The following summarises attempts to determine magnitude and colour transform coefficients for photometric projects (using the “UBVRI” colour system) undertaken at D21.
The first attempts use Landolt equatorial fields near transit, which have since been found to contain some errors in published values, or more accurately – variations in on-line sources of the Landolt catalogues.
Seven RR Lyrae variable stars were imaged over 4 nights spanning 12 June to 19 June. Targets were chosen with ‘all night’ viewing potential, to maximise data collection over a single night.
The following analysis investigates the accuracy of magnitude measurements using MaxIM DL’s information tool in aperture mode, by plotting instrument magnitude against published magnitude for a Landolt field.
Non photometric catalogues are notoriously unreliable, but are increasingly used by novices amateur astronomers using commercial software such as TheSky and MaxIM DL.
The following basic magnitude ‘measurement’ test shows results using MaxIM DL’s photometry tool, unfiltered images of a random field of stars, and UCAC3.
The Running Chicken – a rich emission nebula illuminated by a cluster of massive stars. It contains Thackery’s Globules (see inset) – dark clouds of dark cosmic dust often associated with star forming regions.
Image acquired at D21 on May 14, 2013.
(click on images for larger versions)
Testing the linearity of the KAF-16803 sensor (the anti-blooming version of Kodak’s KAF-16801) seems to reveal a workable photometric range of up to 50% of the sensor’s full well capacity and a ‘comfortable’ upper limit of 40,000 ADU.
A rare and beautiful apparition. Jupiter and the moon dance over the course of an hour or so in the early evening of February 18th.
(click image for large version)
(Click image for large version)
2012 TV discovered by our friends at Tenagra was imaged by the new Ritchey-Chrétien at D21. With an estimated diameter of between 20m and 40m, this fast moving NEO brightened and sped up as it headed south, coming within the orbit of our moon.
Click here to open a video of the NEO, produced using exposures of 5 seconds, taken at intervals of 15 seconds over the course of 32 images.
7th October 2012, 13:34:03UT. A 10 second exposure. Field is approximtely 30 arc minutes.
(click on image to enlarge)
The new 14″ Ritchey-Chrétien.
A last image of Sol, resplendent with sun spots, before the great Venus transit of 2012. This image was acquired with a Canon 5D at the prime focus of a 132mm refractor using Baader solar film on May 21st, 2012
(click image to enlarge)
NGC 5078 and NGC 5101 appear in this two field mosaic. The combined field is just under 40 arc minutes wide by 20 arc minutes high.
(click on image for full size version)
NGC 253 imaged under light polluted and hazy (smoke filled) skies on October 31st.
A combination of 2 hours of luminance, combined with 30 minutes each of RGB. The image was hurriedly processed in PixInsight, and tweaked in Photoshop.
(click on image for full size version)
These two famous objects were targeted recently in order to test some of the features of the PixInsight image processing software.
47 Tuc (NGC 104) is comprised of several BVR sub frames using 60s exposures. Omega Centauri (NGC 5139) has been captured using photographic RGB filters.
The data for 47 Tuc was acquired at D22, and Omega Centauri here at D21.
(click on images to enlarge)
This LRGB composite of the Sombrero galaxy (M 104) was created using the PixInsight image processing workflow from data captured under the light polluted skies of D21.
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Despite intermittent clouds and rain, some images of the June 16 Lunar Eclipse were successfully obtained at D21, using a 132mm refractor and a DSLR.
The Minor Planet Center’s reports for August reveal a record breaking month for D21, Shenton Park.
From July 20 to August 8, we made 348 observations of 78 objects (previous best was 266 back in August 2007). Among the many submitted NEO recovery observations, D21 features on a number of special MPECs, including 2 faint NEOs recoveries (2002 AC9, 2002 NE71), 9 NEO confirmations, and 1 new main belt asteroid (2010 OE100).
Thanks as always must go my collaborator Dr Paulo Holvorcem, and his excellent pipeline.
Three quick confirmations before the onset of bad weather. The MPECs for each can be found at 2010PM10, 2010PQ10, and 2010PR10.
With the published observations of 2010 NR1, Shenton Park Observatory hits its 1000th published Near Earth Object observation. Together with this milestone, D21 also confirmed 2010 PM10 at magnitude 19.7. The MPEC can be found here, and D21’s full listing of 1000 NEO observations can be found here at NEODyS.
Despite cloud interruptions, automation at D21 allowed the recovery of 7 NEOCP objects, 4 of which appear on special MPECs. The night began with confirmation attempts on 5 new LINEAR targets. D21 achieved two immediate recoveries, reducing the target uncertainties to zero. Automated resumption after clouds allowed the recovery of the remaining LINEAR targets, including 2010 PL9 with a published magnitude of 19.7, and two new NEOs from our cousins at E12. The 4 confirmations that achieved MPECs are 2010 PH9, 2010PJ9, 2010PK9 and 2010PL9.
Thanks as always to Paulo’s uncanny targetting skills, and excellent pipeline.
Another busy two nights at D21 following up LINEAR and WISE targets sees us join a number of other observatories in confirming several new near Earth objects, including two which appear in special MPECS – 2010 PJ and 2010 PO2.
With an uncertainty line of some 16 degrees long, Paulo Holvorcem scheduled a of mosaic of 35 overlapping fields at Shenton Park Observatory. The NEO was finally found almost 4 degrees from its nominal position on night two of the search. A third night of clear skies at Shenton Park netted this important recovery thanks to Paulo’s excellent pipeline. The MPEC can be found here.
D21 Shenton Park finds its third main belt asteroid during routine recovery work on July 20. The asteroid’s orbit appears more eccentric and have lower perihelion than
typical main belters. At a magnitude close to 19, the object appears clearly in this compilation of 300s images … Continue reading
D21 Shenton Park recovers 2002 AC9 under the waxing first quarter moon. Pre-recovered in images taken on July 19, 2002 AC9 was found again on July 20 approximately 1 degree from its nominal position. A 15 field mosaic was initially used to track down the magnitude 18.5 minor planet, in which an additional 11 faint known main belt asteroids were also detected by Paulo’s excellent pipeline. The MPEC can be found here.
Additional images of 2002 BF25 taken by Paulo Holvorcem at D21 on July 19 have reduced the uncertainty to < 1″ in time for scheduled radar observations at Arecibo. Imaged in the morning sky, 2002 BF25 is now moving at 9.5 degrees per day as it heads towards solar conjunction.
Under freezing temperatures, D21 recovers 2002 BF25 over two clear winter nights. Observed last in March 2002, the recovery has reduced the uncertainty of 2002 BF25 considerably. This is important, as the object will become an Arecibo radar target during July 22nd – 24th. The MPEC can be found here. Thanks to Paulo Holvorcem.
Image details: 60 minute each of HaLRGB over 2 nights (click to enlarge).
Image details: 30 minutes through Ha (click to enlarge).
Image details: 120 x 60s images (click to enlarge).
Image details: 60 minutes each of LRGB obtained over 2 nights (click to enlarge).
Shenton Park Observatory joins a number of others in the confirmation of two new Near Earth Objects – 2010 JF and 2010 JG – thanks to some excellent seeing, and Paulo Holvorcem’s hard work. The two MPECS can be found here (2010JF) and here (2010JG).
An intervening full moon, and a quiet period for southern hemisphere observers allowed D21 to assist in the recovery of 2008 JP as it slid past our sister station’s southern horizon. The MPEC can be found here.
A near encounter with the south celestial pole, 2007 XB10 is finally recovered by D21 under some challenging weather conditions.
Shenton Park Observatory (D21) continues its record breaking faint target work with the recovery of 2008 VK14.