J/A+A/696/A67ivo://CDS.VizieR/J/A+A/696/A67doi:10.26093/cds/vizier/bc-nr/lghCDSShen X.J.Hou L.G.Liu H.L.Gao X.Y.2026-07-03T06:36:55Z2025-04-04T09:43:59ZCDS support team

CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France

cds-question@unistra.frmilky-way-galaxyh-ii-regionsstellar-distanceThe spiral structure of the Milky Way is not conclusive, even for the disc regions in the solar neighbourhood. In particular, the arm-like structures uncovered from the overdensity maps of evolved stars are inconsistent with the commonly adopted spiral arm models based on young objects. We aim to reexamine the arm segments traced by young objects and better understand the nearby spiral structure. We identified the exciting stars of 459 HII regions and calculated their parallax-based distances according to the Gaia DR3. Together with other HII regions with spectrophotometric or parallax-based distances in the literature, we used the largest ever sample of 572 HII regions with accurate distances to reveal the features shown in their distributions projected onto the Galactic disc. We then compared the results to the features traced by other young objects (high-mass star-forming region masers, O-type stars, and young open clusters) and evolved stars. The structures outlined by different kinds of young objects do not exhibit a significant deviation from each other. The distributions of young objects are in agreement with three arm-like features emerging in the overdensity map of evolved stars. In particular, the Local Arm outlined by young objects follows an arm-like feature delineated by evolved stars and probably spirals outwards towards the direction of l~240{deg} in the third Galactic quadrant. We conclude that the arm segments traced by young objects and evolved stars are consistent with each other, at least in the solar neighbourhood. In particular, the Local Arm delineated by young objects is reinterpreted as an arm segment with a large pitch angle of 25.2{deg}+/-2.0{deg}, whose inner edge is in good agreement with the recently discovered Radcliffe Wave.2025A&A...696A..67Shttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/696/A67CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toI/355 : Gaia DR3 Part 1. Main source (Gaia Collaboration, 2022)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/696/A67https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/696/A67http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/696/A67https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/696/A67https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/696/A67http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/696/A67GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/696/A67/table2 (HII regions with parallax distances based on Gaia DR3)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/696/A67/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/696/A67/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/696/A67/table2?GETtext/xml+votable180.050000true266.282625-28.8660.005555555555555556Cone search capability for table J/A+A/696/A67/tablea1 (Information of exciting stars)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/696/A67/tablea1?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/696/A67/tablea1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/696/A67/tablea1?GETtext/xml+votable180.050000true266.2821799927-28.86351961340.0055555555555555565/7207 9341 9504 6/1285 1287 1293 1296-1298 1310 1330 1428 1446 1544 1558 1564 1781 1790 1801 1811 1814 1838-1839 1848 1930 1956 2939 3011 3025 3028 3047 3058 3060 3067 3156 3245 3271 3286 3293 3301 3305-3310 3313 3320 3605 3630 3643 3648-3649 3746 3752 3754-3755 13041 13291 14029 14063 14253-14255 14263 14291 14293 14299 14304 14306-14309 14311 14317 14321 14353 14358-14359 14406 14409 14411 14419 14617 14622 14629 14633 14644 14646-14647 14666 14682-14683 14690 14696 14716-14717 14719 15409 15461 15473 15571 15627 15634 15642 15646 15664 15667 15677 15683-15684 15703 15759 20849 21439 21447 21458 21504 21510 21515 21517 21519 21537 21641 21643-21644 21646-21647 21657 21669 21671 21677 22022 22038 22045 22080 22115 22167 22208-22210 22216 22218 22240 22243 22246 22249 22252 22805 22854-22855 22861 23637 23641 23644-23645 23674 23717 23764 23767 23774 23795 23969 23972 23974 23976 23982 24325 24370 24475-24476 24507 24554 28808-28809 28811 28817 28819 28825 28878 28890-28892 28894 28912-28913 28916 29091-29092 29094 29103 29113 29115-29116 29118-29119 29459 29463-29464 29467 29504-29506 29512-29513 29515 29522 29532 29534-29535 30219 30243 30251 30256-30257 30259 30262 30268 30328 30592 30694 30697 30717 37244 37333-37335 37341 37362 37719 37746 37839 37841-37842 37846 37850 37852 37872 37874 37883 37886-37887 37889 37894-37897 37899-37900 37905-37907 37921 37926 37928-37929 37932 37934 38022 38024-38025 38038 39249 39251 39259 39273 39282-39283 39317 39375 39384 39418 39774 39804-39805 39889 39892 39896 39924 39930 40618-40619 41596 41654 41660 41662 41675 41677-41678 41682 41689 41696-41697 41733 41744 41754 41756 41759 41768 41812-41814 41817 41820 42159 42171 42206-42207 42212 42228 42362 42376 42379 42389 42392 42395 42398 42407 42417 42439 42441 42444-42445 42447 42456-42458 42460-42462 42498 42513 42516 43011 43015 43019-43020 43026-43028 43041https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/696/A67?format=asciidefaultJ/A+A/696/A67/table2HII regions with parallax distances based on Gaia DR3recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWISEHII region name given in Anderson et al., 2014ApJS..212....1A, Cat. J/ApJS/212/1 (GLLL.lll+BB.bbb)meta.id;meta.maincharCl[CGKQ] Classification of HII region in Anderson et al., 2014, Cat. J/ApJS/212/1 (1)meta.code.classcharRRadius of HII region given by Anderson et al., 2014, Cat. J/ApJS/212/1arcsecphys.angSize;obs.fieldintDistParallax-based distance of HII regionkpcpos.distancefloate_DistLower uncertainty of parallax-based distancekpcstat.errorfloatE_DistUpper uncertainty of parallax-based distancekpcstat.error;stat.maxfloatVLSR? LSR velocity of HII region (2)km/sphys.veloc;pos.lsrfloatnullablen_VLSR[;/]meta.notecharVLSR2? Second value of LSR velocity of HII regionkm/sphys.veloc;stat.value;pos.lsrfloatnullableLine? Observed line to measure VLSRmeta.id;spect.linecharr_Line? Reference for observed linemeta.ref;pos.frame;spect.linecharDkin? Updated kinematic distancekpcpos.distancefloatnullablee_Dkin? Lower uncertainty of kinematic distancekpcstat.errorfloatnullableE_Dkin? Upper uncertainty of kinematic distancekpcstat.error;stat.maxfloatnullableGroupClassification based on the robustness of the estimated parallax distances (3)meta.code.classcharRemarksNote for the HII region with determined parallax distances in literature (4)meta.notechar_RAPositions from Anderson et al., 2014, Cat. J/ApJS/212/1 (right ascension part)degpos.eq.ra;meta.main_DEPositions from Anderson et al., 2014, Cat. J/ApJS/212/1 (declination part)degpos.eq.dec;meta.mainJ/A+A/696/A67/tablea1Information of exciting stars_RA.icrsRight ascension (ICRS) (computed by VizieR, not part of the original data. The format may include more digits than the original data because of internal accuracy requirements in VizieR and across other CDS services)degpos.eq.raindexed_DE.icrsDeclination (ICRS) (computed by VizieR, not part of the original data. The format may include more digits than the original data because of internal accuracy requirements in VizieR and across other CDS services)degpos.eq.decindexedrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWISEHII region name given in in Anderson et al., 2014ApJS..212....1A, Cat. J/ApJS/212/1 (GLLL.lll+BB.bbb)meta.id.parentcharStarsExciting star namemeta.id;meta.maincharSpTypeSpectral type of exciting starsrc.spTypecharGLONCoordinate of Galactic longitudedegpos.galactic.lonGLATCoordinate of Galactic latitudedegpos.galactic.latRefReference for exciting star (1)meta.ref;pos.framecharGaiaDR3Gaia DR3 ID of matched sourcemeta.idPlxParallax of Gaia DR3maspos.parallaxfloate_PlxStandard error of parallaxmasstat.error;pos.parallaxfloatpmRAProper motion in right ascension directionmas/yrpos.pm;pos.eq.rafloate_pmRAStandard error of proper motion in right ascension directionmas/yrstat.error;pos.pm;pos.eq.rafloatpmDEProper motion in declination directionmas/yrpos.pm;pos.eq.decfloate_pmDEStandard error of proper motion in declination directionmas/yrstat.error;pos.pm;pos.eq.decfloatDistAdopted parallax distance (2)kpcpos.distancefloate_DistLower uncertainty of distance (3)kpcstat.errorfloatE_DistUpper uncertainty of distance (4)kpcstat.error;stat.maxfloatRemarks[rgeo ] Note on whether to use the median of the geometric distance posterior (rgeo)meta.notechar