Transient Plotter...

 Astronomical transients have always been of special interest - the radio astronomy Vela pulsar observations searching for 'glitches' were motivated by this. Now activities have migrated over to optical astronomy and that interest in transients remain.

A subscription (free) to email alerts from the Transient Name Server (TNS) was made and alerts come in this format in an email...

The following new transient/s were reported on during the last day:

2024aazu RA=18:55:37.530, DEC=+01:30:48.46, Discovery date=2024-11-05 01:22:04.800, Discovery mag=14.42 ABMag, Filter: G - Gaia, Reporter: S.T. Hodgkin, E. Breedt, A. Delgado, D.L. Harrison, M. van Leeuwen, G. Rixon, T. Wevers, A. Yoldas ..., Reporting group: GaiaAlerts, Data source group: GaiaAlerts

2024aazw RA=20:15:22.890, DEC=+36:30:45.47, Discovery date=2024-11-04 09:51:50.400, Discovery mag=14.44 ABMag, Filter: G - Gaia, Reporter: S.T. Hodgkin, E. Breedt, A. Delgado, D.L. Harrison, M. van Leeuwen, G. Rixon, T. Wevers, A. Yoldas ..., Reporting group: GaiaAlerts, Data source group: GaiaAlerts

2024aazx RA=07:03:57.730, DEC=-02:12:37.22, Discovery date=2024-11-04 10:29:16.800, Discovery mag=13.3 ABMag, Filter: G - Gaia, Reporter: S.T. Hodgkin, E. Breedt, A. Delgado, D.L. Harrison, M. van Leeuwen, G. Rixon, T. Wevers, A. Yoldas ..., Reporting group: GaiaAlerts, Data source group: GaiaAlerts

The alert comes with the transient's ID, RA/DEC coordinates, discovery time, discovery magnitude, followed by other information.

Curiosity about the distribution of transients provided the motivation to code a rough plotting application (C# Windows GUI) which would accept a cut-and-paste of the transient/s information lines and parse them into names and RA/DEC coordinates.  The application then plots them on a RA/DEC graph which has a Hydrogen Line image as the background (which provides a guide to the position of the Milky Way).

As new transient alerts arrive they can be added to the list and the plot updated to show the new entries.

An example result is shown below...

Typical Plot (~100 transients) with Names Shown

As can be seen as the number of transients increase there is confusion due to the names overlapping. An option to only plot the points is provided as shown below...

Typical Plot Without Names

As would be expected the highest density is near the Galactic Centre, but interestingly this density is - so far - not overwhelming higher than elsewhere.

It will be interesting to see how the plotting progresses over time as new transients are added.

Some extra functions may be added at a later date. For example - display only the newest object or objects for the purpose of seeing whether they can be seen in the Seestar S50.

NOTE: The TNS alerts come from telescopes which monitor a very large area of the sky. The likelihood of an amateur telescope with limited FOV discovering a transient are vanishingly small. Of course it is possible - but the likelihood of beating the professional observations is not great.

Observation Aid: SkyViewAltAz - Update #3

 When planning observation runs there is - unfortunately - a further factor that needs to be taken into account besides the visibility of targets through the various partial sky views available on the home block. That further factor is - of course - a clear sky.

While the application works well at its purpose of showing possible targets for the night, the presence of a clear sky was not included - which required looking up various websites.

The online website 'Clear Outside' provides a graphic which gives a forecast for the next couple of days in terms of skies suitable for observations. This graphic has been added to the 'SkyViewAltAz' application. Some re-arrangement of the GUI was also done to fit the graphic in.

Conveniently the 'Clear Outside' graphic is updated every hour and provides a prediction of cloud cover in general area of the home observatory.

Observation Aid: SkyViewAltAz - Update #2

Some added functionality and a bug fix. The added functionality extends the search function to actually select the object - if found - and display its data. Checkboxes are provided for a full data search (on by default) and also to 'lock' the found object - to allow changing the date and time without updating the drop-down object list. Some re-arranging and resizing of the search function text boxes has also been done.

The position of the Sun and Moon are now calculated and representative filled circles (yellow for the Sun - white for the Moon) are plotted on the display. The current elevation of both of these objects is displayed (in green if below the horizon - red if above the horizon).

The bug fix prevents off-screen plotting (outside the PictureBox component) drawing spurious lines (see previous post image).  Instead of plotting the whole range at once, the plot points are tested to see if they are outside the PictureBox client rectangle and - if so - the segment up until that point is plotted.  Points are then continued to be scanned until a point is found inside the client rectangle and then the process repeats until all 'on-screen' points have been plotted. The granularity of the plotting points means that sometimes the plotted lines end before they have reached the edge of the PictureBox client rectangle - but this is considered the lesser of the two evils.

Another change is to the large image which is displayed on the right (nominally a screenshot from Stellarium) to indicate the size of the object w.r.t. the Seestar's FOV. As actual observations of an object are done, the object Stellarium screenshot will be replaced with an actual suitable Seestar observation image.

Apologies for the programming-oriented details. When the clouds stop coming over at night it will be back to pretty pictures...

Observation Aid: SkyViewAltAz - Update #1

 After evaluating the prototype version of SkyViewAltAz, a number of changes and additions were made. The intent is to provide a tool to assist in planning observation sessions - initially for use with the Seestar S50.

The current version provides time controls, selection of the various sky views from the home block (plotted on an Az/El grid), the path through the sky views for a selected object as well as various types of information (altitude/ azimuth, current field rotation, etc).

There are also filter options which limit which objects are populated in a drop down list, e.g., a range before and after LST, visibility in sky views - or visible from latitude 34 S (or no filters).

A thumbnail captured from the web (Wikipedia) is displayed to give an idea of the object itself - but of more use is a larger screenshot image (Stellarium) of the appearance of the object in the field of view (FOV) of the Seestar S50. This is very useful as images found on the web are the result from a wide variety of telescope FOVs - so, an object which looks like an interesting target judging from an image seen on the web might actually be from a large telescope with a very small FOV - but when viewed on a Seestar S50 may be just a dot in its much larger FOV.

SkyViewAzEl GUI (click on the image for a larger view)

All I need now is for the clouds to go away...

NOTE: the details provided here of SkyViewAzEl are informational only and primarily for my own documentation. Please don't ask for copies - I don't ever share my code as I have neither the time nor inclination to provide same - not to mention copyright issues (Wikipedia, Stellarium). To avoid being offended by a non-response - don't ask.