Mizusawa Observatory began with latitude observations.

1765	Swiss mathematician Euler predicts that the Earth's polar motion period is 305 days.
1884	German astronomer Kustner confirms latitude change due to polar motion.
1899	American astronomer Chandler also detected polar motion from past observational data and determined that the period was 428 days.
1895 -1901	Observation of latitude changes at Tokyo Astronomical Observatory
1895	The establishment of a latitude observatory at the same latitude for polar motion research was proposed at the International Geodesy Association General Assembly.
1898	A five-year international joint observation period was decided in 1900.
1914	In addition to earthquake and meteorological observations, which had been conducted since 1901, observations of anomalous refraction near the observation room were also started.
1920	Beginning of balloon-based observations of upper atmosphere air currents.

Expansion of the international latitude observation project and investigation into the cause of the z term.

1920	The temporary latitude observatory becomes the latitude observatory.
1922	Mizusawa becomes the central station for the International Latitude Observatory (until 1936)
1926	Jefferies uncovers the existence of Earth's fluid core through seismic analysis.
1936	Lehmann discovered that the core is divided into an outer core and an inner core.
1938	Kimura proposes extending the overnight observation time to six hours at the General Assembly of the International Astronomical Union.
1955	Overnight observation time extended to 6 hours.
1957-1961	Coefficients necessary for understanding the fluid core are sought and a theory is constructed.
1962	Mizusawa becomes the central station for the International Polar Motion Observation Program (until 1987)
1970年	6m millimeter wave radio telescope completed on Mitaka campus.
	Kojiro Wako discovered that the Z term is caused by a resonance phenomenon in which the fluid core and its outside move independently.
1971	International Astronomical Union Symposium "Earth Rotation" held (Morioka/Mizusawa)
1977	Tetsuo Sasao developed a method to obtain the response of the fluid core more easily and efficiently.
1978	Observation of Earth's gravity, tilt and strain begins at Esashi Earth Tide Observatory.
1980	Polar motion unified recalculation results publication.

Research and studies begin on the development of devices (telescopes, etc.) using radio interference techniques that will lead to the VERA project.

1975	At the General Assembly of the International Geodesy Association, it was decided that the organization should be established quickly based on new technology and that a thorough comparison of the old and new systems should be carried out. Based on this, the study of a highly accurate ultra-long distance interferometric device using space technology began.
1983	Drafted the Very Long Baseline Interferometry System for Earth Rotation and Reference Frame (First VERA *1 Project)
1985	Nippon Telegraph and Telephone Public Corporation Yokosuka Electrical Communication Research Laboratory 3.3m parabolic antenna moved to Mizusawa and technical acquisition took place.
	Mizusawa Latitude Observatory believes it is important to have VLBI and has proposed a VLBI plan for the Earth's rotation and reference frame.
1985	The Longitude and Latitude Study Group presented the use of VERA as a direction for radio astronomy using VLBI technology.
1986 December 2nd	Visual observations using a visual zenith telescope ended.
1987	Agreement concluded with the Ministry of Posts and Telecommunications Radio Research Laboratory (now the National Institute of Information and Communications Technology), developer of Japan's VLBI system K-3.
	In cooperation with the Nobeyama Radio Observatory of the Tokyo Astronomical Observatory (now the National Astronomical Observatory of Japan) and the Geospatial Information Authority of Japan, the Ministry of Posts and Telecommunications Radio Research Laboratory Kashima Branch participated in IERS using the 26m diameter VLBI antenna in Kashima.
1988	The International Astronomical Union (IAU) and the International Union of Geodesy and Geophysics (IUGG) established the International Earth Rotation Service (IERS) to replace the International Polar Motion Measurement Service (IPMS) and the International Bureau of Time (BIH).
1988July 1st	The Tokyo Astronomical Observatory, the Latitude Observatory, and the Nagoya University Research Institute of Atmospherics were integrated to form the National Astronomical Observatory.
1988	With the establishment of the National Astronomical Observatory, it was reorganized into the Earth Rotation Research Division and Mizusawa Observatory.
	From here, we began our activities with the main pillars of Earth rotation, VLBI radio astronomy, and Earth and planetary science.
	The 6m millimeter wave radio telescope was relocated from Mitaka to Mizusawa.
1989	The 6m millimeter wave radio telescope was relocated to Nobeyama.
1992	Construction of 10m radio telescope.
	Construction of Takahagi 32m radio telescope.
1993	Observations using a photographic zenith tube ended.

The VERA project begins in earnest.

1995	The Terrestrial VLBI Unified Plan Working Group unified the domestic plans into the new VERA*2 and obtained approval from each relevant committee.
1996	The two-beam relative VLBI method is proposed.
1998	Initial VERA-related budget approved in supplementary budget.
1999	Supplementary budget approved for Mizusawa, Iriki, and Ogasawara stations.
	Mounting section at Kawatetsu Machinery Mizushima Works, temporary assembly and testing at Tamba Engineering, and drive control manufacturing and testing at Mitsubishi Electric Communication Equipment Works.
2000	Ishigakijima Station budget approved in supplementary budget. [Technology development, etc.] Construction of phase compensation observation function using two beams. Improvement of transmittance by improving antenna feedome. Development of K/Q band receiver. Development of S/Z band receiver. AD converter. Optical data transmission. Digital filter. Digital data recording.
2001 January 28th	Kagoshima University and the National Astronomical Observatory of Japan signed an agreement to jointly construct and operate VERA.
2001	Construction of Mizusawa Station Construction of Iriki Station Construction of Ogasawara Station VERA 3 stations (Mizusawa Station, Iriki Station, Ogasawara Station) completed.
2001 October	First light from VERA Mizusawa Station.
2001 December	First light of VERA Iriki Station.
2002 February 15th	First light of VERA Ogasawara Station.
2002 February 20th	First fringe detection between Mizusawa and Iriki stations.
2002 March 21st	Successful simultaneous tracking of celestial objects with two beams at Iriki Observatory.
2002	VERA Ishigakijima station completed.
2002 May 29th	First fringe detection using two beams between Mizusawa Station and Iriki Station.
2002 June 17th	First light from VERA Ishigakijima Station.
2002 December	VERA's first successful imaging of quasar 4C39.25
2003 May	Fringe detection in all bands and stations.
2003 October	First users meeting held.
2003 December	Trial shared use begins.
2004	Phase compensation imaging successful.
2004 February	First round of applications begins
2004 September	All stations can be remotely controlled from Mizusawa.
2004 November	Successful geodetic observation between VERA stations.
2005 July 7th	Signing ceremony for memorandum of understanding on joint development of VLBI correlator between Japan and Korea.(PDF)
2005 August	High school students discover water maser object at Churaumi Research Center.
2005 November	Start daily operations
2005 November	Test observations conducted based on university-college VLBI.
2005 December	Successful fringe detection in test observations between the optical coupling station (Geospatial Information Authority of Japan Tsukuba 32m telescope) and the VERA station.
2006	International recruitment begins
2007 April 4th	Notification of decision to transfer the former Latitude Observatory main building to Oshu City.(PDF)
2007 July 11th	VERA successfully measures precise distances to celestial objects.
2008 November 1st	First fringe detection between VERA and KVN.

VERA technology is established and is expanding into a variety of research results.

2010 November 26th	Accurately determine the distance to the Sagittarius Arm.
2012 September 18th	Supermassive black hole jet seen with the highest visual acuity ever seen.
2014	First open-use observation of KaVA.
2014 July	Successful imaging of celestial objects during the day with radio telescopes including VERA
2014 November	Japan-Korea joint VLBI network KaVA detects 44GHz methanol maser for the first time using VLBI
2015 February	KaVA successfully images active galactic nuclei in detail
2016 May	Japan-Korea Joint VLBI Observation Network Begins Full-Scale Operation - High-Quality Two-Color Imaging of Silicon Monoxide Maser around WX Pisces Successfully Obtained.
2018 September 6th	Japan, South Korea and China Sign Agreement to Operate the East Asia VLBI Network.
2018 October	East Asia VLBI Network (EAVN) open observation begins.
2019 April 10th	First ever image of a black hole captured!
2020 July	First results from the Japan-Korea VLBI Network KaVA large-scale star formation observation program: A look at massive baby stars spewing high-velocity gas outflows.
2020 August	20 years of VERA project results summarized − Higher accuracy in astronomy achieved in 120 years of NAOJ Mizusawa history −
2021 April 14th	Simultaneous multi-wavelength observations reveal the activity of the M87 supermassive black hole and its surrounding structure − Ground-based and space-based telescopes join forces −
2022 May 12th	First successful image of black hole at the center of the Milky Way.
2023 September 28th	Precessing M87 jet outlet − New evidence of “rotation” of a massive black hole −