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... Reinder J. Bouma Edwin van Dijk

Minor planet 9706 on August 17, 2002 in NEAT images.

Current weather in our region:

Lunar phase: (Courtesy of USNO)

Recent updates (over last 2-3 weeks)
Apr. 26, Observations of C/2017 K2, C/2019 F1, C/2020 F5, C/2020 J1, C/2020 R4, C/2020 T2, C/2021 D1, 10P and 246P. New APASS file for May.
Apr. 19, Observations of C/2017 K2, C/2019 F1, C/2019 L3, C/2019 N1, C/2019 T4, C/2020 F5, C/2020 J1, C/2020 R4, C/2020 T2, C/2020 A2,
         C/2021 A4, C/2020 A7, C/2021 D1, 10P and 246P.


SQM-L sky brightness measurements at our observing sites. Click here.


Visually observable comets
Comet
Mv
Trend
Charts
covered by APASS file
C/2017 K2 (PANSTARRS)
13-14
brightening
no
yes
C/2019 F1 (ATLAS-Africano)
14-15
near maximum
no
yes
C/2019 L3 (ATLAS)
13-14
brightening
no
yes
C/2019 N1 (ATLAS)
14-15
fading
no
yes
C/2019 T4 (ATLAS)
14
brightening
no
yes
C/2020 F5 (MASTER)
15
brightening
no
yes
C/2020 J1 (SONEAR)
13-14
near maximum
no
yes
C/2020 R4 (ATLAS)
10-11
fading
no
yes
C/2020 T2 (Palomar)
12
brightening
no
yes
C/2021 D1 (SWAN)
13
fading
no
yes
4P/Faye
14-15?
brightening
no
yes
7P/Pons-Winnecke
13-14
brightening
no
yes
10P/Tempel 2
11-12
fading
no
yes
29P/Schwassmann-Wachmann 1
-
regular outbursts, small elongation
no
no
246P/NEAT
14-15
near maximum
no
yes

NEW! April 26, a new file with comparison stars from APASS in the magnitude 10-15 range is available for the April 2021
        moonless period.


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.

A full version of this image including observing details can be viewed by clicking here.
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.







Click here for older news items.