| 词条 | NGC 6440 |
| 释义 |
| name = NGC 6440 | class = V | image = | caption = The globular cluster NGC 6440 | credit = HST | epoch = J2000 | constellation = Sagittarius | ra = {{RA|15|28|00.69}}[1] | dec = {{DEC|-20|21|34.5}}[1] | dist_ly = 27.7 kly (8.5 kpc)[1] | appmag_v = 10.10[1] | size_v = | mass_msol = | radius_arcminsec = 3.15' x 3.15'[2] | v_hb = | metal_fe = -0.36[3] | metal_z = | age = | notes = | names = GCl 77, 1FGL J1748.7-2020, MXB 1746-20[1] }}NGC 6440 is a globular cluster in the constellation Sagittarius and was discovered by William Herschel on 28 May 1786. It has an apparent magnitude of about 10, with a diameter of about 6 arcminutes, and its Shapley–Sawyer Concentration Class is V.[2] References1. ^1 2 3 4 {{cite simbad|title=NGC 6440|accessdate=8 January 2017}} 2. ^1 {{cite web|title=NGC 6440|url=http://spider.seds.org/spider/MWGC/n6440.html|accessdate=8 January 2016}} 3. ^{{cite web|title=A Galactic Globular Clusters Database: NGC 6440|url=http://gclusters.altervista.org/cluster_4.php?ggc=NGC+6440|accessdate=8 January 2017}} External links
3 : Globular clusters|Sagittarius (constellation)|NGC objects |
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