Interim report – Neptune in 2015
2016 January 26
This interim report of the 2015/2016 apparition of Neptune is based on observations made by Paul G. Abel (UK), Abdul Ahad (USA), Andrew Clitherow (UK), Marc Delcroix (France), Peter Edwards (UK), Clyde Foster (South Africa), Mike Foulkes (UK), Simon Kidd (UK), Manos Kardasis (Greece), Willem Kivits (the Netherlands), Stanislas Maksymowicz (France), Damian Peach (UK), Paul Maxson (USA), Darryl Milika & Pat Nicholas (Australia) and John S. Sussenbach (the Netherlands). The planet had an angular size of 2.4 arcsec at opposition which occurred on 2015 Sept 1. The planet’s south pole was tilted to the Earth by approximately 26°.
Voyager 2 images and subsequent professional observations using the Hubble Space Telescope or large ground-based instruments have shown Neptune to have an active atmosphere. However depending upon seeing and telescope aperture, the best that most amateurs can do is to resolve the small disk as shown in Figure 1 (This figure is oriented with south upwards as are all figures in this report).
In recent apparitions both David Gray and Stanislas Maksymowicz have reported some lighter areas on the disk but the detection of disk detail has been rare. During the 2014 apparition, Anthony Wesley (Australia) was able to image a bright region on the planet in infrared. Animations derived from his individual images showed that this region moved with the rotation of the planet. This showed that amateurs can now image large storms given suitable equipment. (…continued)
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