English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

We present the astrometric VLBI observations of water masers associated withIRAS 22480+6002 (IRC+60370, hereafter I22480) with the VLBI Exploration ofRadio Astrometry (VERA). The stellar type of I22480 looks unusual as a stellarmaser source and has been debated since the 1970s. We successfully determinedthe annual parallax of a group of the water maser spots, pi=0.400+/-0.025 mas,corresponding to a distance to I22480 of D=2.50 /+0.17/-0.15 kpc. This suggeststhat the estimated bolometric luminosity of I22480 should be revised to 35 000L_sun, favoring a K-type supergiant rather than an RV Tau-type variable starpreviously suggested. Although the spectral type is unusual as a stellar masersource, the internal motions of the water maser features suggest that the watermasers are associated with the circumstellar envelope of this star. Taking intoaccount a possible stellar motion with respect to the maser feature motions, wederived a secular proper motion of I22480, (mu_alpha, mu_delta)=(-2.58+/-0.33,-1.91+/-0.17) [mas yr^-1]. The derived motion of I22480 in the Milky Way has adeviation by ~ -30 km/s in the galactic azimuthal direction from a circularmotion estimated from the galactocentric distance to I22480 and assumption of aflat Galactic rotation curve. This peculiar motion is still comparable to thosetypically seen in the water maser sources located in the Perseus spiral arm.Taking into account the peculiar motion and the proximity to the Galacticmidplane (z ~60 pc), I22480 may be a member of the Galactic thin disk.

Annual Parallax Distance to the K-type star system IRAS 22480+6002 measured with VERA