()Kagaya3

VERA v.s. VLBA

S269 (Honma et al. 2007, with VERA)IRAS 19134+2131 (Imai et al. 2007, with VLBA)10as-level astrometrycomes true!

kpc H2O maser sources (VLBA, VERA)UX Cyg: D= 1.85+0.25-0.19 kpc (Kurayama et al. 2002)W3(OH): D= 2.040.07 kpc (Hachisuka et al. 2006)S269: D= 5.28+0.24-0.22 kpc (Honma et al. 2007, PASJ in press) IRAS 19134+2131: D= 8.0+0.9-0.7 kpc (Imai et al. 2007)S Per: D= 2.510.09 kpc (Asaki et al. 2007)IRAS 00420+5530: D= 2.170.05 kpc (Moellenbrock et al. 2007)

Orion KL: D= 43719 pc (Hirota et al. 2007, PASJ in press) S Crt: D= 433+40-36 pc (Nakagawa et al. 2007) Oph East: D = 178+18-37 pc (Imai et al. 2007, submitted)NGC 1333 SVS13: D= 24410 pc (Hirota et al. 2007)

H2O v.s. CH3OH (12 GHz) (, OH)CH3OH (12 GHz) maser sourcesW3(OH): D= 1.950.04 kpc (Xu et al. 2006)IRAS 19410+2336(G59.7+0.1): D= 2.20.2 kpc (Xu et al. 2007)

M. Reid (in IAUS242)Kinematic distancesare sometimes wrong!

S Crt H2O maser(Nakagawa et al. 2007)

P-LVERA: ~30 Mira H2O masers 100 Miras ?m ~0.1 mag >>> D/D~0.05

1m ~500 Miras (~250 identified) >>> 10,000 Miras (with KAG, OAO, IRFS/SIRIUS)?

SiO/H2O (v~10 km/s)LMCMW (based on HIPPARCOS)

Water fountain = stellar jet traced by H2O maser emission11 >>> ~100SPITZER/GLIMPSE Image (Deguchi et al. 2007)W43A (Imai & Diamond 2007)

Astrometry with the VLBAGalacticrotationIRAS 19134+2131 (Imai, Sahai, & Morris 2007)

Annual parallax and Galactic rotation

Location and motion in the Galaxy Annual parallax distance: D = 8.0+0.9-0.7 kpcLocation: (R, , z)=(7.4+0.4-0.3 kpc, 625 deg, 650+70-60 pc)3D velocity (VR, V, Vz) =(3+53-46, 125+20-28, 8+48-39 )[km/s]Kagaya7.5 kpc

Location and velocity in the Galaxy scale height: =100 pc >>> (Manchado 2004).

(Blackman et al. 2001; S. Miyaji in private communication)Travel time from the Galactic plane 2.4 x 107 years M*< 8.6 M

Run away from the Galactic planeNGC 281 West(Sato et al. 2007)

z~320 pcV~30 km/s

Expansion of superbubbleChevalier (1974)E0=5.3x1043n01.12vsh1.4Rsh3.12 ~3x1052 ergRsh[pc]=141[t/106yr]0.32 >>> t=12--14MyrHI map(-65 km/s < VLSR < -25 km/s) (Hartmann & Burton 1997)NGC 281 WestHD5005

YSO+Annual parallax distanceD = 178+18-37 pcIRAS 16293-2422 in Oph EastImai et al. (2007)

YSOVLA17(Chandler et al. 2005)A1: (-1.9, -27.8)[mas/yr] A2: (-7.5,-16.1)[mas/yr] 1mas/yr >> 0.76 km/s

=H2O: (-20.6,32.4)[mas/yr]IRAS 16293-2422 in Oph East

=H2O masers on an infalling-rotating disk(Imai, Iwata & Miyoshi 1999)H2O masers along a bipoler outflow(Imai et al. 2007)Consistent configurations!

: Astrometry & Astrophysics Mira P-LMW102 quasars

: (c.f. SiO IRAS : >>> SPITZER/AKARI SiO/H2O masers of RSG in young clusters(Nakashima & Deguchi 2006)

VERA (20075~30 ~20VLBI 243 >>> ~2mm23(~10as)~100 >>> Dynamic scheduling H2O/SiO

Further more, an annual parallax is also detected. These plots show a mean of three water maser feature motions. Then we can estimate the location and motion of this IRAS source in the Galaxy. This source is located at six hundred fifty parsecs away from the Galactic plane and more slowly rotating around the Galactic center. This value (Vx) still has big uncertainty, but the source seems to be moving away from the Galactic plane. These facts suggest that this IRAS source is not so massive. Assuming that this water fountain star was born in the Galactic plane and moving to the present position with roughly constant velocity, we can roughly estimate a lower limit of a travel time to be shorter than ten to the eighth years. This time scale corresponds to this stars age and a corresponding mass is smaller than five solar masses. Stellar mass is an important information for revealing the jet driving mechanism. Because bipolar planetary nebulae are located relatively close to the Galactic plane, their progenitors may be higher mass stars. On the other hand, theoretical works support that even a single AGB star can create a highly collimated jet. In that case, the stellar mass should be relatively massive. Note that the recent theoretical model predict the creation of an equatorial flow at the same time. Anyway, our result suggests that the progenitors of water fountains and bipolar planetary nebulae may be intermediate mass stars.