Thanks to Mike O'Shaughnessy it's possible for this file to be hosted
for a little while.

The 41 Mb zipped file 2MASSX.zip is available for download from

http://www.astronomy-resources.com/sub2mass/

The zip mostly consists of the file 2MASSX.dat, which is a subset of
data from the 2MASS Extended Source Catalogue enabling display
suitable to Guide for 1.65 million objects. Right click and Save As
in the browser. A test download has been done, and the downloaded zip
file checked for consistency, and it passed. It'll occupy ~ 150 Mb of
hard drive.

Two additional small files are the TDF file for the dataset and a
readme acknowledging the 2MASS project and giving details of how to
use the data within Guide.

Dark red orientated ellipses to isophotal mag derived scale are
presented, with NIR (near infrared) photometry details. The main
magnitude given is quoted from the Ks mag.

The 2MASSX names are quoted and the centroid RA and Dec to J2000.

Although many objects will also be visible in the optical, some will
not be so, or will be much fainter in the optical.

The full, multifield, 2MASSX dataset served via IRSA/IPAC gives much
extra data, but these are primarily to do with the experiment, and
little detail is given with respect to object type.

Basically it is an Extended, as opposed to _Point_, source catalogue,
that is it was built from objects that had size on 2MASS images
(though the very large objects are often either not included or broken
up into several objects). On the whole, unlike some such data sources
in the optical, the objects are real and not artefacts.

Links to 2MASS images and SDSS images (where applicable) and the NED
galaxy database are also available from More Info, but not all objects
are necessarily galaxies, especially in Milky Way fields, where they
can be one of several other deepsky objects, especially nebulae.

It's a dataset of mixed utility to the visual deepsky observer,
containing some things not included in other datasets, but also things
likely invisible in the optical, as well as things already well
catalogued. But at ~ 1.65 million objects over the whole sky there
should be a little bit of something there for everyone.

I've personally often found the 2MASS image based NIR sizes to be
nearer to what one truly sees in the visual with respect to scale,
whereas optical images, such as POSS and the like, are often more
exposed or overexposed and thus larger than what one sees at the
eyepiece (except possibly in exceptional seeing). If I've explained
that properly...

Anyway, it's there for those interested, hope it's of use/interest to
some.

The tdf should work fine if the file is placed as described in the
readme. I'll be away from my machine for around a day, so if any
problems arise, sorry for the delay in response.

Cheers

John