# AstrometryNetClass¶

class astroquery.astrometry_net.AstrometryNetClass[source]

Perform queries to the astrometry.net service to fit WCS to images or source lists.

Show a warning message if the API key is not in the configuration file.

Attributes Summary

 API_URL TIMEOUT URL api_key Return the Astrometry.net API key. empty_settings Construct a dict of settings using the defaults

Methods Summary

 monitor_submission(submission_id[, …]) Monitor the submission for completion. There are a ton of options available for solving. solve_from_image(image_file_path[, …]) Plate solve from an image, either by uploading the image to astrometry.net or by finding sources locally using photutils and solving with source locations. solve_from_source_list(x, y, image_width, …) Plate solve from a list of source positions.

Attributes Documentation

API_URL = 'http://nova.astrometry.net/api'
TIMEOUT = 120
URL = 'http://nova.astrometry.net'
api_key

Return the Astrometry.net API key.

empty_settings

Construct a dict of settings using the defaults

Methods Documentation

login()
monitor_submission(submission_id, solve_timeout=120)[source]

Monitor the submission for completion.

Parameters
submission_idint or str

Submission ID number from astrometry.net.

solve_timeoutint

Time, in seconds, to wait for the astrometry.net solver to find a solution.

Returns
None or astropy.io.fits.Header

The contents of the returned object depend on whether the solve succeeds or fails. If the solve succeeds the header with the WCS solution generated by astrometry.net is returned. If the solve fails then an empty dictionary is returned. See below for the outcome if the solve times out.

Raises
TimeoutError

Raised if astroquery.astrometry_net.AstrometryNetClass.TIMEOUT is exceeded before the solve either succeeds or fails. The second argument in the exception is the submission ID.

show_allowed_settings()[source]

There are a ton of options available for solving. This displays them in a nice way.

solve_from_image(image_file_path, force_image_upload=False, ra_key=None, dec_key=None, ra_dec_units=None, fwhm=3, detect_threshold=5, solve_timeout=120, **settings)[source]

Plate solve from an image, either by uploading the image to astrometry.net or by finding sources locally using photutils and solving with source locations.

Parameters
image_file_pathstr or Path object

Path to the image.

If True, upload the image to astrometry.net even if it is possible to detect sources in the image locally. This option will almost always take longer than finding sources locally. It will even take longer than installing photutils and then rerunning this.

Even if this is False the image will be upload unless photutils is installed.

ra_keystr, optional

Name of the key in the FITS header that contains right ascension of the image. The ra can be specified using the center_ra setting instead if desired.

dec_keystr, optional

Name of the key in the FITS header that contains declination of the image. The dec can be specified using the center_dec setting instead if desired.

ra_dec_unitstuple, optional

Tuple specifying the units of the right ascension and declination in the header. The default value is ('hour', 'degree').

solve_timeoutint

Time, in seconds, to wait for the astrometry.net solver to find a solution.

For a list of the remaining settings, use the method
~AstrometryNetClass.show_allowed_settings.
solve_from_source_list(x, y, image_width, image_height, solve_timeout=120, **settings)[source]

Plate solve from a list of source positions.

Parameters
xlist-like

List of x-coordinate of source positions.

ylist-like

List of y-coordinate of source positions.

image_widthint

Size of the image in the x-direction.

image_heightint

Size of the image in the y-direction.

solve_timeoutint

Time, in seconds, to wait for the astrometry.net solver to find a solution.

For a list of the remaining settings, use the method
~AstrometryNetClass.show_allowed_settings.