CCD Measurements of Espin s Neglected Double Stars: First in a Series

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1 Page 97 CCD Measurements of Espin s Neglected Double Stars: First in a Series Juan-Luis González Carballo Foro Extremeño de Astronomía, FEXDA Agrupación Astronómica de Sabadell, AAS Observatorio Cerro del Viento, MPC I84 Badajoz, Spain struve1@gmail.com Abstract: In this paper I present the first in a series of CCD theta/rho measurements of double stars from T. H. E. C. Espin s catalog. In this project, I focused on the neglected doubles. I report here the first 100 measures. In addition, during this campaign, I found six new double stars, either new closed components of some of Espin s systems or new common proper motion doubles of nearby pairs. Introduction A few months ago I observed on the same night several double stars with the initials ES. I was surprised by the number of them occupying a small portion of the sky, and I thought about finding information on the astronomer hiding behind those letters. Then, I remembered a lovely old photograph featuring Thomas Espin, which I had found some time ago. I had even used it for one of my blog s posts. Shortly there after, I began my little research on this great English astronomer of the late 19 th century and the first third of 20 th, as I was hooked not only by his extraordinary capacity for work, but also by the passion he felt for double stars. Accordingly, I decided to dedicate a good portion of my time as a doubles observer to track down all the Espin stars I could. I contacted Dr. Brian D. Mason, fo the U.S. Naval Observatory, who kindly sent m a complete filtered list with all the stars that appear as neglected in the WDS. Even though the task seemed daunting, I decided to steel myself to get down to work, inspired by the similar work developed my friend and colleague Edgar R. Masa Martin from Valladolid (Spain) in the case of Stein. A total of 447 stars had not been observed over the last 20 years, considering them therefore as neglected. A little planning helped me to appreciate the opportunity to develop this enterprise and I started my observations at the end of Today, after 16 observation sessions, I can state that I have seen 80% of these doubles. In this paper, I present the first series of neglected doubles of Espin: 100 pairs. The rest will appear in subsequent works. In addition, thanks to the work done, I could detect some new and uncataloged double stars, both pairs with common proper motion (CPM) in the vicinity of Espin stars, and new closed components of some systems cataloged by our dear English amateur astronomer. About Espin The Rev. Thomas Henry Compton Espinell Espin was born May 28, 1858, in Birmingham, England. He received a good education, first at home through the attentions of his father, and later at Haileybury and Imperial Service College of Hertford to complete his training at Exeter College, Oxford University, where he graduated with honours in Just one year later he was ordained a deacon and months later he

2 Page 98 was consecrated as a pastor. Between 1882 and 1885, he held the position of assistant in the parishes of West Kirby and Wolsingham; he stayed there until 1888 when he was appointed permanent pastor of the nearby church of Saint Philip and Saint James of the small town of Tow Law. He remained there until his death in 1934 at the age of 76. In Tow Law he would lead a quiet and pleasant life with full dedication to his position and, of course, hobbies. He was known to spend nights at the observatory, even in adverse weather conditions. Along with his church, he enjoyed a comfortable vicarage surrounded by gardens. Espin was a lover of an orderly life and he had a soft spot for cats, which accompanied him on his nights at the observatory (Figure 1). In addition to his work as a clergyman and astronomer, Espin was interested in many fields of science: he was a pioneer in the use of astronomical photography, spectroscopy and the use of X-rays applied to medicine (as he did to build a hospital in his homeland for the care of tuberculosis). Likewise, he developed an equal interest in botany and geology. Espin was, undoubtedly, a well-known astronomer of his time, not only for his tireless efforts in the observation, but also for the discovery of double stars. He developed a fulfilling career as a researcher, while promoting associative work among amateur astronomers of his country -an odd curiosity in a lonely person like him. The beginning of his interest in the heavens seems to have started at the early age of 14 while he was a student at Haileybury College, around A professor, F.J. Hall, aroused his curiosity in astronomy, enjoying his first telescopic observations in the small observatory at the college. Only 18 months after his baptism as astronomer, on January 11, 1878, he was elected Fellow of the Royal Astronomical Society (RAS), a fact completely unusual due to the youth of the new member, thus becoming the youngest ever elected. At that time he began to publish his observations with some frequency in smaller publications such as English Mechanics. In those astronomical formative years he established important contacts with leading astronomers: - Thomas W. Webb, whom he helped in the compilation of his book of Celestial Objects (he was in charge of the following editions of this book), and the Professor of the Savilian Chair of the University of Oxford Charles Pritchard, who served as his mentor in the working sessions at the telescope until he graduated at this University. Figure 1: Thomas Espin with one of his loving cats (Courtesy of Mrs. Pauline Russell, University of Durham). Also in those years, he began to develop the idea of creating an astronomical club in Liverpool. As a result, the Liverpool Astronomical Society was set up formally in 1881, with Espin a founding member. It wasn t the last association that he promoted, because in 1904 we find him doing the same with the Newcastle Astronomical Society; he would be its president until his death in Espin was also a founding partner of the leading amateur club in Great Britain, the British Astronomical Association, besides being either an honorary member or correspondent for other associations around the world. There is no doubt that one of the most glorious moments in his astronomical life was the discovery of a nova in the constellation of Lacerta, known as Nova Lacertae 1910 (currently DI Lac). It reached a brightness of 4.6, decreasing for 37 days to end up in its usual magnitude (between the 14th and 15th). Espin discovered it on December 30 of that year while observing double stars in that region of the sky just af-

3 Page 99 Figure 2: Th. Espin (left) and W. Milburn at the 6 meters Tow Low s Observatory (Courtesy of Mrs. Pauline Russell, University of Durham). ter the sunset and noticed that this bright star was not in their charts of Argelander. He ran from the observatory to the vicarage to get its spectroscope to try to obtain the spectrum of the new star. Half an hour later he ran again, this time to the post office to send a telegram to the Greenwich Observatory, where the discovery was reported to Harvard and where photographs were taken that night. As a reward, in 1913 he was awarded the Jackson-Gwilt Medal of the RAS. By then he had the help of a promising young man, William Milburn (MLB in WDS), whom he hired as an assistant and who would work with him until the end of his life. After that time, he focused his work almost exclusively on the cataloguing of new pairs of double stars, amounting to several thousand in his mature years. However, he still had time to discover as many as 20 variable stars and deep sky objects that are entered into the Index Catalog (IC), including emission nebulae, open clusters and even a planetary nebula. The relatively comfortable position enjoyed by Espin over his life allowed him to have a scientific and astronomical equipment that was very advanced for his time. After taking office in 1885 in the parish of Wolsingham, he achieved a stability that resulted in his most productive years of astronomical dedication. And after enjoying the various scientific instruments and telescopes, of increasingly larger diameter and sophistication, he finally built an observatory six meters (Figure 2) in diameter to host a large telescope: the giant "(438 mm) reflector. The observatory had to be moved, three years later, to Tow Law when, in 1888, Espin received his final destination in the parish of the town. However, in 1914, his aspiration to have an even bigger telescope, led him to acquire the 24" (609 mm) Calver reflector, giving the use of 17.25" to Milburn. For the rest of his life, he remained an observer until the age of 74, only two years before his death. He was devoted to the observation of double stars and had a true passion for their observation and cataloging. His list of publications on the subject is very long, especially after 1912 when he was helped by Milburn. In the dark face of the Moon, soon after crossing the northeast limb of the visible face from Earth, there is a prominent crater of 75 km in diameter, called Espin, the hunter of stars in the solitude of his small observatory of the distant Tow Law vicarage. A more extensive biography of Espin was published by us in the winter issue of 2011 of the Spanish magazine "El Observador de Estrellas Dobles (OED) and can be downloaded for free from their website (Gonzalez Carballo, 2010). The Espin s Neglected Doubles The result of such a long astronomical life is difficult to be summarized, but it s enough to say that one of his spectroscopes, designed by himself, was able to observe all the stars of the Argelander s charts below the 9th magnitude, and cataloged 3800 red stars. However, it is his contribution to the world of double stars which has attracted the attention of posterity, especially for us. Almost all of Espin s double stars, despite their variety, have a difference in brightness between the components rather striking, though, as noted by Comellas (1988), Espin used to exaggerate the real differences between them. The secondary components are almost always brighter than recorded. Their positions are quite accurate, proof of his expertise in the management of graduated circles. In his publications he cataloged 2574 new double stars, plus another 912 that Milburn added after his death, a total of In the WDS there are 3135 stars with his designation (ES), of which a total of 429 (12.3%) are considered neglected, according to the list made for us by Brian Mason. Today, a few decades after his death, he still appears in the "Top Ten" of the WDS as one of the most active observers. The distribution of the Espin s double stars in the sky is fairly concentrated in constellations that culminate between summer and autumn, which is not surprising when you consider the harsh winters of the English east coast in that latitude, and the common weather conditions in Great Britain. In fact, seven

4 Page ,6 20,8 10,2 8,4 7,4 5,3 5,6 4 3,2 3, ,7 28,6 15,5 9,1 5,5 3,5 2,5 1,9 0 AND AUR CAS CYG DRA HER LAC LYR PEG OTHER 0 <2" 2-4" 4-6" 6-8" 8-10" 10-12" 12-14" >14 Figure 3: Distribution of Espin s neglected double stars by constellations (in %). Figure 4: Rho-value s frequency histogram of the Espin s neglected double stars (in %). constellations account for 74.2% of the doubles listed by him (Lacerta, Lyra, Andromeda, Perseus, Cassiopeia, Auriga and, above all, Cygnus, which has 25% of total). The neglected doubles have an obvious similar spatial distribution (see Figure 3), most of them concentrated in the constellations mentioned above. Most of them are stars that have only one observation in the WDS, since its discovery (59.7% of cases). The rest of his neglected doubles have two measurements, in many of the cases having been observed by himself this second time. It's very strange that some Espin s neglected couples have more than two observations (10.5%). Espin s systems are almost always composed of two stars, it is rare to find triple or, even more difficult, quadruple ones. Most of the Espin s neglected stars have precise coordinates. The A components have, on average, a magnitude of The B components always seem to be much lower (12.8) although, as mentioned above, he often exaggerates the weakness of the brightness of the secondary components. It is in this high dm where the greatest difficulty to observe and measure the Espin s neglected doubles lies. Rho values clearly vary between just over 1 of separation and, in some cases, it s a striking 87 (ES2428AB). However, Espin s neglected doubles have, on average, an angular separation of 5.3 (see Figure 4). Equipment and methodology Most of the work has been developed in the usual location used by the author, situated on the roof of his residence. Called Observatorio Cerro del Viento, it is located in the same named neighborhood of a small town in western Spain (Badajoz) and it has the MPC code I84. The conditions of observation aren t, of course, ideal for astronomical practice, although the choice of suitable nights and the use of new technologies allow for astrometry of good quality. Occasionally I had a few observing sessions from a most appropriate location, a garden in the author's family home, located in a suburban neighborhood of the small village of Valencia de Alcántara (Cáceres). Because of their better seeing conditions and transparency, these sessions in a rural place were left to work with closer Espin s doubles because they require higher quality skies. The equipment used consists of a 0.2 m Celestron Schmidt-Cassegrain telescope at f/10. The telescope operates on a CGEM mount of the same manufacturer (Figure 5). I used an Atik 16HR CCD camera to obtain the images, it was on loan, courtesy of Rafael Benavides Palencia. This camera has a Sony ICX- 285AL chip, which has a pixel size of 6.45 x 6.45 microns and an image size of 1390 x 1040 pixels. For this project I always worked in primary focus at 1x1 binning mode, so I obtained a resolution of 0.70"/ pixel and a field of 16.2' x 12.1'. The resulting focal length was 1920 mm. For each system at least 40 images were taken. In most cases the exposure times were 2 seconds, enough Figure 5: Equipment of the Observatorio Cerro del Viento MPC I84. Note that the CCD shown in this image (Atik 16IC) was not the CCD used for this paper (Atik 16HR).

5 Page 101 to capture all Espin s systems components. However, in some cases, especially due to the high ΔM of some systems, I worked with lower exposures, 1 second or less, to prevent saturation them and obtain higher quality astrometry and photometry. All images were treated with the corresponding dark-frames. I used MaxIm DL (from Diffraction Limited) for imaging and CCD camera control software. These images were averaged in groups of 8 with Astroart 3.0 software performing a manual stack that allowed me to eliminate those that have poor quality due to turbulence or poor guiding; in this way, I finally obtained 5 master images with a better signal/ noise relation (SNR). These five master images can be averaged again to get even a better quality one. Thus, I have for every system a total of 6 high quality images with an excellent SNR for all the measures I made. The astrometric reduction was carried out by software developed by Herbet Raab, Astrometrica (version 4.6) using UCAC3 catalog which usually yields residual differences of less than 0.1. After obtaining the absolute astrometry of our stars in these 6 images, I proceeded to calculate theta (angle position) and rho (angular separation) with the application created by Julio Castellano, Dobles. In addition, Astrometrica also calculated the resolution per pixel and the orientation of the image, both necessary in order to perform measurements with the Reduc software, the impressive software developed by our French friend and colleague Florent Losse. I used version 4.6. This method was used with closesr pairs (generally, 2.5 or less). In these cases, Reduc turned out to be a fundamental tool. However, when possible, every system was measured using both types of software, so the data presented here are the average of both measures. Only those closer pairs have been measured exclusively with Reduc by their best reliability. In the Notes section that accompanies the Table of measurements, I have indicated the absolute astrometry of the A component star (calculated with Astrometrica) in case the WDS Catalog has an error of identification or position of some of the systems. The Measures In Table 1 I present the measures of the first 100 Espin s neglected double stars. I also included six new discoveries of systems that were found in the vicinity of some of the studied doubles or, in two cases, there are new components of some of them. The images were taken between November 3, 2010 and July 8, In Table 10 I present a selection of the most of the Espin s observed pairs. These are cuts from the images in fit format (200x200 pixels of the original). The data structure in the table (from left to right) is as follows: - Column 1: WDS catalog Identifier. They are listed in order of increasing right ascension. If the double of one line is a new discovery it will show the name "uncat"; in this cases I haven t scored any identifier in the hope that will assigned by the USNO. If it is a new component of an Espin s system we use the same identifier of the WDS. In all these cases, the exact coordinates (J2000) can be found in the "Discoveries" section. - Column 2: Name of the system. If the double of that line is a new discovery, I have maintained the traditional nomenclature of the WDS, employing the observer code that the author has in the catalog (CRB). - Columns 3 and 4: Magnitudes for each component, given in WDS catalog. In the case of new doubles it has proceeded to annotate (in cursive boldface) other one proceeding from other sources. For more details, see the section Discoveries. - Column 5: The epoch of the observation, given in fractional Besselian year. - Column 6: Position Angle (in degrees). - Column 7: Angular Separation (in arcsec). - Column 8: Number of nights. - Column 9: Notes.

6 Page 102 Table 1: Relative Astrometry of the Observed Pairs WDS Id. Discoverer WDS Mags. Epoch Theta (deg) Rho (a.s.) Nights Notes ES uncat CRB 2AC ES ES ES ES ES ES 270BC ES 458AC ES ES 2146AC ES ES ES ES ES ES ES 2562AB ES 1527AC ES uncat CRB ES ES 1231AC ES ES ES 1232AB ES 1232AC ES ES ES ES 2098BC ES 2621AH ES 1240AC , ES 1081AB Table 1 continues on next page.

7 Page 103 Table 1 (continued) : Relative Astrometry of the Observed Pairs WDS Id. Discoverer WDS Mags. Epoch Theta (deg) Rho (a.s.) Nights Notes ES ES ES ES 70BC ES ES 2661BC ES ES ES uncat CRB 4BC ~ ES NOT FOUND ES 2420AB ES ES 2021AC ES ES ES 2233BC ES 1428BC ES 2030AB ES ES ES ES 1432CD ES 1663AB ES ES 2240AC ES ES 2241AB ES 2241BC ES 2241BD ES 655BC ES 491AB ES 656AC ES 656CD ES ES ES Table 1 continues on next page.

8 Page 104 Table 1 (continued) : Relative Astrometry of the Observed Pairs WDS Id. Discoverer WDS Mags. Epoch Theta (deg) Rho (a.s.) Nights Notes ES ES ES ES 1565BC ES 84AB ES 84AC ES 84BC ES 23AC uncat CRB ES 2371CD ES 2427AB ES ES 2428AB ES ES 2118AB ES ES 85AD ES ES 799AB ES 799CD ES uncat CRB ES ES ES ES 1102BC ES 1102CD uncat CRB 7Ca,Cb ES ES ES ES ES ES ES Table 1 notes on next page.

9 Page 105 Notes 1. ES In And. Only measured in 1915 by Espin. Rho decreasing and theta increasing significantly due to the pm of A-component: 37.84/-3.65 (PPMXL). I see a new component with the same pm at See note below. 2. CRB 2AC. In And. New CPM pair, see Discoveries section. 3. ES In And. Only measured in Proper motion of A = 1.65/-1.15 (PPMXL). Rho decreasing. 4. ES In And. Only measured in Erroneous theta in Espin measure (+180 degrees). A componet has high proper motion: 27.2/-20.7 (PPMXL). Geat dm (3.40). The brigthness of B component is substantially weaker than what is noted in WDS. 5. ES In And. Only measured in 1924 by Espin. Theta decreasing. Difficult: great dm (4.3). 6. ES In Psc. Only measured in 1929 by Espin. High dm (3.89). Rho decreasing, theta increasing. Proper motion of A-component: 1.2/-6.8 (PPMXL). 7. ES In And. Only measured in Poper motion of A = 29.2/1.6 (PPMXL). Rho remains. Theta increasing. 8. ES 270BC. In And. Two measures in WDS (1924 and 1926). Theta and rho remains. Proper motion of A = -0.2/-7.2 (PPMXL). 9. ES 458AC. In And. Only measured in Theta remais. Rho decreasing. Icompatible proper motions: A = 1.8/-8.4 and C = -19.3/-15.3 (PPMXL). I see brighter component B as indicated in WDS. 10. ES In Per. Only measured in 1932 by Espin. Correct coordinates: A= and B= High dm (2.96). 11. ES 2146AC. In Per. Two measures in WDS (1925 and 1980). Rho decreasing and theta increasing. A very beautiful trio of closed stars (see image 7, table 8). The RGB composite image of Aladin (from POSSI and POSSII images) suggests that only A- component has pm (-27.4/-73.6, according to PPMXL). 12. ES 875. In Per. Only measured in 1910 by Espin. Theta and rho increasing. 13. ES In Cam. Two measures in WDS (1921 and 1978) measurement change A for B in theta value. I also see brighter B component. Rho decreasing. Proper motion of A-component is - 7.8/7.8. Beautiful and delicate couple. I see them weaker than WDS magnitudes. 14. ES In Per. Only measured by Espin in Rho increasing, theta decreasing. A-component has pm = 31.4/32.5 (UCAC3 and PPMXL). 15. ES Only measured in 1919 by Espin. Marked in WDS as Dubious double (X). I found it at this coordinates: A= and B= Rho decreasing. High dm (3.36). Small and incompatible proper motions, according to PPMXL (A=-8.6/2.8 and B=-10.8/- 8.2). 16. ES In Cam. Two measures in WDS (1922 and 1983). Theta decreasing. Proper motion of A=11.7/12.4 (PPMXL). dm= ES In Cam. Only measured in 1911 by Espin. Stable couple. Wrong position in WDS. Correct coordinates: A= (TYC ) and B= ES Two measures in WDS (1932 and 1985). My measurements are agree better with Espin annotations than with the latest. Stable couple. 19. ES 1527AC. In Aur. Only two measures in WDS (1916 and 1983). The 1983 measure confused the Espin couple with other two near stars ( ). Espin s couple remains stable. Incompatible pm (A=1.6/-7.7 and B=-11/- 7.3, according to PPMXL). AB is neglected too. 20. ES In Aur. Only measured in 1931 by Espin. Spect. A = A2. Rho increasing, theta slowly decreasing. High dm (2.73). Correct coordinates: CRB 3. In Aur. New CPM. Magnitudes from GSC2.3. See Discoveries section. 22. ES 959. In Aur. Only measured by Espin in Theta and rho slowly increasing. Great dm (2.49). High pm of A-component according to UCAC3 and PPMXL (0.7/-96.9). The RGB composite image of Aladin (from POSSI and POSSII images) suggests that only A-component has this high pm. Correct coordinates of A = (UCAC3). 23. ES 1231AC. In Aur. Only measured by Espin in Theta and rho increasing. A-component has significant pm: -35.9/-36.9 (PPMXL) and it s incompatible with B pm (10.7/3.5, according to PPMXL). 24. ES In Cam. Only measured by Espin in High dm (3.23). A-component has high pm (-12/- 66) and that explains the difference of the values in Ap and Sep that I have obtained. Rho increasing, theta decreasing. 25. ES In Aur. Rho increasing and theta slowly decreasing. Only two measures in WDS. Proper motion of A-component is 5.7/-13.1 (PPMXL). 26. ES 1232AB. In Aur. Theta and rho increasing. A- component s pm is substantially different what is noted in WDS: 49.8/-12.1 (PPMXL). AC pair is neglected too (see note #27). 27. ES 1232AC. In Aur. Rho increasing, theta decreasing. Incompatible proper motions (A=49.8/-12.1 an B=-5.5/5.4). AB pair is neglected too (see note #26).

10 Page ES In Aur. Only measured in 1918 by Espin. Rho increasing, theta decreasing. Difficult: high dm (4.62). Small pm in both components. 29. ES 287. In Aur. Only measured by Espin in Stable pair. The high pm of A-component (-.25/- 43.8, PPMXL) indicates than ES 287 must be CPM, although pm of B-component not appears in catalogues (UCAC3 or PPMXL). The RGB composition image of Aladin (POSSI and POSSII) suggested it too. 30. ES In Aur. Theta decreasing and rho increasing. Two measures in WDS (1911 and 1925). Incompatible proper motions according to PPMXL data (A=-17.6/-37.3 and B=-9.5/-2.3). High dm (2.92). 31. ES 2098BC. In Aur. Only measurement in WDS (Espin, 1924). Rho decreasing, theta increasing. Discrepant values of A-component pm in UCAC3 and PPMXL, in any case bigger than it is indicated in WDS. 32. ES 2621AH. In Aur. Only measured by Espin in High dm (4.89). Discrepant values between my measurement and what Espin measured in No significant proper motion in any component. The system appears very clearly in the images so, probably, it is an error in the Espin annotations. 33. ES 1240AC. In Lyn. A-component has high proper motion (95/-8 in WDS). That explains the substantial difference in theta and rho values since the first measurements of Espin (in 1913). Rho increasing, theta decreasing. High dm (4.27). 34. ES 1240AB. In Lyn. Not measured because A- component (with high pm, see note above) is actually just on the B-component. 35. ES 1081AB. In Lyn. Only measured by Espin in Theta and rho increasing. Small pm of both components. High dm (3.38). 36. ES 418. In Gem. Only measured in 1907 by Espin. Theta increasing. High dm (6.01). 37. ES In Lyn. Only one measurement in WDS (1916, Espin). Rho increasing, probably due to high pm of A-component (7/-49 in WDS). High dm (3.21). 38. ES 905. In Lyn. Only one measurement in WDS (1910, Espin). Theta and rho increasing. Incorrect coordinates in WDS, the real Espin double is a near couple located 1.5 at East. Coordinates of A = and B = ES 70BC. In Lyn. Two measurements made by own Espin in WDS (1901 and 1926). While rho is stable, theta has substantially increasing between the measurements of 1901 and 1926, probably due to an annotation error (248º instead of 348º). Not seen significant pm in any of the components. 40. ES In UMa. Two measurements in WDS (1913 and 1934). Rho and theta increasing due to A- component pm = 13.5/-24.9 (PPMXL). High dm (3.52). 41. ES In Dra. Only one measurement in WDS (1920, Espin). Values of theta and rho had change substantially since 1920 due to the high proper motion of A-component: 19.2/118.4 (PPMXL) See Figure 6. Figure 6: High pm of A-component of ES 1837 (DSSI/DSSII RGB Aladin) 42. ES In Dra. Theta and rho increasing due to pm of B-component as it can be seen in the RGB composition image of Aladin (see note below). 43. CRB 4BC. In Dra. New component of ES 2267 system, see Discoveries section. 44. ES In Lyr. Not found in the coordinates or near them. Marked in WDS as X Dubious Double. WDS Notes: Not found by Heintz at IDS position (Hei1985a). 45. ES In Lyr. Two measurements in WDS (1923 and 1940). Rho increasing and theta decreasing. pm of A-component = 19/-24. Difficult: dm = ES 1428BC. In Lyr. Two measurements in WDS (1897 and 1964). Theta and rho decreasing. Beautiful couple, delicate. 47. ES In Lyr. One measurement in WDS (1917, Espin). Precise coordinates for A = Proper motion of A-component = - 9.4/ Difficult: dm = ES 1432CD. In Lyr. Rho increasing, theta decreasing. Only one measurement in WDS (1915, Espin). No appreciate pm, small dm (0.49), very delicate couple. 49. ES 1663AB. In Lyr. One measurement in WDS

11 Page 107 (1917, Espin). Theta decreasing, rho increasing substantially due to pm of A-component (2.5/16.9 according to PPMXL). 50. ES In Cyg. Only measured in 1911 by Espin. Rho decreasing slowly and theta increasing. 51. ES In Cyg. Only one measurement in WDS (1929, Espin). Theta decreasing due to high proper motion of A-component (-3/-59, WDS). 52. ES 2241AB. In Cyg. Incorrect coordinates in WDS. Precise coordinates: A= and B= Insignificant proper motions. Stable pair. Components BC y BD, see in notes #53 and # ES 2241BC. In Cyg. Precise coordinates: B= and C= Delicate pair, small dm (0.81). Theta and rho decreasing slowly. 54. ES 2241BD. In Cyg. Precise coordinates: B= and D= Theta and rho decreasing. 55. ES 655BC. In Cyg. Only one measurement in WDS (1908, Espin). Stable pair. Insignificant pm. 56. ES 491AB. In Cyg. One measurement in WDS (1907, Espin). Stable pair. Incorrect coordinates in WDS; the correct for de A-component are: Incompatible proper motion. Optical pair. 57. ES 656AC. In Cyg. Only measured in 1908 by Espin. Stable pair. Small pm in both components. AB pair is HJ Incorrect coordinates in WDS (A= ). 58. ES 656CD. In Cyg. Stable couple. Only measured in 1908 by Espin. dm is bigger than what WDS indicates (1.77). 59. ES In Cyg. Two measurements in WDS (1917 and 1936). dm=0.77. pm A-component = -11/ ES 1565BC. In Cyg. Only one measurement in WDS (1916, Espin). Rho increasing, probably due to pm of A-component (-29/-29 in WDS). Small dm (0.33). Beautiful pair. 61. ES 23AC. In Cyg. One measurement in WDS (1915, Espin). Rho increasing, theta decreasing. Great dm (5.6). Proper motion A-component = - 7.9/-8.4 (PPMXL). Near I found a new quick CPM pair (see note below). 62. CRB 5. In Cyg. New CPM near ES 23AC. See Discoveries section. 63. ES 2371CD. In Cyg. Two measurements in WDS (1929 and 1988). The 1988 measurement is inconsistent with the observations of Espin and myself, especially in rho. Theta increasing. 64. ES 2427AB. In Cyg. Two measures in WDS (1930 and 1933). Great increment of theta and rho values due to high proper motion of A-component (- 124/-126 in WDS, -110/ in PPMXL). 65. ES In Cyg. Two Espin s measurements (1924 and 1929). I observe distinctly less bright the A- component. Rho increasing substantially due to high proper motion of A, according to PPMXL is - 60/-92.3 (-38/-78 in WDS). 66. ES 2428AB. In Cyg. There is a tiny star near A- component separated by 9. Stable couple. 67. ES In Dra. One measurement in WDS (1920, Espin). Theta and rho increasing due to pm of A- component (5/40, WDS). 68. ES 85AD. In Cyg. One measurement is WDS (1907, Espin). Theta and rho decreasing. WDS don t publish the magnitude of D-component. According to GSC2.3 Vmag is Proper motion of A=-2/-3 (WDS) and D=-7.8/-4.0 (PPMXL). 69. ES Two measurements in WDS (1911 and 1977). Theta decreasing slowly. Very delicate pair, dm = ES 799AB. In Cyg. Only one measurement in WDS (1909). Rho decreasing, theta increasing. Very closed and equilibrated pair, small dm (0.17). 71. ES 799CD. In Cyg. High dm (3.31). Insignificant pm. Only measured in ES In Cyg. Only one measurement in WDS (1931, Espin). Incorrect coordinates in WDS; the correct for A-component is: Rho increasing, theta decreasing. dm = 0.5. Insignificant pm. 73. CRB 6. In Cyg. New CPM pair near ES 2514, see New Discoveries section. 74. ES In Cyg. Only one measurenment in WDS (1931, Espin). Rho decreasing, theta increasing. Small dm = ES In Cyg. Only one measurement in WDS (1926, Espin). Theta decreasing slowly. Proper motion of A-component = 22/ ES In Cyg. Only one measurement in WDS (1924, Espin). Incorrect coordinates in WDS. Correct are: A= ES 1102BC. In Cyg. Two measurements in WDS (1900 and 1911). Rho increasing and theta decreasing. Small dm (0.33). I observe a faint star near C-component. See below (note #77). 78. ES 1102CD. In Cyg. Only measured in 1911 by Espin. Stable pair. dm = CRB 7Ca,Cb. In Cyg. New component of ES 1102 system, near the B star, see Discoveries section. 80. ES In Cyg. Only one measurement in WDS (1929, Espin). Marked in WDS as I (Identification uncertain). I see it in the position indicated in WDS. Theta and rho increasing due to proper motion of the components: A = 13/-17.9 and B = -71/32.9. Incompatible pm. Optical pair. See Figure ES In Cyg. One measurement in WDS (1924, Espin). Insignificant pm of A-component. Rho de-

12 Page 108 same spectral class (A = F7V/F8III, C = G4V/F9III, Table 3), although it has not been determined whether it is a giant red or a dwarf star. After consultation with Francisco M. Rica Romero through a private communication states that we can not conclude, with current data, whether it is a physical or an optical pair. This new pair will be further explored to try to get definitive results. Figure 7: DSS-POSS I, DSS-POSSII and RGB composition images of ES 2383 (Aladin). creasing slowly. 82. ES In Cyg. Only measured by Espin un Theta and rho increasing. 83. ES In And. Only measured in Rho decreasing, theta increasing. Spec. A = F0. Proper motion of A = 4.3/ ES 856. In And. Only measured in Rho slowly increasing, theta slowly decreasing. Propor motion of A-component = 20/4.2 (PPMXL). 85. ES In And. Only two measures in WDS (1923 and 1933). A-component has a substantial proper motion: -50.6/-4.2 (PPMXL). This explains the large decrease in rho and the striking increase of theta. 86. ES In And. Two measures in WDS (1922 and 1935). Rho and theta increasing. Proper motion of A = 15.8/-8.3 (PPMXL). Table 2: Proper motions of the new system CRB 2AC (PPMXL). pm AR pm Dec A C Table 3: JHK Photometry (2MASS). J H K A C Discoveries Six new double stars have been found. None of them has been published in any consulted source. Two of them are new close components of systems catalogud by Espin, whereas the other four are unpublished doubles located in the vicinity of other Espin s double stars; all four cases appear to be new common proper motion pairs. CRB 2AC New component of the system ES 1357 (in Andromeda). It is situated at the following coordinates: This is a star of magnitude V = based on photometry from the catalogs and UCAC3 and CMC14. It is placed at 54.65" and of the A component, Figure 8. It has a very similar proper motion to the A star of the system (see Table 2), and the Figure 8: CRB del Viento. 2AC obtained at the Observatorio Cerro

13 Page 109 CRB 3 A new pair with common proper motion located in Auriga, in the vicinity of the system ES 2466 (Figure 9). They have a high common proper motion (see Table 4) and a compatible spectral class (A = M2.5/K4III and B = M3V/K4III), calculated using the method developed by Francisco M. Rica Romero from JHK photometry of 2MASS (Table 5). Given the impossibility of obtaining UCAC3 photometry that allows us the extrapolation of the V magnitude, based on the Pavlov s equations (Pavlov, 2009), we took the one offered by GSC2.3, resulting the following V magnitudes: A = 15.49, B = The separation of both components is 50.81" and they are situated at of angular position. These two faint stars exceed the 15th magnitude (see Table 4) and their exact coordinates are: A = B = Table 4: Proper motions of the new system CRB 3 (PPMXL). pm AR pm Dec A B Figure 9: RGB composition image of the zone of ES 2466 and CRB 3 (Aladin). CRB 4 This is a new component of the system ES 2667 (in Draco). The B component of this Espin double is actually two close stars and with similar magnitude (Figure 10). They are located at the following coordinates: B = C = Table 5: JHK Photometry (2MASS). J H K A B Therefore, they are situated at 3.104" with a position angle of These stars do not appear as independent ones on professional catalogs. PPMXL only shows the proper motion (possibly combined) of a star in that position (122.3/44.6), but in view of the RGB composition of Aladin (DSSI and DSSII, Figure 11) it is clear that the two components move together. Probably it is a true physical double. It has not been possible to calculate the V magnitude for these stars because they don t appear as independent in the 2MASS catalog or elsewhere. However, we can obtain an approximation of the magnitude of the new component using the dm that resulted from the Reduc measurement of the system (dm=0.25) and the magnitude of the B component recorded in the WDS: = ~

14 Page 110 CRB 5 In the vicinity of the system ES 23AC I found a couple of stars that are moving rapidly in the same direction in view of the proper motions reflecting Simbad in the plates POSSI and POSSII from Aladin (see Figure 12). Given that the proper motion was so obvious I decided to dedicate some time researching the data I could obtain on the system. They are at the following coordinates: A = (2MASS J ) B = (2MASS J ) Figure 10: CCD image obtained by author with his usual equipment at the Observatorio Cerro del Viento. Unfortunately, these two stars are very faint. I could only find photometric references in GSC2.3 and CMC-14 catalogues which, however, only show the value of the A component: (V) and (r'mag), respectively. It is quite probable that both measures reflect, in fact, the brightness of the two components together. In the absence of references in the UCAC3, I have found quite impossible to estimate the their V magnitudes. Therefore, and in a preliminary way, I decided to indicate in the Table 1 (column of magnitude values) the same magnitude for both components, using the value which appears for the A Figure 11: RGB composition from Aladin with DSSI and DSSII images showing the common proper motion of the B and C components of the system. Figure 12: Aladin image showing the POSSII plate of ES 23 area and the localization of the new common proper motion pair.

15 Page 111 Table 6: Proper motions of the new system CRB 2AC (Lepine&Shara, 2005) pm AR pm Dec A B Table 7: JHK Photometry (2MASS). images covering a time span of half a century, he corroborates these motions. All these data should be taken with caution until we develop a more detailed and conclusive study of this system that, is very possibly real binary system. In this regard, with the invaluable assistance of Francisco M. Rica Romero, I will conduct a thorough study of the new system in which we will obtain detailed images of the BVRI photometry with the IAC-80 telescope of the Instituto de Astrofisica de Canarias (IAC). CRB 6 Near the system ES 2514 (in Cygnus), I found two relatively nearby stars that seemed to share a common proper motion. After consulting the PPMXL catalog, my intuition was confirmed by their having similar proper motion values (Table 8, Figure 14). They are located at the following coordinates: J H K A B A = B = They are separate, therefore, by 10.85" with a position angle of The GSC2.3 catalog shows a V magnitude for both components of and 16.30, respectively. JHK photometry has shown identical spectral classes: A = M0.5V/K4III and B = M0.5V/K4III (Table 9), and reinforcing the possibility that they may have a true physical nature. Anyway, like the previous one, it s requires a more detailed and conclusive study to determine its exact nature. Figure 13: Cuts from POSSI (left) and POSSII (right) plates where it can be seen the faint components of this common proper motion pair. component in the GSC2.3 catalog. I believe that I found the JHK photometry of both components in the 2MASS and it can be seen in Table 7. Using these data, I preliminarily calculated, following the methodology developed by Francisco M. Rica Romero, spectral classes that shows that both components are similar: A = M2.5V/K5III and B = M4V/ K4III. The data concerning proper motions are more illuminating. Fortunately, these two stars were measured in a much broader project that was developed some years ago (Lepine and Shara, 2005). In view of these data, which are those that are represented in red vectors of the Image 12 (Simbad), these two stars share a common proper motion (Table 6). However, it remains unpublished in the WDS or in the CCDM. Francisco M. Rica Romero has done an initial analysis to assess the quality of such measures, and, using Table 8: Proper motions of the new system CRB 6 (PPMXL). pm AR pm Dec A B Table 9: JHK Photometry (2MASS). J H K A B

16 Page 112 CRB 7Ca,Cb This is a new component of the system ES 1102 (in Cygnus). The component C proved to be a close couple. Their separation is almost in the limit of the resolution of the equipment I work with (Figure 15), so I contacted the well-known Madrilenian astrophotographer Miguel Angel Garcia, who operates a remote telescope of 35 cm at focal length of 2720 mm with a CCD STL1100 in OAR-SPAG observatory (Figure 17), located in the heart of Monfrague National Park (Cáceres). Responding to my call, he obtained a series of images using adaptive optics in which we could accurately measure those components and also obtain a beautiful view of the new system (Figure 16). Their separation is 1.62" at Given their closeness, the components do not appear resolved in the professional catalogs, making it quite impossible to calculate proper motions and magnitudes. The WDS indicates a magnitude = 13 for the C component. Figura 16: At the request of the author, this CCD image was obtained by Miguel Ángel García with his remotecontrolled observatory OAR-SPAG in Monfragüe National Park (Cáceres): 35 cm. telescope at 2720 mm. of focal distance. Here the Ca, Cb system is clearly resolved. Figure 15: CCD image of the system ES 1102 obtained by the author with his equipment (8 telescope at focal distance of 1920 mm.). All the components of Espin s system can be observed. The C star is also double (see Figure 16), as evidenced by its elongated shape. Figure 17: Remote Astronomical Observatory OAR-SPAG (Monfragüe) in which Miguel Ángel García (pictured) obtained the images that confirmed the presence of a faint star near the C component of ES (Continued on page 120)

17 Page 113 Table 10: A photographic atlas of selected Espin's doubles. 1: ES : ES : ES : ES 270BC 5: ES 458AC 6: ES : ES 2146AC 8: ES 875 9: ES : ES : ES : ES 1067

18 Page : ES 2562AB 14: ES : ES : ES 1231AC 17: ES : ES : ES 1232AB AC 20: ES : ES : ES : ES 2098BC 24: ES 2621AH

19 Page : ES 2562AB 14: ES : ES : ES 1231AC 17: ES : ES : ES 1232AB AC 20: ES : ES : ES : ES 2098BC 24: ES 2621AH

20 Page : 1240AC 26: ES 1081AC 27: ES : ES : ES : ES 70BC 31: ES : ES 2661BC 33: ES : ES : ES 2420AB 36: ES 2020

21 Page : ES 2021AC 38: ES : ES : ES 2233BC 41: ES 1428BC 42: ES : ES : ES : ES 1432CD 46: ES 1663AB 47: ES 2420AB 48: ES 2040AC

22 Page : ES : ES 2241AB BC BD 51: ES 655BC 52: ES 491AB 53: ES 656AC CD 54: ES : ES : ES : ES : ES 1565BC 59: 84AB AC BC 60: ES 23AC

23 Page : ES 2371CD 62: ES 2427AB 63: ES : ES 2428AB 65: ES : ES 2118AB 67: ES : ES 85AD 69: ES : ES : ES : ES 2259

24 Page : ES : ES 1102BC CD 75: ES : ES : ES : ES 2001 (Continued from page 112) Acknowledgements The author of this article would like to acknowledge the assistance provided all the time by the great Spanish specialist in double stars, my great friend and colleague, Rafael Benavides Palencia. In addition to his continuing assistance, his CCD camera has given, and continues to provide, an excellent service at the Observatorio Cerro del Viento. In the same way, I d like to thank Francisco M. Rica Romero for his advice on certain astrophysical data without which it would have been impossible to reach certain conclusions about the systems studied. Likewise, I wish to thank Ignacio Novalbos Cantador for his advice and guidance while I was studying some systems. Also to Miguel Ángel García, from Observatorio OAR-SPAG (Monfragüe, Cáceres, Spain) for his help in obtaining images of the new system CRB 6Ca,Cb. Without them I would not have been able to determine the double nature of the C component of the system Es Of course, many thanks to Florent Losse for developing a software as powerful as Reduc. Without it many of the doubles here measured could not have been published. To Dr. Brian D. Mason, from the United States Naval Observatory, for giving me the list of neglected double stars of Thomas Espin. With regard to biographical and bibliographical information about Espin, I have been fortunate to have a number of privileged contacts that have helped me to be aware of a more detailed knowledge of our subject s life. For this, I want to express my deepest gratitude to Mr. Simon Murray and Mr. David Hughes from the Newcastle Astronomical Society; to Professor F. Richard Stephenson and to Mrs. Pauline Russell, both from the University of Durham, for their graphic documents; to Mrs. Carol Harris, from the Library of that University, for their kind donation of a detailed and unpublished biography of

25 Page 121 Espin; and to Mr. Graham Espin for certain information published in some old English newspapers. Thank you very much for making easier my documentation of our beloved Thomas Espin. I hope this research, and the future ones I ll write, serves to remember in the 21 st century the hard work that a humble vicar developed in the solitude of his observatory in the moorlands of Tow Law. I would also like to acknowledge the assistance of my colleagues, members of the Department of English Language of the I.E.S. Ciudad Jardín (Badajoz), when reviewing the English version of this work. Thanks Alfonso, Jane, María, Montaña and Reme. And, of course, to Guadalupe and Lucía for their infinite patience and understanding of a husband and father with his head always in the heavens. In this research I used Aladin and VizieR from CDS in Strasbourg, as well as the professional catalogs available through them. References AA.VV., 1992, The Stargazer of Tow Law (foreword by Patrick More). Published by Tow Law Local History Group. Durham. Bonnarel, F. et al, 2000, The ALADIN interactive sky atlas. A reference tool for identification of astronomical sources, Astron. Astrophys. Suppl. Ser. Vol. 143, Number 1, Brown, A., 1974, The life and work of Revd. T. H. E. C. Espin, perpetual curate of Tow Law, with special reference to his astronomical research. Unpublished Thesis presented in the University of Durham. Castellano, J., 2006, Software Dobles. Available at: Software.html. Centre de Donées Astronomiques de Strasbourg, , Vizier Service. Available at : webviz.u-strasbg.fr/viz-bin/vizier. Centre de Donées Astronomiques de Strasbourg, , Aladin Sky Atlas. Available at : aladin.u-strasbg.fr/. Comellas, J.L., 1988, Catálgo de estrellas dobles visuales. Ed. Equipo Sirius. Madrid. González Carballo, J. L., 2011, Espin: una vida de pasión astronómica, OED 6, Lepine, S. and Shara, M. M., 2005, A catalog of northern stars with annual proper motions larger than (LSPM-NORTH catalog), Astron. J., 129, Losse F., , Reduc Software. Mailware available at: Mason, B.D. et al., The Washington Double Star Catalog (WDS) , U.S. Naval Observatory. Pavlov, H., 2009, Deriving a V magnitude from UCAC3, index.html Raab, H., , Software Astrometrica. Available at: Roeser, S. et al., 2008, PPMX Catalog of positions and proper motions, A&A, 488, 401. Zacharias, N. et al., 2010, The Third U.S. Naval Observatory CCD Astrograph Catalog (UCAC3), AJ Juan-Luis G. Carballo is professor of Geography and History. His two great astronomical passions are double and variable stars. He observes from an urban observatory located in Badajoz, Spain, and is co-editor of the Spanish journal El Observador de Estrellas Dobles (OED). He maintains the blog La Décima Esfera ( devoted to his astronomical works.