We present the first astrometry catalog from the Japanese VLBI (very long baseline interferometer) project VERA (VLBI Exploration of Radio Astrometry). We have compiled all the astrometry results from VERA, providing accurate trigonometric-annual-parallax and proper-motion measurements. In total, 99 maser sources are listed in the VERA catalog. Among them, 21 maser sources are newly reported, while the rest of the 78 sources are referred to in previously published results or those in preparation for forthcoming papers. The accuracy in the VERA astrometry is revisited and compared with that from the other VLBI astrometry projects such as BeSSeL (The Bar and Spiral Structure Legacy) Survey and GOBELINS (the Gould’s Belt Distances Survey) with the VLBA (Very Long Baseline Array). We have confirmed that most of the astrometry results are consistent with each other, and the largest error sources are due to source structure of the maser features and their rapid variation, along with the systematic calibration errors and different analysis methods. Combined with the BeSSeL results, we estimate the up-to-date fundamental Galactic parameters of $R_{0}=7.92\pm 0.16_{\rm {stat.}}\pm 0.3_{\rm {sys.}}\:$kpc and $\Omega _{\odot }=30.17\pm 0.27_{\rm {stat.}}\pm 0.3_{\rm {sys.}}\:$km$\:$s$^{-1}\:$kpc$^{-1}$, where $R_{0}$ and $\Omega _{\odot }$ are the distance from the Sun to the Galactic center and the Sun’s angular velocity of the Galactic circular rotation, respectively.

Fast Radio Bursts (FRBs), bright millisecond-duration radio transients are happening thousands of times per day. FRBs' astrophysical mechanisms are still puzzling. Bustling Universe Radio Survey Telescope for Taiwan (BURSTT) is optimized to discover and localize a large sample of bright and nearby FRBs. BURSTT will have a large field-of-view (FoV) of ∼10 4 deg 2 for monitoring the whole visible sky all the time, a 400 MHz effective bandwidth between 300-800 MHz, and the sub-arcsecond localization capability with several outrigger stations hundreds to thousands of km away. Initially, BURSTT will equip with 256 antennas, which we will test different designs and improve the system performance. Through the scalable features, BURSTT could equip with more antennas and eventually optimized designs. We expect that BURSTT initially would detect and localize ∼100 bright (≥100 Jy ms) and nearby FRBs per year to sub-arcsecond precision. Besides, the large FoV yields monitoring FRBs with high cadence, which is crucial to understanding the repetition of FRBs. Multi-

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We discovered new high-velocity components of H2O maser emission in one of the “water fountain” sources, IRAS 18286−0959, which has been monitored using the Nobeyama 45 m telescope in the FLASHING (Finest Legacy Acquisitions of SiO- and H2O-maser Ignitions by Nobeyama Generation) project since 2018 December. The maser spectra show new components with extremely high expansion velocities (>200 km s−1 projected in the line of sight), some of which are located symmetrically in the spectrum with respect to the systemic velocity. They were also mapped with KaVA (KVN and VERA Combined Array) in 2019 March. We located some of these maser components closer to the central stellar system than other high-velocity components (50–200 km s−1) that have been confirmed to be associated with the known bipolar outflow. The new components would have flashed in the fast collimated jet at a speed of over 300 km s−1 (soon) after 2011 when they had not been detected. The fastest of the new components seem to indicate rapid deceleration in these spectra; however, our present monitoring is still too sparse to unambiguously confirm it (up to 50 km s−1 yr−1) and too short to reveal their terminal expansion velocity, which will be equal to the expansion velocity that has been observed ($v$exp ∼ 120 km s−1). Future occurrences of such extreme-velocity components may provide a good opportunity to investigate possible recurrent outflow ignitions. Thus, the sculpture of the parental envelope will be traced by the dense gas that is entrained by the fast jet and exhibits spectacular distributions of the relatively stable maser features.

Fast Radio Bursts (FRBs) are bright millisecond-duration radio transients that appear about 1000 times per day, all-sky, for a fluence threshold 5 Jy ms at 600 MHz. The FRB radio-emission physics and the compact objects involved in these events are subjects of intense and active debate. To better constrain source models, the Bustling Universe Radio Survey Telescope in Taiwan (BURSTT) is optimized to discover and localize a large sample of rare, high-fluence, and nearby FRBs. This population is the most amenable to multi-messenger and multi-wavelength follow-up, which allows a deeper understanding of source mechanisms. BURSTT will provide horizon-to-horizon sky coverage with a half power field-of-view (FoV) of ∼104 deg2, a 400 MHz effective bandwidth between 300 and 800 MHz, and subarcsecond localization, which is made possible using outrigger stations that are hundreds to thousands of km from the main array. Initially, BURSTT will employ 256 antennas. After tests of various antenna designs and optimizing the system’s performance, we plan to expand to 2048 antennas. We estimate that BURSTT-256 will detect and localize ∼100 bright (≥100 Jy ms) FRBs per year. Another advantage of BURSTT’s large FoV and continuous operation will be its greatly enhanced monitoring of FRBs for repetition. The current lack of sensitive all-sky observations likely means that many repeating FRBs are currently cataloged as single-event FRBs.