We present new photometric data on 36 old open clusters using the 65-cm telescope at Gunma Astronomical Observatory. This dataset is a continuation of photometric data of old open clusters (Hasegawa et al 2004, PASJ, 56, 295) collected mainly in the antigalactic center region. By constructing a color-magnitude diagram, we inspected the main sequence and (if richly populated) red-clump stars to evaluate the cluster parameters, that is, the age, distance, and reddening, by applying an isochrone provided by the Padova group. Now, 49 old clusters have consistently measured parameters (36 clusters in this study and 13 from Hasegawa et al. 2004). The clusters are exclusively older than the Hyades cluster, and the age is distributed in the range 0.6-5.0Gyr. The oldest clusters include Auner 1, Biurakan 12, Berkeley 78, and NGC 2425. Our study includes clusters that are useful in further clarifying the outer disk of the Milky Way, and when inner clusters with galactocentric distances less than 12kpc are compared with outer ones, the latter tends to be less bound to the galactic plane. Nine clusters are found to be cospatial with the northern part of the recently identified stellar overdensity centered in the constellation of Canis Major.

We present new photometric data for 14 galactic open clusters taken by the 65 cm telescope at Gunma Astronomical Observatory. They were in the anti-galactic center region selected from the Catalog of Open Cluster Data (Lyngå 1987). We estimated the parameters of the clusters, i.e., age, metallicity, distance, and reddening, by fitting Padova isochrones to the color–magnitude diagram. While no clusters were dated to be as old as young globular clusters, 13 clusters out of 14 are older than 1 Gyr, ranging up to $\sim 3.6 \,\mathrm{Gyr}$. Bearing in mind that out of approximately 500 clusters dated so far, only 40 clusters are older than 1 Gyr, our sample is exclusively dominated by old clusters. Four clusters were found away from the metallicity gradient curve and age–metallicity relation so far delineated. Especially, 3 metal-rich clusters in the outer disk (Berkeley 36, Biurakan 11, and Biurakan 13) provide evidence against the picture advocated by Twarog et al. (1997, AJ, 114, 2556) that there is a break in the metallicity distribution at $r_{\mathrm{GC}} = 10 \,\mathrm{kpc}$ and that the outer disk is chemically less evolved than in the inner disk.

We report on a global CCD time-series photometric campaign to decode the pulsations of the nucleus of the planetary nebula NGC 1501. The WC4 central star is an extremely hot, hydrogen-deficient, "O VI"-type object, with some spectroscopic characteristics similar to those of the pre-white-dwarf PG 1159−035 stars. NGC 1501 shows pulsational brightness variations of a few percent with numerous individual periods ranging from 19 to 87 minutes. The pulsation amplitudes and periods are highly variable, suggesting a complex pulsation spectrum that requires a long unbroken time series to resolve. To that end, we obtained CCD photometry of the central star over a two-week period in 1991 November, using a network of observatories around the globe. We obtained nearly continuous coverage over an interval of almost one week in the middle of the run. With this data set, we have identified 10 independent pulsation periods, ranging from 5235 s down to 1154 s. The pulsation modes changed amplitude significantly

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