VHS (Vista Hemisphere Survey)
Description
The Vista Hemisphere Survey (VHS) is imaging the entire southern hemisphere of the sky, with the exception of the areas already covered by the VIKING and VVV surveys, in two near-infrared bands as well as some other areas for special purposes. The resulting data are about 4 magnitudes (forty times) deeper than the earlier 2MASS and DENIS surveys. The main aims of the survey are to examine low mass and nearby stars, to study the merger history of our Milky Way, to measure the properties of dark energy through the examination of large-scale structure and to search for high-redshift quasars.
The vhs_dr5.vhs_cat_v3 table has been crossmatched against our default reference datasets within a 1.5 arcsec radius, nearest neighbor only. These tables will appear with x1p5 in their name in our table browser. Example: vhs_dr5.x1p5__vhs_cat_v3__gaia_dr3__gaia_source.
Data Releases
Fifth Data Release (VHS DR5)
The fifth Data Release, third version of the Vista Hemisphere Survey (VHS) from the ESO-VISTA telescope is stored in Data Lab as a photometric reference dataset.
| VHS DR5 Tables | |
|---|---|
| Table Name | Description |
| vhs_cat_v3 | This multi-band source catalogue provides aperture photometry in four near infrared broad-band filters: Y, J, H and Ks for almost 1.4 billion detections. The total coverage of the VHS survey is almost 17000 square degrees in the South Hemisphere. |
For a full description of VHS DR5, please visit the ESO data page (https://www.eso.org/qi/catalog/show/290).
This data has been downloaded from ESO on 2021-05-12 and are re-distributed unmodified with the exception of some columns added by NOIRLab according to the terms of the Creative Commons Attribution 4.0 International license (CC BY 4.0). Note that we have removed the following columns, since they were entirely empty:
- hpsfmag
- hpsfmagerr
- hsermag2d
- hsermag2derr
- jpsfmag
- jpsfmagerr
- jsermag2d
- jsermag2derr
- kspsfmag
- kspsfmagerr
- kssermag2d
- kssermag2derr
- ypsfmag
- ypsfmagerr
- ysermag2d
- ysermag2derr
Further, we have added the following columns to improve usability within Data Lab:
- elon
- elat
- htm9
- ring256
- nest4096
- random_id
Data Access
The VHS data are accessible by a variety of means:
Data Lab Table Access Protocol (TAP) service
TAP provides a convenient access layer to the VHS catalog database. TAP-aware clients (such as TOPCAT) can point to https://datalab.noirlab.edu/tap, select the vhs_dr5 database, and see the database tables and descriptions. You can also view the VHS tables and descriptions in the Data Lab table browser.
Data Lab Query Client
The Query Client is available as part of the Data Lab software distribution. The Query Client provides a Python API to Data Lab database services. These services include anonymous and authenticated access through synchronous or asynchronous queries of the catalog made directly to the database. Additional Data Lab services for registered users include personal database storage and storage through the Data Lab VOSpace.
The Query Client can be called from a Jupyter Notebook on the Data Lab Notebook server. Example notebooks are provided to users upon creation of their user account (register here), and are also available to browse on GitHub at https://github.com/astro-datalab/notebooks-latest.
Jupyter Notebook Server
The Data Lab Jupyter Notebook server (authenticated service) contains examples of how to access and visualize the VHS catalog:
Acknowledgments
All users are required to acknowledge the source of the data with an appropriate citation in their publications, using the following text:
"The VISTA Hemisphere Survey data products served at Astro Data Lab are based on observations collected at the European Organisation for Astronomical Research in the Southern Hemisphere under ESO programme 179.A-2010, and/or data products created thereof."
