and the ongoing research programs carried out by the observers. They also had the opportunity to watch the entire procedure of telescope dome opening, instrument testing and preparing for observations. The dedication and professionalism of the staff, along with the advanced site management and operations, impressed them, just like the excellent sky conditions at the observatory. In the telescope control room, reporters had a light-hearted interview with Dr. Yang Bin, formerly of the National Astronomical Observatory, Chinese Academy of Sciences, who was on-duty as a night astronomer working for ESO. The professionalism, passion for astronomical observations, perseverance and dedication of this young female astronomer won their admiration.  Continue reading

CASSACA to co-sponsor a conference on “The Soul of High-mass star formation”

CASSACA is co-sponsoring a conference on “The Soul of High-mass star formation”, which is to be held on March 15-20, in Puetro Varas, a beautiful port city in South Chile.

During the last decade many large-scale surveys (e.g. GLIMPSE, ATLASGAL) led to the identification of massive star formation regions in their earliest stages in our Galaxy. These have been observed with new instruments, in particular massive Herschel data has been taken to characterize physically and chemically the most embedded sources on moderate to large spatial scales. Today, when ALMA will soon begin full operations opening new windows in frequency, chemistry, spatial resolution, and sensitivity, it is timely to discuss our current understanding and open questions on massive star formation.

For more, please visit http://www.das.uchile.cl/star-formation.

 

CASSACA to co-sponsor the MODEST15 meeting in Chile

CASSACA is co-sponsoring 15. meeting of the MODEST community (MODEST15) in Departamento de Astronomia at the Universidad de Concepcion, in Concepcion, Chile at the 2nd – 6th of March 2015.

The aim of this meeting is to provide a comprehensive software framework for large-scale simulations of dense stellar systems, within which existing codes for dynamics, stellar evolution, and hydrodynamics can be easily coupled and compared to reality.  For more, please visit http://www.astro-udec.cl/modest15/index.html.

MODEST15

The 4th Chile-China Astronomy Science workshop

In order to promote the communication and collaboration between astronomy communities of Chile and Chile, the 4th China-Chile Astronomy workshop will be held in Guangzhou, on Dec 7 – 10, 2014.

Guangzhou, the capital of the Guangdong Province,  is a beautiful and well developed city in China. It is China’s 3rd largest city, with a population of about 13 million, and Known as “The Goat City”. Guangzhou is also a trourist city, and have warm and comfortable weather in November.

CASSACA sincerely invite interested participants to join in the workshop and appreciate your contribution of talks. Please fill in the online early registration before September 29th, 2014, and submit your talk title and abstract before September 25th, 2014  if you wish to be considered for travel support, or before 10th October  if not. Read more at http://ccaw4.csp.escience.cn.