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Observation by Alex Pratt: (618) Elfriede occults TYC 4698-00467-1

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Alex Pratt


Alex Pratt


2021 Feb 01 - 19:26


2021 Feb 02 - 10:48


618 Elfriede

  • C11 f/10 and f/3.3 focal reducer
  • Watec 910 video camera
  • IOTA-VTI GPS time inserter
  • OccuRec (recording)
  • Tangra and AOTA (reduction)

0.04 s



Target name

(618) Elfriede and TYC 4698-00467-1


(618) Elfriede occults TYC 4698-00467-1

About this image

I was almost on the centreline for this event, with ~100% probability of a successful observation, if only the weather cooperated. The 128 km diameter asteroid (618) Elfriede was predicted to occult a mag. 8.8 star in Cetus for up to 6 seconds.

I was fortunate to be under a clear sky and recorded the 5 mag. drop in brightness lasting for 6.16 s

    D  - 19 26 15.48 ± 0.02

    R  - 19 26 21.64 ± 0.02

Other observers were either clouded out or too far away from the 141 km-wide shadow track.

Shortly after this event the sky gradually clouded over, heralding the oncoming snowfall.



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