Wonderful report there Ron, thank you so much for sharing, and I apologise that it took so long to respond to it.
I went looking around for some pretty pics of those two objects, and I came across this beautiful pic..
Here is a pic from our deep sky forum of the two objects in the same fov (taken by Steve35)
And I also came across some interesting reading here from the Cornell University Library, regarding NGC 6440. NGC 6441 mentioned in the article below is one of my favourite globs.
Quote:
Eight New Millisecond Pulsars in NGC 6440 and NGC 6441
Paulo C. C. Freire, Scott M. Ransom, Steve Begin, Ingrid H. Stairs, Jason W. T. Hessels, Lucille H. Frey, Fernando Camilo
(Submitted on 6 Nov 2007 (v1), last revised 9 Nov 2007 (this version, v2)) Motivated by the recent discovery of 30 new millisecond pulsars in Terzan 5, made using the Green Bank Telescope's S-band receiver and the Pulsar Spigot spectrometer, we have set out to use the same observing system in a systematic search for pulsars in other globular clusters. Here we report on the discovery of five new pulsars in NGC 6440 and three in NGC 6441; each cluster previously had one known pulsar. Using the most recent distance estimates to these clusters, we conclude that there are as many potentially observable pulsars in NGC 6440 and NGC 6441 as in Terzan 5. We present timing solutions for all of the pulsars in these globular clusters. Four of the new discoveries are in binary systems; one of them, PSR J1748-2021B (NGC 6440B), has a wide (P_b = 20.5 d) and eccentric (e = 0.57) orbit. This allowed a measurement of its rate of advance of periastron: 0.00391(18) degrees per year. If due to the effects of general relativity, the total mass of this binary system is 2.92 +/- 0.20 solar masses (1 sigma), implying a median pulsar mass of 2.74 +/- 0.21 solar masses. There is a 1 % probability that the inclination is low enough that pulsar mass is below 2 solar masses, and 0.10 % probability that it is between 1.20 and 1.44 solar masses. If confirmed, this anomalously large mass would strongly constrain the equation of state for dense matter. The other highly eccentric binary, PSR J1750-37A, has e = 0.71, and periastron advance of 0.0055(3) degrees per year, implying a total system mass of 1.97 +/-0.15 solar masses and, along with the mass function, maximum and median pulsar masses of 1.65 and 1.26 solar masses respectively.
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