In 1918, H.D. Curtis of the Lick Observatory discovered the 1st "cosmic jet" in the nucleus of the nearby active radio galaxy Messier 87 (M87). During the last four decades, the structure and dynamics of the M87 jet have been extensively studied from 10 to 107 Schwarzschild radii in broadband (from radio through to optical and X-ray) wavelengths. The jet exhibits superluminal motions, indicating an acceleration of bulk flows up to relativistic speeds in the parabolic stream, and travels well beyond the physical extent of its host galaxy as seen in observations.
X-ray observations toward M87 reveal that expanding lobes interact with the interstellar medium (ISM), indicating radio-mode AGN feedback is acting in the central cooling core of the host elliptical galaxy. We presumably observe a site of co-evolution between the central supermassive black hole (SMBH) and its host galaxy. Hot X-ray gases at around the Bondi radius tell us the nature of radiatively inefficient accretion flows, which are also explored by recent sub-mm polarimetry observations. Very high energy emissions from M87 are often observed in pre- and current-Fermi era and several ideas for locating gamma-ray flares have been suggested; near the black hole magnetosphere and/or at the far distant place of the HST-1 complex.
One of the most exciting issues in advancing astronomy for the coming decade is to prove the existence of black holes through direct evidence using sub-mm VLBI observations. The combination of an extremely massive black hole in a range of three to six billion solar masses and its proximity to Earth has lead to a special interest with M87 in this regard. Under the international collaboration with SAO, MIT Haystack observatory, and NRAO, the Academia Sinica Institute of Astronomy & Astrophysics (ASIAA) is now conducting the Greenland telescope (GLT) project to image the shadow of the SMBH in M87 with a few tens of micro arcsecond resolution, thanks to VLBI networks. GLT Project is planning to ship the telescope components to Greenland in 2016, and the ALMA Phase-up capability is coming on line soon. Several key elements to understand the AGN central engine in M87, such as the innermost jet and black hole accretion flows on the scale of the event horizon, will also be unveiled by the GLT. Thus, M87 has been providing numerous interesting topics to astronomers during the last century and will continue to do so this century.
The 4.5-day workshop (with a half day excursion) will be hosted by ASIAA. The last meeting on M87, entitled "The Radio Galaxy Messier 87", was held at Ringberg, Germany in 1997. During the last two decades, we have learned more exciting topics about M87. Therefore, this is a good time to discuss M87 again with the deeper understandings we have gleaned during the last two decades. We have contacted a wide range of experts in related fields to get their support for organizing this meeting and have been collecting supportive replies from SOC members who will guide the direction of this workshop. It will provide a great opportunity to enhance active interactions among local and oversea astronomers, as well as stimulating students and young researchers in various fields.
M 87, one of the most popular sources in nearby radio loud AGNs, will be extensively discussed from the black hole to galactic scales. We also expand our topics towards future sub-mm VLBI observations of the central engine of M87, our galactic center Sgr A*, and other nearby low-luminosity AGNs (LLAGNs). Therefore, we expect a broad interest from the large communities in both theory and observations from radio to γ-ray bands.
- Supermassive black holes; the mass, the spin, and direct imaging of their silhouette
- Black hole accretion; from the Bondi radius to the event horizon scale
- Black hole jets; from the event horizon to the galactic scale
- High energy emissions; their sites and mechanisms
- Co-evolution of galaxies and black holes; the AGN feedback
Four internationally renowned keynote speakers have been invited to promote the workshop.
Director, Kavli Institute for Astronomy and Astrophysics
University Chair Professor, Peking University
Co-evolution of Galaxies and Black Holes Watch Video
Associate Dean for the Sciences in the College of Liberal Arts and Sciences, University of Virginia
Professor, Department of Astronomy, University of Virginia
Black Hole Accretion Watch Video
Thomas Dudley Cabot Professor of the Natural Sciences, Harvard University
Senior Astronomer, Harvard-Smithsonian Center for Astrophysics
Black Hole Jets Watch Video
Christine Jones Forman
President-elect, The American Astronomical Society
Senior Astrophysicist, Smithsonian Astrophysical Observatory/Lecturer on Astronomy, Harvard University
Cosmic Feedback from Black Holes Watch Video
|We are sorry to announce that the keynote presentation by Prof. Roger Blanford (Stanford) has been cancelled due to scheduling conflicts with the Crafoord days (Prof. Blandford has been awarded as one of the 2016 Crafoord prize recipients).|