One of the challenges of observing in the near-IR / optical is field identification. In the case of the Apache Point Observatory 3.5m, the "raw" pointing - i.e., if you enter a coordinate and press "slew" - is usually good to within ~1 arcminute. However, once you're on the target field, it's up to you as the observer to identify the exact location within the 5x5' field to observe. This proves quite challenging in crowded fields, especially with rotation. It is far more difficult, though, in sparse fields when your target is a faint emission line feature - there will be no corresponding light in your guider image. But you still want ~arcsecond pointing accuracy. I think this can be achieved by using the astrometry.net source recognition and field identification tools, but highly constrained to be within ~10' of the target field. The WCS coordinates would then be applied to the guider image, and the target location identified and translated into a telescope pointing offset. This technique is probably not needed for most spectroscopic observations (e.g., of bright point sources). However, for slit-scan-mapping or observations of faint point sources, this approach provides the opportunity to do fast-switching with a bright calibration star so that telluric correction can be provided on a short (~5-10 minute) timescale, as is needed for truly accurate calibration.
#6 on Astro-ph today
IRAS 05358 on astro-ph. Check out my page on the region too.
Acquiring DSS images
This is the way to get DSS images: ESO's batch downloader
astro-better post
I contributed to a post on Astro Better asking about mosaicing software.
Awk sexagesimal to decimal conversion
In VIM I often need to convert columns of RA/Dec from Sexagesimal into Decimal format. %!awk '{ra = ($2+$3/60+$4/3600)*15; dec = $6+$7/60+$8/3600; print $1,"ra=",ra,", dec= ",$5,dec}' The far more irritating inverse operation: `` %!awk '{h=($2/15); h=h-(h%1); m=($2-h*15)/15*60; m=m-(m%1); s=($2-h*15-m*15/60)/15*3600; d=-($3-$3%1); am=(-$3-d)*60; am=am-(am%1); as=(-$3-d-am/60)*3600; printf "%s %02i:%02i:%02.2f, -%02i:%02i:%02.2f %s %s %sn" , $1,h,m,s,d,am,as,$4,$5,$6}' ``
EVLA information
It has been really hard to find EVLA information like beam size, largest angular scale, sensitivity, etc. on the VLA pages because all of the google searches point to old VLA information. The most useful and recent EVLA information on beam size and largest angular scale is here
First paper accepted
My Comps II paper on IRAS 05358+3543 was accepted by ApJ on Wednesday. It will show up on arxiv in a few days and I'll post the link then. Unfortunately, there were significant problems rendering the paper, so I recommend downloading my version. Also, working on the HISA KDA... I have a nice section of cutouts
Galaxy Map
If you're ever interested in seeing a face-on view of the Milky Way, check out the Spitzer press release. This link is very surprisingly hard to find on google.
IDL-to-Python
astrobetter started up an idl-to-python guide on their wiki.
Lunar Occultation Hi-Res measurements
The folks at the VLT have come up with a means of achieving extremely high resolution from the ground: Observe when the moon occults a source and how long the occultation takes. Sweet. This was applied in the galactic center first, of course: Observations of binaries in GC Additional observations in GC
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