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globular clusters are important tracers of the chemical and dynamical evolution of the milky way . since the orbits of globular clusters may have kept their characteristics from the early times of the formation of the milky way , we may extract from their kinematics some clues for the understanding of the origin of the milky way . however so far for only some 40 globular clusters absolute proper motions exist ( dinescu et al . 1999 ) , which partly are of low quality ( e.g. dauphole et al . 1996 ) . nevertheless on the basis of a sample of 26 globular clusters dauphole et al . ( 1996 ) found an indication of a metallicity gradient among the halo clusters and a mean rotation of about + 40  km  s@xmath1  for the complete globular cluster sample . additional data especial for southern clusters were determined by dinescu et al . ( 1999 and references herein ) . the results of the hipparcos mission offer new possibilities for the determination of absolute proper motions of globular clusters and other objects of interest for galactic kinematics . since previous studies have used mainly extragalactic objects as proper motion zero points , the use of hipparcos reference stars offers a unique possibility for the determination of absolute proper motions at low galactic latitutes without suitable extragalactic background objects . geffert et al . ( 1997 ) have determined absolute proper motions of 10 globular clusters with respect to hipparcos . these were combined with data of 5 other clusters and the kinematics of this sample was studied by brosche et al . ( 1997 ) and odenkirchen et al . a complete discussion of these data together with additional proper motions was given recently in dinescu et al . ( 1999 ) . m10 is a globular cluster located very near to the direction to the galactic center ( @xmath2 , @xmath3 ) , but at a distance of only 4.3  kpc from the sun . due to its metallicity of @xmath4 = -1.52\;$]dex ( harris 1996 ) it belongs to the halo group of clusters according to zinn s ( 1985 ) classification . the preliminary kinematical data of m10 ( geffert et al . 1997 ) indicate a disk like motion , the most disk like motion found in the group of globular clusters , whose proper motions were determined using hipparcos ( odenkirchen et al . 1997 ) . however , this preliminary proper motion has the problem that only three to four hipparcos stars could be used for the reduction of the plates . this made the previous solution very uncertain . here we have included new photographic material ( from shanghai ) and recent ccd observations to get a new determination of the absolute proper motion of m10 . moreover , we use in addition to the hipparcos catalogue the act catalogue ( urban et al . the act catalogue , due to its denser coverage of the sky , allows the use of more reference stars for the determination of the absolute proper motions . lrrr plate no . & epoch & emulsion & telescope + 149 & 1902.6 & & dr hl + 406 & 1905.6 & & r sh + 262 & 1916.5 & & dr hl + 309 & 1917.5 & & dr hl + 312 & 1917.5 & & dr hl + 314 & 1917.5 & & dr hl + cl57016 & 1957.5 & 103a - o & r sh + cl57031 & 1957.6 & 103a - o & r sh + cl57033 & 1957.6 & 103a - o & r sh + 1232 & 1976.6 & iia - o / bg 25 & dr hl + 1874 & 1994.5 & iia - o / bg 25 & dr hl + 1875 & 1994.5 & iia - o / bg 25 & dr hl +   +    [ t_photmat ] table  [ t_photmat ] lists the photographic plates used in this work , while table  [ t_ccdobs ] indicates the observational data of the ccd frames . the plates were taken either with the ( @xmath5 m , @xmath6 m ) double refractor of bonn , now located at hoher list observatory , or with the ( @xmath7 m , @xmath8 m ) refractor of shanghai . the ccd frames were taken with the wwfpp camera ( reif et al . 1994 ) at the 1.23  m telescope at calar alto and with a similar camera ( holicam ) at hoher list observatory . the use of the complete material allows a nearly uniform coverage of the epoch difference of 92  years . the limiting magnitude of the plates is of the order of @xmath9mag , while the corresponding one of the ccd frames ranges from @xmath10 to 19  mag . the refractor plates of bonn were mainly scanned at the pds  2020gm of university of mnster . the plates r1874 and r1875 with lower limiting magnitude have been measured at the ascorecord of hoher list observatory . on these plates only 80 stars for each plate were measured . stars were extracted and rectangular coordinates @xmath11 and @xmath12 were determined from the pds measurements using standard procedures ( e.g. tucholke 1994 ) . the first epoch plates of the bonn refractor contained scratches and reseau lines , which led to problems for a significant number of the stars . therefore for some of these stars no rectangular coordinates could be obtained . the plates from shanghai were scanned at the pds 1010ms of the purple mountain observatory , chinese academy of sciences ( see also wang et al . 1999 ) . the determination of the rectangular coordinates @xmath11 , @xmath12 of the stars on the ccd frames was performed for the observations from hoher list by standard ccd reduction techniques ( daophot , iraf ) routines . magnitudes , @xmath11 and @xmath12 positions were determined via psf fit . the observations from calar alto were reduced earlier ( geffert et al . 1994 ) by the imex routine of the iraf program package . the astrometric reduction was performed by a central overlap algorithm . due to the small field of the ccd frames we had to use only the plates in the first step of the reduction . a catalogue of positions and proper motions of 450 stars was established in this first step . in the following steps of the reduction the ccd frames were included . while for the plates only quadratic polynomials of the rectangular coordinates had to be taken into account , third order polynomials were necessary for the reduction of the ccd frames . the third order polynomials for the reduction of the ccd frames had to be used due to the distortion of the optics of the focal reducer of the wwfpp camera ( geffert et al . from the different position and time pairs we determined for each star for a certain epoch the mean position and the proper motion using least squares technique . all stars with proper motion errors larger than 4 mas / yr were omitted . the final catalogue contains 532 positions and proper motions of stars in the region of m10 . the median of the internal errors was about @xmath13mas / yr . from a plot of the proper motions versus magnitude no magnitude equation was found in our data .    lclr telescope & epoch & filter & no . of frames + 1  m hoher list & 1996 & @xmath14 , @xmath15 & 10 + 1.23  m calar alto & 1994 & @xmath16 & 5 +    [ t_ccdobs ]    lr@ r@ r@lr@ r@ r@lrrrrrrr & & & & & & & & + & [ @xmath17 & @xmath18 & @xmath19 & ] & [ @xmath20 & @xmath21 & @xmath22 & ] & & & & & & + 1 & 16 & 54 & 34&.488 & @xmath23 & 45 & 20&.57 & 0.004 & 0.04 & @xmath24 & @xmath25 & 1.7 & 1.2 + 2 & 16 & 54 & 46&.910 & @xmath26 & 52 & 53&.73 & 0.006 & 0.02 & 3.5 & 5.8 & 3.3 & 0.6 + 3 & 16 & 54 & 47&.085 & @xmath23 & 23 & 06&.77 & 0.002 & 0.01 & @xmath27 & 4.4 & 1.1 & 0.3 + 4 & 16 & 54 & 48&.326 & @xmath23 & 13 & 34&.70 & 0.002 & 0.03 & @xmath28 & @xmath29 & 0.7 & 0.7 + @xmath30 & & & & & @xmath31 & @xmath31 & @xmath31 & @xmath31 +    we have performed two independent reductions of the m10 data with reference stars from hipparcos ( esa 1997 ) and the act catalogue ( urban et al . although the hipparcos stars proper motions are more accurate , they seemed to be of only limited usefulness for our work , since the majority of the plates contained only four hipparcos stars , while about 17 stars could be used from the act catalogue . therefore we consider both solutions as equivalent . table  [ t_cdsdat ] ( the complete table is available in electronic form ) gives the catalogue of our positions and proper motions for the complete field with respect to the act catalogue . the limiting magnitude of this catalogue is about @xmath9mag , which corresponds to the limiting magnitude of the first epoch plates . the size of the field is approximately @xmath32 centered on m10 . we chose the act solution for the catalogue in table  [ t_cdsdat ] . the proper motions may be transfered to the hipparcos system by adding @xmath33mas / yr and @xmath34mas / yr to the proper motions from table  [ t_cdsdat ] . for the determination of the membership we will also use the solution based on the act catalogue , while for the determination of the absolute proper motion of m10 we will take the mean of both solutions . ccds have been used in astrometry since several years , e.g. for the determination of parallaxes , double stars and for meridian circle observations ( see references in geffert 1998 ) . however most of these observations are based on ccd observations with fields of @xmath35 and smaller . since our study uses ccd observations of fields with a size at least 20@xmath3620  it seems necessary to evaluate the accuracy , which may be obtained with such telescope detector combinations . while the ccd frames of calar alto were already tested in an earlier study ( geffert et al . 1994 ) , we will concentrate here on the hoher list observations .    in a first step we have compared positions of stars from pairs of ccd frames . the positions of one frame were transformed by an affine transformation to a second frame and the rms of the differences were calculated for each coordinate . under the assumption that both frames contribute with equal weight to the differences , we have calculated from the rms the mean uncertainty of one position on one frame . these are given in table  [ t_ccdacc ] for several ccd pairs with nearly identical limiting magnitudes . in this comparison we included all stars which were detected on the ccd frames . lrrrr frames & & & lim . mag . & of stars + & [ mas ] & [ mas ] & & + 4236/4237 & 62 & 64 & 16.5 & 1373 + 4238/4239 & 120 & 120 & 18.5 & 3378 + 4240/4241 & 63 & 67 & 16.2 & 1081 + 4242/4243 & 100 & 80 & 17.0 & 1980 +    [ t_ccdacc ]    in a second test we consider only the stars which contribute to the final catalogue of our investigation . these are stars at the brighter end of the magnitude distribution . reducing the plates with one catalogue ( act or hipparcos ) leads to positions of the stars of each plate / ccd frame in a common system . the position and proper motion of each star in our final solution described in sect . 2 are determined by a fit to the positions and epochs of the different plates / ccd frames for each star . the mean position and proper motion of each star is then used to update the positions of each star for the epoch of the individual plates / ccd frames . for each plate the mean and rms of the positional differences from the initial positions are determined . the rms will give an indication of the accuracy of each individual plate / ccd frame . table  [ t_posdiff ] summarizes for the hoher list frames the mean and standard deviations for each frame . lrrrrr ccd frame & & & & & colour + & [ mas ] & [ mas ] & [ mas ] & [ mas ] & + 4236 & @xmath37 & 70 & @xmath38 & 90 & @xmath15 + 4237 & @xmath39 & 70 & @xmath40 & 70 & @xmath15 + 4238 & @xmath41 & 80 & @xmath42 & 90 & @xmath15 + 4239 & @xmath39 & 100 & @xmath43 & 50 & @xmath15 + 4240 & @xmath41 & 80 & @xmath42 & 50 & @xmath14 + 4241 & @xmath44 & 40 & @xmath45 & 50 & @xmath14 + 4242 & @xmath46 & 90 & @xmath47 & 50 & @xmath14 + 4243 & @xmath48 & 40 & @xmath39 & 90 & @xmath14 +    [ t_posdiff ]    table  [ t_posdiff ] shows a slight difference in the @xmath15 and @xmath14 frames of the order of a few mas . nevertheless the systematic deviations between the @xmath15 and @xmath14 frames are small . the positional accuracy of each star is of the order of one tenth of a pixel . this value is a little bit larger with respect to other studies ( e.g. geffert 1998 ) . the reason may be the crowding in the region of m10 . in general , the accuracy of one single frame is of the order of the accuracy of one refractor plate , which justfies the use of ccd frames for the second epoch observation . figure  [ f_vppdia ] gives the vector - point - plot diagram of all our proper motions indicating the concentration of the cluster stars . for the separation of cluster and field stars we have concentrated our investigation on stars up to the limiting radius of 14@xmath49 ( webbink 1988 ) around the cluster centre . 284 stars remained in the data sample . for these stars a bivariate gaussian fitting to the proper motions was performed using the method of sanders ( 1971 ) . table  [ t_fitpar ] gives the result of the analysis . the cluster standard deviations are larger than the internal errors of the proper motion . this difference is clearly not an indication of a possible detection of internal motions of stars in the cluster . more likely these differences are caused by crowding effects and undetected systematic errors of the different telescopes used in this investigation . m10 is a globular cluster with three slow variable stars ( clement et al . 1985 ) and several uv bright stars ( zinn et al . 1972 ; harris et al . our sample contains only the variable stars v2 and v3 ( see references in clement et al . the other special stars are located in crowded regions , below the limiting magnitude , or exhibit too large proper motion errors . both variable stars v2 , v3 have according to our investigation a membership probability of 97% . this confirms the earlier suggestion ( clement et al . 1985 ) that these stars are of w - virginis type , although v3 has a very unusual period of 7.8  days . lrlr parameter & value & parameter & value + @xmath50 & 193 & @xmath51 & 88 + @xmath52 & @xmath53 & @xmath54 & @xmath55 + @xmath56 & @xmath57 & @xmath58 & @xmath59 + @xmath60 & 1.8 & @xmath61 & 7.0 + @xmath62 & 2.0 & @xmath63 & 7.1 +    [ t_fitpar ] the first absolute proper motion of m10 based on the hipparcos system was given in geffert et al . ( 1997 ) , which was later used in odenkirchen et al . ( 1997 ) and dinescu et al . . however , as mentioned in odenkirchen et al . ( 1997 ) , the result of m10 was only preliminary due to the small number of hipparcos stars used for the reduction of the plates . the use of additional plates from shanghai has led to a significant lower proper motion in declination . however , even for this sample of plates the solution is only moderately stable : omitting one reference star leads to an absolute proper motion of m10 , which differs from the original solution by about more than the mean uncertainties of the absolute proper motions . fortunately , this is not the case for the denser act catalogue . in summary , the use of the act catalogue resulted in a more stable solution , while the use of hipparcos stars provided the more direct link to an extragalactic reference frame . the catalogues based on the act catalogue ( urban et al . 1998 ) and on the hipparcos catalogue ( esa 1997 ) contributed therefore with equal weight to the final absolute proper motion of the globular cluster m10 . we obtained a mean absolute proper motion of @xmath64mas / yr and @xmath65mas / yr . together with the distance from the sun of 4.3  kpc and a radial velocity of @xmath66  km  s@xmath1  ( harris 1996 ) we have calculated the velocity components in a system of galactic standard at rest ( @xmath67,@xmath14,@xmath68 ) , peri and apogalactic distances @xmath69 , @xmath70 , eccentricity @xmath71 and the @xmath0-component of the angular momentum of the orbit using a simple logarithmic galactic mass model ( see e.g. dauphole et al . these data are shown in table  [ t_m10dat ] . figure  [ f_m10orb ] gives the orbit of m10 integrated over 10  gyr backwards according to the method of allen & santilln ( 1991 ) using the programme of odenkirchen et al . ( 1997 ) . lrrrrrrr object & & & & & & & + & & & & & & & + m10 & @xmath72 & @xmath73 & @xmath74 & @xmath75 & @xmath76 & @xmath77 & @xmath78 +    [ t_m10dat ]    = 6.0 cm our results demonstrate the importance of the new astrometric catalogues ( hipparcos , act ) for the determination of absolute proper motions of objects located in the galactic plane . for these objects no extragalactic link of the proper motion system is available due to the absense of suitable objects . we show that the differences between the solutions based on the act catalogue and the corresponding one based on the hipparcos catalogue are small . although this result has to be checked using data of other fields , it would offer a range of applications for the act catalogue because of its larger number of stars . moreover , even reaching only moderate accuracy on the wide field ccd frames with respect to small field ccd observations , our results indicate that these observations may supersede the photographic plates in near future . the new data of m10 show an eccentricity of the orbit of 0.41 , which would place the cluster now in the range of eccentricities from 0.4 to 0.8 found for the majority of the globular clusters ( odenkirchen et al . the rotational velocity changed to @xmath79  km  s@xmath1  with respect to the @xmath80  km  s@xmath1  found in odenkirchen et al . according to its moderate eccentricity and rotational velocity , m10 belongs rather to the halo class of objects . this is in line with its metallicity . however , the @xmath0-distance from the galactic plane does not exceed 3  kpc , which would be more characteristic for a thick disk object .    as noted already in dinescu et al . ( 1999 ) recent age determinations ( hurley et al . 1989 ; richer et al . 1996 ; chaboyer et al . 1996 ; buonano et al . 1998 ) agree that m10 is an old halo cluster . together with ngc  6626 , ngc  6752 ( dinescu et al . 1999 ) and m71 , which has according to geffert & maintz ( 2000 ) a much higher age , m10 establishes a group of high age globular clusters with orbits of a disk or thick disk character . this result would imply that at the time when the oldest globular clusters were born , the milky way had already a gas distribution with a disk component , where the gas enabled the formation of clusters . on the other hand the recent age determination by rosenberg et al . ( 1999 ) places m10 in the middle of the age distribution of globular clusters . piotto & zoccali ( 1999 ) have found an unusual steep luminosity function of m10 in comparison with other clusters . our data indicate that this luminosity function was generated more likely by internal dynamics of the cluster than by the motion in the galaxy . if the luminosity function would be affected by the crossing of the cluster through the galactic plane , one would rather expect a more flat luminosity function for m10 due to the evaporation of faint stars as it was found recently for the globular cluster ngc  6712 ( de marchi et al . 1999 ) . we are indebted to h .- j . tucholke ( bonn ) for measuring some of the refractor plates . it is a pleasure to thank k.s . de  boer ( bonn ) for helpful discussions . this research has made use of the simbad database ( see wenger et al . 2000 ) , operated at cds , strasbourg , france . geffert m. , 1998 , ccd astrometry . in : p. brosche et al . ( eds ) ` the message of the angles - astrometry from 1798 to 1998 ' , proc . of the spring meeting of the astronomische gesellschaft , verlag harri deutsch , thun und frankfurt am main , p.  181 , chen l. , wu z.y . , gupta a.c . , geffert m. , 1999 , a&as 142 , 373 webbink r.f . , 1988 , kinematics of the galactic globular cluster system . in : grindlay j.e . , davis philip a.g . proc iau symp . 126 , the harlow - shapley symposium on globular cluster systems in galaxies , iau symp 126 , reidel , dordrecht , p.  49
we present the first proper motion study of m10 ( ngc  6254 ) . 
 absolute proper motions of about 532 stars in the field of the globular cluster m10 were determined with respect to hipparcos and act reference stars . 
 in addition to photographic plates of bonn and shanghai also wide field ccd observations as second epoch plates were used . 
 the wide field ccd observations show an accuracy comparable to that of the photographic plates . a good coincidence of the solutions based on reference stars from hipparcos and from act was found . 
 our final proper motions allow a sufficient separation of cluster and field stars . 
 two population  ii cepheids were confirmed to be members of m10 . 
 the absolute proper motion of m10 was determined and combined with its distance from the sun and its radial velocity . 
 the space motion and metallicity of m10 indicates the characteristics of a halo object with an orbit reaching to a maximal @xmath0-distance of less than 3  kpc .