Astraea Nunatak

Astraea Nunatak (71°59′S 70°25′W / 71.983°S 70.417°W / -71.983; -70.417Coordinates: 71°59′S 70°25′W / 71.983°S 70.417°W / -71.983; -70.417) is a nunatak 6 miles (10 km) south of Staccato Peaks in southern Alexander Island. It was mapped from trimetrogon air photography taken by the Ronne Antarctic Research Expedition, 194748, and from survey by the Falkland Islands Dependencies Survey, 194850, and named by the United Kingdom Antarctic Place-Names Committee after Astraea, one of the asteroids lying between the orbits of Mars and Jupiter.

Geology

According to the British Antarctic Survey's (BAS) aeromagnetic 1975 survey of Astraea Nunatak and nearby Ceres Nunataks, this geographical feature is rich in the igneous rocks Diorite and Tonalite as presumed by the rock samples which were observed by BAS during this survey.

Aeromagnetic Survey of Astraea Nunatak and Ceres Nunataks

In December 1975, the British Antarctic Survey (BAS) (originally known as the Falkland Islands Dependencies Survey (FIDS)) embarked on an 8-week long survey observing the proposed theory of Astraea Nunatak and Ceres Nunataks having an aeromagnetic connection between one another. I. A. Crawford and R. W. Girdler embarked on the survey, along with other accompanists and personnel members, flying at a constant barometric altitude of approximately 1130 meters (3707 feet, with an east-west flightline separation of about 7.5 kilometers. Here, they proved that these geographical features were rich in geologic minerals which shared similar characteristics. Data was sampled at one-second intervals, which, at ground speed of approximately 240 kilometers per hour, equates to 15 data points for every kilometer covered. The total distance traveled on the surface was 2200 kilometers (1367 miles). The equipment used included a Geometrics G-803 proton precision magnetometer with both analogue and digital recording, a Bendix DRA-12 Doppler navigation system and Sperry C-12 gyro-magnetic compass, and a Bonzer radio altimeter.

Overall, the 2-month long survey was a successful event and contributed to the history of Alexander Island and the Antarctic Peninsula in itself. Former contributors to this survey include:

See also

References

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