Welcome to Astrosite Groningen. On these pages you mainly find information, and a presentation of results, on a number of astronomical subjects that we find most interesting. Our main interests are comets and variable stars; therefore, emphasis will be on the various aspects of observing these objects (charts, observations, photographs). But we also plan to cover other topics, albeit only as an aside, such as eclipses, and atmospheric phenomena like aurora and noctilucent clouds, mainly by presenting a selection of our photographic results. We hope you enjoy this site. We always welcome comments, and suggestions for improvement. And feel free to contribute: observations, images, whatever you want to share... ![]() ![]() |
|
Current weather in our region:
![]() |
Lunar phase:
![]() (Courtesy of USNO) |
Recent updates (over last 2-3 weeks) Feb. 25, New APASS file for March. Feb. 15, Observations of C/2019 L3, C/2019 N1, C/2021 A2, C/2021 A4, 141P, 156P and 398P. Feb. 3, Observations of C/2021 A2, 141P and 156P.
SQM-L sky brightness measurements at our observing sites. Click here.
NEW! February 27, a new file with comparison stars from APASS in the magnitude 10-15 range is available for the March 2021 moonless period.
Visually observable comets Comet Mv Trend Charts covered by APASS file C/2017 K2 (PANSTARRS) 14-15 brightening no yes C/2019 F1 (ATLAS-Africano) 14-15? brightening no yes C/2019 L3 (ATLAS) 13-14 brightening no yes C/2019 N1 (ATLAS) 13 near maximum no yes C/2019 T4 (ATLAS) 14 brightening no yes C/2020 F5 (MASTER) 15 brightening no yes C/2020 J1 (SONEAR) 14-15 brightening no no C/2020 K5 (PANSTARRS) 14-15? brightening no yes C/2020 N1 (PANSTARRS) 14-15? brightening no yes C/2020 R4 (ATLAS) 11-12 brightening no yes C/2020 T2 (Palomar) 14 brightening no yes C/2021 A2 (NEOWISE) 12-13 fading no yes C/2021 A4 (NEOWISE) 13-14 fading no yes 29P/Schwassmann-Wachmann 1 - regular outbursts no yes 156P/Russell-LINEAR 14-15 fading no yes 246P/NEAT 14-15 near maximum no no 409P/LONEOS-Hill 14-15 near maximum no yes
Bright comet C/2020 F3 (NEOWISE)!
This comet, discovered on March 27 by the NEOWISE satellite as a magnitude 17 object, brightened to 7th magnitude for southern hemisphere observers before disappearing in evening twilight en route to perihelion on July 3 at slightly under 0.30 AU from the Sun. In the meantime it had become evident that this was an 'old' object, and there was good hope that northern hemisphere observers would see a naked eye comet near about magnitude 3 deep in morning twilight shortly after perihelion. So it was a pleasant surprise that C/2020 F3 actually emerged as a first magnitude object sporting a bright dust tail that rapidly grew longer and longer over the last week as the comet could be seen higher above the horizon in a darker sky. The (binned) image to the right was obtained on the early morning of July 12 by Martin Mobberley from Cockfield, Suffolk, UK and is a fair representation
of what visual observers were able to see around the same time. Over the coming weeks comet NEOWISE, now placed in the evening sky, will fade fairly rapidly after its closest approach to the Earth - the minimum distance was 0.692 AU around 23.0 July - moving south and becoming better placed for more southerly observers. |
|