Delta and Dawn

Delta and Dawn, also known as the Delta whales, were two humpback whales, a mother and her calf, which entered San Francisco Bay in early May 2007. They swam up the Sacramento River approximately 90 nautical miles (170 km) upstream from the Golden Gate, about 20 miles (32 km) further inland than Humphrey the Whale had gone two decades earlier. Per the Endangered Species Act, California state officials were required to rescue the animals. Their journey was thought to be longest freshwater incursion by humpback whales.

Efforts to save the whales

Staff from the Marine Mammal Center, researchers, Coast Guard personnel, and volunteers tried several methods to coax the Delta and Dawn back downriver. The Marine Mammal Center was appointed by the California Office of Emergency Services as the lead rescue agency. Officials played recordings of the sounds of other humpback whales feeding and socializing to lure them, and banged on submerged metal pipes and sprayed high-powered blasts of water to repel them, but it is not clear whether any of these were particularly effective. There was heightened concern for the whales' well-being this time, because both of them had sizable gash wounds, most likely made from boat keel or propeller strikes. Veterinarians from the Marine Mammal Center and WHOI administered antibiotics to the whales to help heal these deep open wounds, and they took samples of skin lesions incurred during the whales' extended time away from seawater to analyze them for possible freshwater bacterial infection. This was the first time antibiotics had been administered to free swimming whales in the wild.

Delta Andromedae

Delta Andromedae (δ And, δ Andromedae) is a multiple star system in the northern constellation of Andromeda. Based upon parallax measurements, is located at a distance of approximately 105.5 light-years (32.3 parsecs) from the Earth. Apart from its Bayer designation, it was also given the title Delta by Elijah H. Burritt in his star atlas.

In Chinese, 奎宿 (Kuí Sù), meaning Legs (asterism), refers to an asterism consisting of δ Andromedae, η Andromedae, 65 Piscium, ζ Andromedae, ι Piscium, ε Andromedae, π Andromedae, ν Andromedae, μ Andromedae, β Andromedae, σ Piscium, τ Piscium, 91 Piscium, υ Piscium, φ Piscium, χ Piscium and ψ¹ Piscium. Consequently, δ Andromedae itself is known as 奎宿五 (Kuí Su wǔ, English: the Fifth Star of Legs.)

This is a long-period spectroscopic binary with an orbital period of approximately 15,000 days (41 years) and an overall apparent visual magnitude of approximately 3.28. The primary of the spectroscopic binary has a stellar classification of K3 III, indicating that it is a giant star. It most likely evolved from a F-type main sequence star after consuming the hydrogen at its core. The secondary is believed to be relatively faint, as it has not been observed interferometrically. The star has two optical companions, the closest of which may be an orbiting red dwarf of class M3 with a separation of at least 900 astronomical units.