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"We present speckle interferometric measurements of binary stars performed during September and October of 2009 with the 2.1 m telescope of the Observatorio Astronómico Nacional at SPM (Mexico). We report here the results of 200 measurements of 196 pairs with a primary limiting magnitude of V = 12.3. The measured angular separations range from 000.115 to 500.26. Ninety seven pairs have separations less than 100. The mean error in separation is 000.03 and 1º.5 in position angle. The usual 180º ambiguity was corrected for a majority of position angles by comparison with observations performed by other observers."

"We present speckle interferometric measurements of binary stars performed during August of 2010 with the 1.5 m telescope and during November of 2010 with the 2.1 m telescope of the Observatorio Astronómico Nacional at SPM (Mexico). We report here the results of 238 measurements of 225 pairs with a primary limiting magnitude of V = 12.2; 211 of them have separations less than 1. The mean error in separation is 0.03 and 1.5 in position angle. Some of the position angles were determined with the usual 180 ambiguity."

We present high quality radio continuum observations made with the Very Large Array (VLA) at 3.6 cm at two epochs toward the planetary nebula M2-43. The comparison of the two epochs, obtained with a time separation of 4.07 years, clearly shows the expansion of the planetary nebula with an angular rate of 0.61 +/- 0.09 mas/year.Assuming that the expansion velocity in the plane of the sky (determined from these measurements) and the expansion velocity in the line of sight (determined from optical spectroscopy available in the literature) are equal, we find a distance to the planetary nebula of 6.9 +/- 1.5 kpc. This is the largest distance for a planetary nebula measured up to now with this technique., Comment: 5 pages, 2 figures