ABSTRACT
Coral reefs are commonly associated with oligotrophic, well-illuminated waters. In 2013, a healthy coral reef was discovered in one of the least expected places within the Colombian Caribbean: at the entrance of Cartagena Bay, a highly-polluted system that receives industrial and sewage waste, as well as high sediment and freshwater loads from an outlet of the Magdalena River (the longest and most populated river basin in Colombia). Here we provide the first characterization of Varadero Reef's geomorphology and biological diversity. We also compare these characteristics with those of a nearby reference reef, Barú Reef, located in an area much less influenced by the described polluted system. Below the murky waters, we found high coral cover of 45.1% (±3.9; up to 80% in some sectors), high species diversity, including 42 species of scleractinian coral, 38 of sponge, three of lobster, and eight of sea urchin; a fish community composed of 61 species belonging to 24 families, and the typical zonation of a Caribbean fringing reef. All attributes found correspond to a reef that, according to current standards should be considered in "good condition". Current plans to dredge part of Varadero threaten the survival of this reef. There is, therefore, an urgent need to describe the location and characteristics of Varadero as a first step towards gaining acknowledgement of its existence and garnering inherent legal and environmental protections.
ABSTRACT
Analysis of CCD photometric observations of the near-Earth asteroid (399307) 1991 RJ2 made in 2014 August-September show it to be a binary system with a primary period of 3.4907 ± 0.0002 h and orbital period of 15.917 ± 0.001 h. The depth of the secondary mutual event indicates a minimum effective diameter ratio (Ds/Dp) of 0.47 ± 0.02. The lightcurve showing the orbital period and mutual events indicates a slightly elongated (a/b ~ 1.07/1.0) satellite that is tidally-locked to the orbital period.
ABSTRACT
CCD photometric observations of the near-Earth asteroid 2009 FG19 were made in 2014 September and October to supplement radar observations made at the same time. Analysis of the CCD data from September only found several possible periods, all commensurate with an Earth day. The most likely period was 8.00 ± 0.02 h with an amplitude of 0.80 ± 0.05 mag with an alternate solution of 9.61 ± 0.02 h being possible. The addition of data from October, even though the lightcurve had evolved noticeably, removed the 9.6 hour alias and confirmed the 8-hour solution. There were no obvious signs of non-principle axis rotation (NAPR; tumbling) but that cannot be formally excluded.
