This notebook tutorial demonstrates the process of querying IRSA's Simple Image Access v2 (SIAv2) service for the Spitzer Enhanced Imaging Products (SEIP), making a cutout image (thumbnail), and displaying the cutout.
By the end of this tutorial, you will:
The Spitzer Enhanced Imaging Products (SEIP) include Super Mosaics combining data from multiple programs if appropriate, and a high-reliability Source List of compact objects. The SEIP include data from the four channels of IRAC (3.6, 4.5, 5.8, 8 microns) and the 24 micron channel of MIPS. More information about the SEIP can be found at:
https://irsa.ipac.caltech.edu/data/SPITZER/Enhanced/SEIP/
The NASA/IPAC Infrared Science Archive (IRSA) at Caltech is the archive for SEIP images and catalogs. The SEIP images that are the subject of this tutorial are made accessible via the International Virtual Observatory Alliance (IVOA) Simple Image Access (SIA) protocol. IRSA's SEIP SIA service is registered in the NASA Astronomical Virtual Observatory (NAVO) Directory. Based on the registered information, the Python package pyvo can be used to query the SEIP SIA service for a list of images that meet specified criteria, and standard Python libraries can be used to download and manipulate the images. Other datasets at IRSA are available through other SIA services:
https://irsa.ipac.caltech.edu/docs/program_interface/api_images.html
import pyvo as vo
from astropy.coordinates import SkyCoord
from astropy.nddata import Cutout2D
from astropy.wcs import WCS
import astropy.units as u
import matplotlib.pyplot as plt
from astropy.utils.data import download_file
from astropy.io import fits
Set images to display in the notebook
%matplotlib inline
Define coordinates of a bright star
ra = 314.30417
dec = 77.595559
pos = SkyCoord(ra=ra, dec=dec, unit='deg')
Start at STScI VAO Registry at https://vao.stsci.edu/keyword-search/
Search on "seip"
Locate the COLLECTION=spitzer_seip from the SIA2 URL https://irsa.ipac.caltech.edu/SIA?COLLECTION=spitzer_seip&
To work with pyvo 1.4, define this SIAv2 service and use the collection argument separately
seip_service2= vo.dal.sia2.SIAService('https://irsa.ipac.caltech.edu/SIA')
Search for images covering within 10 arcseconds of the star
im_table = seip_service2.search(pos=(pos.ra.deg, pos.dec.deg, 10*u.arcsec),
collection='spitzer_seip')
Display the table of images that is returned
im_table.to_table()
| s_region | obs_collection | obs_intent | algorithm_name | facility_name | facility_keywords | instrument_name | instrument_keywords | environment_photometric | proposal_id | proposal_pi | proposal_project | proposal_title | target_name | target_type | target_standard | target_moving | target_keywords | calib_level | dataproduct_type | obs_release_date | s_xel1 | s_xel2 | position_samplesize | position_timedependent | energy_emband | energy_bandpassname | t_min | t_max | t_exptime | t_resolution | t_xel | access_url | access_format | access_estsize | obs_id | obs_publisher_did | s_ra | s_dec | s_fov | s_resolution | em_min | em_max | em_res_power | em_xel | pol_states | pol_xel | o_ucd |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| deg | arcsec | d | d | s | s | kbyte | deg | deg | deg | arcsec | m | m | |||||||||||||||||||||||||||||||||||
| object | object | object | object | object | object | object | object | bool | object | object | object | object | object | object | bool | bool | object | int16 | object | object | int64 | int64 | float64 | bool | object | object | float64 | float64 | float64 | float64 | int64 | object | object | int64 | object | object | float64 | float64 | float64 | float64 | float64 | float64 | float64 | int64 | object | int64 | object |
| POLYGON ICRS 316.0670347 77.0402173 316.1473632 77.7956756 313.3483063 77.7956771 313.4286176 77.0402187 316.0670347 77.0402173 | spitzer_seip | science | mosaic | Spitzer Space Telescope | IRAC | -- | Spitzer | Spitzer Enhanced Imaging Products | field | False | False | 3 | image | 2013-12-19 00:00:00 | 3550 | 4534 | 0.600012 | False | Infrared | IRAC1 | -- | -- | -- | -- | -- | https://irsa.ipac.caltech.edu/data/SPITZER/Enhanced/SEIP/images/4/0019/40019821/9/40019821-9/40019821.40019821-9-short.IRAC.1.cov.fits | image/fits | 64393 | 35f5f56a-0a41-4f56-8061-5b2906e56088 | ivo://irsa.ipac/spitzer_seip/40019821.40019821-9.IRAC | 314.7482131 | 77.4212892 | 0.668670817418952 | 1.66 | 3.17e-06 | 3.92e-06 | 4.8 | -- | -- | ||||||||
| POLYGON ICRS 316.0670347 77.0402173 316.1473632 77.7956756 313.3483063 77.7956771 313.4286176 77.0402187 316.0670347 77.0402173 | spitzer_seip | science | mosaic | Spitzer Space Telescope | IRAC | -- | Spitzer | Spitzer Enhanced Imaging Products | field | False | False | 3 | image | 2013-12-19 00:00:00 | 3550 | 4534 | 0.600012 | False | Infrared | IRAC1 | -- | -- | -- | -- | -- | https://irsa.ipac.caltech.edu/data/SPITZER/Enhanced/SEIP/images/4/0019/40019821/9/40019821-9/40019821.40019821-9-short.IRAC.1.median_mosaic_unc.fits | image/fits | 64393 | 35f5f56a-0a41-4f56-8061-5b2906e56088 | ivo://irsa.ipac/spitzer_seip/40019821.40019821-9.IRAC | 314.7482131 | 77.4212892 | 0.668670817418952 | 1.66 | 3.17e-06 | 3.92e-06 | 4.8 | -- | -- | ||||||||
| POLYGON ICRS 316.0670347 77.0402173 316.1473632 77.7956756 313.3483063 77.7956771 313.4286176 77.0402187 316.0670347 77.0402173 | spitzer_seip | science | mosaic | Spitzer Space Telescope | IRAC | -- | Spitzer | Spitzer Enhanced Imaging Products | field | False | False | 3 | image | 2013-12-19 00:00:00 | 3550 | 4534 | 0.600012 | False | Infrared | IRAC1 | -- | -- | -- | -- | -- | https://irsa.ipac.caltech.edu/data/SPITZER/Enhanced/SEIP/images/4/0019/40019821/9/40019821-9/40019821.40019821-9-short.IRAC.1.median_mosaic.fits | image/fits | 64393 | 35f5f56a-0a41-4f56-8061-5b2906e56088 | ivo://irsa.ipac/spitzer_seip/40019821.40019821-9.IRAC | 314.7482131 | 77.4212892 | 0.668670817418952 | 1.66 | 3.17e-06 | 3.92e-06 | 4.8 | -- | -- | ||||||||
| POLYGON ICRS 316.0670347 77.0402173 316.1473632 77.7956756 313.3483063 77.7956771 313.4286176 77.0402187 316.0670347 77.0402173 | spitzer_seip | science | mosaic | Spitzer Space Telescope | IRAC | -- | Spitzer | Spitzer Enhanced Imaging Products | field | False | False | 3 | image | 2013-12-19 00:00:00 | 3550 | 4534 | 0.600012 | False | Infrared | IRAC1 | -- | -- | -- | -- | -- | https://irsa.ipac.caltech.edu/data/SPITZER/Enhanced/SEIP/images/4/0019/40019821/9/40019821-9/40019821.40019821-9-short.IRAC.1.std.fits | image/fits | 64393 | 35f5f56a-0a41-4f56-8061-5b2906e56088 | ivo://irsa.ipac/spitzer_seip/40019821.40019821-9.IRAC | 314.7482131 | 77.4212892 | 0.668670817418952 | 1.66 | 3.17e-06 | 3.92e-06 | 4.8 | -- | -- | ||||||||
| POLYGON ICRS 316.0670347 77.0402173 316.1473632 77.7956756 313.3483063 77.7956771 313.4286176 77.0402187 316.0670347 77.0402173 | spitzer_seip | science | mosaic | Spitzer Space Telescope | IRAC | -- | Spitzer | Spitzer Enhanced Imaging Products | field | False | False | 3 | image | 2013-12-19 00:00:00 | 3550 | 4534 | 0.600012 | False | Infrared | IRAC4 | -- | -- | -- | -- | -- | https://irsa.ipac.caltech.edu/data/SPITZER/Enhanced/SEIP/images/4/0019/40019821/9/40019821-9/40019821.40019821-9-short.IRAC.4.std.fits | image/fits | 64393 | 35f5f56a-0a41-4f56-8061-5b2906e56088 | ivo://irsa.ipac/spitzer_seip/40019821.40019821-9.IRAC | 314.7482131 | 77.4212892 | 0.668670817418952 | 1.98 | 6.44e-06 | 9.28e-06 | 2.8 | -- | -- | ||||||||
| POLYGON ICRS 316.0670347 77.0402173 316.1473632 77.7956756 313.3483063 77.7956771 313.4286176 77.0402187 316.0670347 77.0402173 | spitzer_seip | science | mosaic | Spitzer Space Telescope | IRAC | -- | Spitzer | Spitzer Enhanced Imaging Products | field | False | False | 3 | image | 2013-12-19 00:00:00 | 3550 | 4534 | 0.600012 | False | Infrared | IRAC4 | -- | -- | -- | -- | -- | https://irsa.ipac.caltech.edu/data/SPITZER/Enhanced/SEIP/images/4/0019/40019821/9/40019821-9/40019821.40019821-9-short.IRAC.4.unc.fits | image/fits | 64393 | 35f5f56a-0a41-4f56-8061-5b2906e56088 | ivo://irsa.ipac/spitzer_seip/40019821.40019821-9.IRAC | 314.7482131 | 77.4212892 | 0.668670817418952 | 1.98 | 6.44e-06 | 9.28e-06 | 2.8 | -- | -- | ||||||||
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| POLYGON ICRS 315.0377119 77.538868 315.0949554 78.3071067 313.2110739 78.307107 313.2683115 77.5388683 315.0377119 77.538868 | spitzer_seip | science | mosaic | Spitzer Space Telescope | MIPS | -- | Spitzer | Spitzer Enhanced Imaging Products | field | False | False | 3 | image | 2013-12-19 00:00:00 | 561 | 1129 | 2.4500016 | False | Infrared | MIPS24 | -- | -- | -- | -- | -- | https://irsa.ipac.caltech.edu/data/SPITZER/Enhanced/SEIP/images/4/0019/40019821/3/40019821-13/40019821.40019821-13.MIPS.1.cov.fits | image/fits | 2543 | 35f5fb96-863d-4c20-8e92-c40189d72f38 | ivo://irsa.ipac/spitzer_seip/40019821.40019821-13.MIPS | 314.1546397 | 77.9241351 | 0.541616976931299 | 6.0 | 2.08e-05 | 2.61e-05 | 4.5 | -- | -- | ||||||||
| POLYGON ICRS 315.0377119 77.538868 315.0949554 78.3071067 313.2110739 78.307107 313.2683115 77.5388683 315.0377119 77.538868 | spitzer_seip | science | mosaic | Spitzer Space Telescope | MIPS | -- | Spitzer | Spitzer Enhanced Imaging Products | field | False | False | 3 | image | 2013-12-19 00:00:00 | 561 | 1129 | 2.4500016 | False | Infrared | MIPS24 | -- | -- | -- | -- | -- | https://irsa.ipac.caltech.edu/data/SPITZER/Enhanced/SEIP/images/4/0019/40019821/3/40019821-13/40019821.40019821-13.MIPS.1.unc.fits | image/fits | 2543 | 35f5fb96-863d-4c20-8e92-c40189d72f38 | ivo://irsa.ipac/spitzer_seip/40019821.40019821-13.MIPS | 314.1546397 | 77.9241351 | 0.541616976931299 | 6.0 | 2.08e-05 | 2.61e-05 | 4.5 | -- | -- | ||||||||
| POLYGON ICRS 315.0377119 77.538868 315.0949554 78.3071067 313.2110739 78.307107 313.2683115 77.5388683 315.0377119 77.538868 | spitzer_seip | science | mosaic | Spitzer Space Telescope | MIPS | -- | Spitzer | Spitzer Enhanced Imaging Products | field | False | False | 3 | image | 2013-12-19 00:00:00 | 561 | 1129 | 2.4500016 | False | Infrared | MIPS24 | -- | -- | -- | -- | -- | https://irsa.ipac.caltech.edu/data/SPITZER/Enhanced/SEIP/images/4/0019/40019821/3/40019821-13/40019821.40019821-13.MIPS.1.mosaic.fits | image/fits | 2543 | 35f5fb96-863d-4c20-8e92-c40189d72f38 | ivo://irsa.ipac/spitzer_seip/40019821.40019821-13.MIPS | 314.1546397 | 77.9241351 | 0.541616976931299 | 6.0 | 2.08e-05 | 2.61e-05 | 4.5 | -- | -- | ||||||||
| POLYGON ICRS 315.0377119 77.538868 315.0949554 78.3071067 313.2110739 78.307107 313.2683115 77.5388683 315.0377119 77.538868 | spitzer_seip | science | mosaic | Spitzer Space Telescope | MIPS | -- | Spitzer | Spitzer Enhanced Imaging Products | field | False | False | 3 | image | 2013-12-19 00:00:00 | 561 | 1129 | 2.4500016 | False | Infrared | MIPS24 | -- | -- | -- | -- | -- | https://irsa.ipac.caltech.edu/data/SPITZER/Enhanced/SEIP/images/4/0019/40019821/3/40019821-13/40019821.40019821-13.MIPS.1.extmask.fits | image/fits | 642 | 35f5fb96-863d-4c20-8e92-c40189d72f38 | ivo://irsa.ipac/spitzer_seip/40019821.40019821-13.MIPS | 314.1546397 | 77.9241351 | 0.541616976931299 | 6.0 | 2.08e-05 | 2.61e-05 | 4.5 | -- | -- | ||||||||
| POLYGON ICRS 315.0377119 77.538868 315.0949554 78.3071067 313.2110739 78.307107 313.2683115 77.5388683 315.0377119 77.538868 | spitzer_seip | science | mosaic | Spitzer Space Telescope | MIPS | -- | Spitzer | Spitzer Enhanced Imaging Products | field | False | False | 3 | image | 2013-12-19 00:00:00 | 561 | 1129 | 2.4500016 | False | Infrared | MIPS24 | -- | -- | -- | -- | -- | https://irsa.ipac.caltech.edu/data/SPITZER/Enhanced/SEIP/images/4/0019/40019821/3/40019821-13/40019821.40019821-13.MIPS.1.std.fits | image/fits | 2543 | 35f5fb96-863d-4c20-8e92-c40189d72f38 | ivo://irsa.ipac/spitzer_seip/40019821.40019821-13.MIPS | 314.1546397 | 77.9241351 | 0.541616976931299 | 6.0 | 2.08e-05 | 2.61e-05 | 4.5 | -- | -- | ||||||||
| POLYGON ICRS 315.0377119 77.538868 315.0949554 78.3071067 313.2110739 78.307107 313.2683115 77.5388683 315.0377119 77.538868 | spitzer_seip | science | mosaic | Spitzer Space Telescope | MIPS | -- | Spitzer | Spitzer Enhanced Imaging Products | field | False | False | 3 | image | 2013-12-19 00:00:00 | 561 | 1129 | 2.4500016 | False | Infrared | MIPS24 | -- | -- | -- | -- | -- | https://irsa.ipac.caltech.edu/data/SPITZER/Enhanced/SEIP/images/4/0019/40019821/3/40019821-13/40019821.40019821-13.MIPS.1.brightmask.fits | image/fits | 642 | 35f5fb96-863d-4c20-8e92-c40189d72f38 | ivo://irsa.ipac/spitzer_seip/40019821.40019821-13.MIPS | 314.1546397 | 77.9241351 | 0.541616976931299 | 6.0 | 2.08e-05 | 2.61e-05 | 4.5 | -- | -- | ||||||||
| POLYGON ICRS 315.0377119 77.538868 315.0949554 78.3071067 313.2110739 78.307107 313.2683115 77.5388683 315.0377119 77.538868 | spitzer_seip | science | mosaic | Spitzer Space Telescope | MIPS | -- | Spitzer | Spitzer Enhanced Imaging Products | field | False | False | 3 | image | 2013-12-19 00:00:00 | 561 | 1129 | 2.4500016 | False | Infrared | MIPS24 | -- | -- | -- | -- | -- | https://irsa.ipac.caltech.edu/data/SPITZER/Enhanced/SEIP/images/4/0019/40019821/3/40019821-13/40019821.40019821-13.MIPS.1.cov.fits | image/fits | 2543 | 35f5fb96-863d-4c20-8e92-c40189d72f38 | ivo://irsa.ipac/spitzer_seip/40019821.40019821-13.MIPS | 314.1546397 | 77.9241351 | 0.541616976931299 | 6.0 | 2.08e-05 | 2.61e-05 | 4.5 | -- | -- |
Let's search the image results for a short-exposure IRAC Ch3 mosaic.
for i in range(len(im_table)):
if im_table[i].getdataurl().endswith('short.IRAC.3.mosaic.fits'):
break
print(im_table[i].getdataurl())
https://irsa.ipac.caltech.edu/data/SPITZER/Enhanced/SEIP/images/4/0019/40019821/9/40019821-9/40019821.40019821-9-short.IRAC.3.mosaic.fits
Download the image and open it in Astropy
fname = download_file(im_table[i].getdataurl(), cache=True)
image1 = fits.open(fname)
wcs = WCS(image1[0].header)
cutout = Cutout2D(image1[0].data, pos, (60, 60), wcs=wcs)
wcs = cutout.wcs
fig = plt.figure()
ax = fig.add_subplot(1, 1, 1, projection=wcs)
ax.imshow(cutout.data, cmap='gray_r', origin='lower', vmax = 10)
ax.scatter(ra, dec, transform=ax.get_transform('fk5'), s=500, edgecolor='red', facecolor='none')
<matplotlib.collections.PathCollection at 0x114fe5b50>
Search the SEIP Source List using IRSA Gator service, find an object of interest and repeat the steps above to extract cutouts in all four IRAC bands.
Author: David Shupe, IRSA Scientist, and the IRSA Science Team
Updated On: 2022-02-14
Contact: irsasupport@ipac.caltech.edu or https://jira.ipac.caltech.edu/irsasupport
If you use astropy for published research, please cite the authors. Follow these links for more information about citing astropy:
If you use SEIP data in published research, please cite the dataset Digital Object Identifier (DOI): 10.26131/IRSA433.