astro query:docs

- Index
- Modules

### Navigation

- next »
- « previous |
- astroquery v0.4.11 »
- FIRST Queries (`astroquery.image_cutouts.first`)

# FIRST Queries (`astroquery.image_cutouts.first`)

## Getting started

This module may be used to fetch image cutouts in the FITS format from the Faint Images of the Radio Sky at Twenty-cm (FIRST) VLA radio survey. The only required parameter is the target you wish to search for. This may be specified as a name - which is resolved online via astropy functions or as coordinates using any of the coordinate systems available in `astropy.coordinates`. The FITS image is returned as an `HDUList` object. Here is a sample query:

    >>> from astroquery.image_cutouts.first import First
    >>> from astropy import coordinates
    >>> from astropy import units as u
    >>> image = First.get_images(coordinates.SkyCoord(162.530*u.deg, 30.677*u.deg,
    ...                                                frame='icrs'))
    >>> image

    [<astropy.io.fits.hdu.image.PrimaryHDU object at 0x11c189390>]

There are some other optional parameters that you may additionally specify. For instance the image size may be specified by setting the `image_size` parameter. It defaults to 1 arcmin, but may be set to another value using the appropriate `Quantity` object.

## Troubleshooting

If you are repeatedly getting failed queries, or bad/out-of-date results, try clearing your cache:

    >>> from astroquery.image_cutouts.first import First
    >>> First.clear_cache()

If this function is unavailable, upgrade your version of astroquery. The `clear_cache` function was introduced in version 0.4.7.dev8479.

## Reference/API

### astroquery.image_cutouts.first Package

#### FIRST Image Query Tool

Revision History

Originally contributed by:

  Rick White (rlw@stsci.edu)

#### Classes

`FirstClass`() |
`Conf`() | Configuration parameters for `astroquery.image_cutouts.first`.