Searching for Data available for the bright galaxy M51 (developed by M. Allen)

Uses Aladin, Simbad, VizieR, TOPCAT and VOSpec.

Searching for available data for the bright galaxy M51

• launch Aladin, TOPCAT, VOSpec
• search for images of the bright galaxy M51 in Aladin
• open the Server Selector by clicking on the Load button, then try the various image servers:
  • the Aladin Image Server
  • explore Skyview
  • try Sloan
• select allVO; explore allVO
  • tick off Catalogues and Spectra and open the Server list (click on "Detailed list ...")
  • the button marked "?" next to each Registry will give information about the Registry
• after selecting a few images, make a colour composite image using the "rgb" button, 7rd from the bottom in the vertical tool bar, right next to the image window; select the three images and "Create"
• use the multi-view windows to manage the various images you have in the 'stack'
• try the match button at the bottom of the image window to align the image for synchronized zooming
• go back to single image view and try the transparency control for viewing images overlaid on each other
• overlay as SIMBAD identifications using the SIMBAD link in the Server Selector window
  • try 'All objects' for a simple listsing of the IDs
  • click on a SIMBAD object or select a list of objects and see the details in tabular form below the image window
  • highlight the Simbad plane and click on "filter"
  • try the various filtering options (optional - open the properties'" window for the Simbad plane to see or edit the filter)
• filtering of sources can also be done interactively with TOPCAT; send the SIMBAD plane to TOPCAT (right-click on the plane in the stack, and 'Broadcast selected tables to..'
• view the table values in TOPCAT by selecting Views -> Table Data or by clicking on the 4th button from the top left
• make a plot of the positions and try the area selection tools to select a number of points in the plot, then create a subset; note how the selected subset may be transmitted back to Aladin to highlight sources from the original Simbad plane
• make a subset of the HII regions, and send the table back to Aladin using the TOPCAT Interop menu
  • place the cursor on any of the HII regions in Aladin and see how the corresponding row is highlighted in TOPCAT
• search for spectra available in the VO with the 'all VO' button in the server selector window.
• find spectra available from the Hubble Space Telescope, and view the positions of the spectra (and sometimes the spectral slit aperture) on the image; make a plane containing all the spectra positions, and cross match these with the positions of the HII regions
• start VOSpec (Web Start: http://esavo.esac.esa.int/webstart/VOSpec.jnlp) and display some of the spectra, by clicking on the spectra in the server selector window, and 'Load in -> VOSpec'.
• check VizieR for more detailed catalogues of HII emitting regions in M51; this can be done via Aladin or via the more detailed VizieR interface
• (Advanced - compile a list of bright HII regions in M51 and query VizieR with this list)