This module can be used to query the Simbad service. Presented below are examples that illustrate the different types of queries that can be formulated. If successful all the queries will return the results in a Table.
This is useful if you want to query a known identifier. For instance to query the messier object m1:
>>> from astroquery.simbad import Simbad
>>> result_table = Simbad.query_object("m1")
>>> print(result_table)
MAIN_ID RA DEC RA_PREC DEC_PREC COO_ERR_MAJA COO_ERR_MINA COO_ERR_ANGLE COO_QUAL COO_WAVELENGTH COO_BIBCODE
------- ----------- ----------- ------- -------- ------------ ------------ ------------- -------- -------------- -------------------
M 1 05 34 31.94 +22 00 52.2 6 6 nan nan 0 C R 2011A&A...533A..10L
Wildcards are supported. So for instance to query messier objects from 1 through 9:
>>> from astroquery.simbad import Simbad
>>> result_table = Simbad.query_object("m [1-9]", wildcard=True)
>>> print(result_table)
MAIN_ID RA DEC RA_PREC DEC_PREC COO_ERR_MAJA COO_ERR_MINA COO_ERR_ANGLE COO_QUAL COO_WAVELENGTH COO_BIBCODE
------- ----------- ----------- ------- -------- ------------ ------------ ------------- -------- -------------- -------------------
M 1 05 34 31.94 +22 00 52.2 6 6 nan nan 0 C R 2011A&A...533A..10L
M 2 21 33 27.02 -00 49 23.7 6 6 100.000 100.000 0 C O 2010AJ....140.1830G
M 3 13 42 11.62 +28 22 38.2 6 6 200.000 200.000 0 C O 2010AJ....140.1830G
M 4 16 23 35.22 -26 31 32.7 6 6 400.000 400.000 0 C O 2010AJ....140.1830G
M 5 15 18 33.22 +02 04 51.7 6 6 nan nan 0 C O 2010AJ....140.1830G
M 6 17 40 20 -32 15.2 4 4 nan nan 0 E O 2009MNRAS.399.2146W
M 7 17 53 51 -34 47.6 4 4 nan nan 0 E O 2009MNRAS.399.2146W
M 8 18 03 37 -24 23.2 4 4 18000.000 18000.000 179 E
M 9 17 19 11.78 -18 30 58.5 6 6 nan nan 0 D 2002MNRAS.332..441F
Wildcards are supported by other queries as well - where this is the case, examples are presented to this end. The wildcards that are supported and their usage across all these queries is the same. To see the available wildcards and their functions:
>>> from astroquery.simbad import Simbad
>>> Simbad.list_wildcards()
* : Any string of characters (including an empty one)
[^0-9] : Any (one) character not in the list.
? : Any character (exactly one character)
[abc] : Exactly one character taken in the list. Can also be defined by a range of characters: [A-Z]
Queries that support a cone search with a specified radius - around an identifier or given coordinates are also supported. If an identifier is used then it will be resolved to coordinates using online name resolving services available in Astropy.
>>> from astroquery.simbad import Simbad
>>> result_table = Simbad.query_region("m81")
>>> print(result_table)
MAIN_ID RA DEC RA_PREC DEC_PREC ... COO_ERR_ANGLE COO_QUAL COO_WAVELENGTH COO_BIBCODE
-------------------------- ------------- ------------- ------- -------- ... ------------- -------- -------------- -------------------
[VV2006c] J095534.0+043546 09 55 33.9854 +04 35 46.438 8 8 ... 0 B O 2009A&A...505..385A
...
When no radius is specified, the radius defaults to 20 arcmin. A radius may also be explicitly specified - it can be entered either as a string that is acceptable by Angle or by using the Quantity object:
>>> from astroquery.simbad import Simbad
>>> import astropy.units as u
>>> result_table = Simbad.query_region("m81", radius=0.1 * u.deg)
>>> # another way to specify the radius.
>>> result_table = Simbad.query_region("m81", radius='0d6m0s')
>>> print(result_table)
MAIN_ID RA ... COO_BIBCODE
----------------------- ------------- ... -------------------
M 81 09 55 33.1730 ... 2004AJ....127.3587F
[SPZ2011] ML2 09 55 32.97 ... 2011ApJ...735...26S
[F88] X-5 09 55 33.32 ... 2001ApJ...554..202I
[SPZ2011] 264 09 55 32.618 ... 2011ApJ...735...26S
[SPZ2011] ML1 09 55 33.10 ... 2011ApJ...735...26S
[SPZ2011] ML3 09 55 33.99 ... 2011ApJ...735...26S
[SPZ2011] ML5 09 55 33.39 ... 2011ApJ...735...26S
[SPZ2011] ML6 09 55 32.47 ... 2011ApJ...735...26S
... ... ... ...
[MPC2001] 8 09 54 45.50 ... 2001A&A...379...90M
2MASS J09561112+6859003 09 56 11.13 ... 2003yCat.2246....0C
[PR95] 50721 09 56 36.460 ...
PSK 72 09 54 54.1 ...
PSK 353 09 56 03.7 ...
[BBC91] S02S 09 56 07.1 ...
PSK 489 09 56 36.55 ... 2003AJ....126.1286L
PSK 7 09 54 37.0 ...
If coordinates are used, then they should be entered using an astropy.coordinates object. Limited support for entering the coordinates directly as a string also exists - only for ICRS coordinates (though these may just as well be specified by the ICRS object)
>>> from astroquery.simbad import Simbad
>>> import astropy.coordinates as coord
>>> # works only for ICRS coordinates:
>>> result_table = Simbad.query_region("05h35m17.3s -05h23m28s", radius='1d0m0s')
>>> print(result_table)
MAIN_ID RA ... COO_BIBCODE
----------------------- ------------- ... -------------------
HD 38875 05 34 59.7297 ... 2007A&A...474..653V
TYC 9390-799-1 05 33 58.2222 ... 1998A&A...335L..65H
TYC 9390-646-1 05 35 02.830 ... 2000A&A...355L..27H
TYC 9390-629-1 05 35 20.419 ... 2000A&A...355L..27H
TYC 9390-857-1 05 30 58.989 ... 2000A&A...355L..27H
TYC 9390-1171-1 05 37 35.9623 ... 1998A&A...335L..65H
TYC 9390-654-1 05 35 27.395 ... 2000A&A...355L..27H
TYC 9390-656-1 05 30 43.665 ... 2000A&A...355L..27H
... ... ... ...
TYC 9373-779-1 05 11 57.788 ... 2000A&A...355L..27H
TYC 9377-513-1 05 10 43.0669 ... 1998A&A...335L..65H
TYC 9386-135-1 05 28 24.988 ... 2000A&A...355L..27H
TYC 9390-1786-1 05 56 34.801 ... 2000A&A...355L..27H
2MASS J05493730-8141270 05 49 37.30 ... 2003yCat.2246....0C
TYC 9390-157-1 05 35 55.233 ... 2000A&A...355L..27H
PKS J0557-8122 05 57 26.80 ... 2003MNRAS.342.1117M
PKS 0602-813 05 57 30.7 ...
For other coordinate systems, use the appropriate astropy.coordinates object:
>>> from astroquery.simbad import Simbad
>>> import astropy.coordinates as coord
>>> import astropy.units as u
>>> result_table = Simbad.query_region(coord.SkyCoord(31.0087, 14.0627,
... unit=(u.deg, u.deg), frame='galactic'),
... radius='0d0m2s')
>>> print(result_table)
MAIN_ID RA ... COO_WAVELENGTH COO_BIBCODE
------------------- ------------- ... -------------- -------------------
NAME Barnard's star 17 57 48.4980 ... O 2007A&A...474..653V
Two other options can also be specified - the epoch and the equinox. If these are not explicitly mentioned, then the epoch defaults to J2000 and the equinox to 2000.0. So here is a query with all the options utilized:
>>> from astroquery.simbad import Simbad
>>> import astropy.coordinates as coord
>>> import astropy.units as u
>>> result_table = Simbad.query_region(coord.FK5(ra=11.70, dec=10.90,
... unit=(u.deg, u.deg)),
... radius=0.5 * u.degree,
... epoch='B1950',
... equinox=1950)
>>> print(result_table)
MAIN_ID RA ... COO_BIBCODE
----------------------- ------------- ... -------------------
PHL 6696 00 49.4 ...
BD+10 97 00 49 25.4553 ... 2007A&A...474..653V
TYC 607-238-1 00 48 53.302 ... 2000A&A...355L..27H
PHL 2998 00 49.3 ...
2MASS J00492121+1121094 00 49 21.219 ... 2003yCat.2246....0C
TYC 607-1135-1 00 48 46.5838 ... 1998A&A...335L..65H
2MASX J00495215+1118527 00 49 52.154 ... 2006AJ....131.1163S
BD+10 98 00 50 03.4124 ... 1998A&A...335L..65H
... ... ... ...
TYC 607-971-1 00 47 38.0430 ... 1998A&A...335L..65H
TYC 607-793-1 00 50 35.545 ... 2000A&A...355L..27H
USNO-A2.0 0975-00169117 00 47 55.351 ... 2007ApJ...664...53A
TYC 607-950-1 00 50 51.875 ... 2000A&A...355L..27H
BD+10 100 00 51 15.0789 ... 1998A&A...335L..65H
TYC 608-60-1 00 51 13.314 ... 2000A&A...355L..27H
TYC 608-432-1 00 51 05.289 ... 2000A&A...355L..27H
TYC 607-418-1 00 49 09.636 ... 2000A&A...355L..27H
Queries can also be formulated to return all the objects from a catalogue. For instance to query the ESO catalog:
>>> from astroquery.simbad import Simbad
>>> limitedSimbad = Simbad()
>>> limitedSimbad.ROW_LIMIT = 6
>>> result_table = limitedSimbad.query_catalog('eso')
>>> print(result_table)
MAIN_ID RA ... COO_WAVELENGTH COO_BIBCODE
----------------------- ------------ ... -------------- -------------------
2MASS J08300740-4325465 08 30 07.41 ... I 2003yCat.2246....0C
NGC 2573 01 41 35.091 ... I 2006AJ....131.1163S
ESO 1-2 05 04 36.8 ... 1982ESO...C......0L
ESO 1-3 05 22 36.509 ... I 2006AJ....131.1163S
ESO 1-4 07 49 28.813 ... I 2006AJ....131.1163S
ESO 1-5 08 53 05.006 ... I 2006AJ....131.1163S
This retrieves the reference corresponding to a bibcode.
>>> from astroquery.simbad import Simbad
>>> result_table = Simbad.query_bibcode('2005A&A.430.165F')
>>> print(result_table)
References
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
2005A&A...430..165F -- ?
Astron. Astrophys., 430, 165-186 (2005)
FAMAEY B., JORISSEN A., LURI X., MAYOR M., UDRY S., DEJONGHE H. and TURON C.
Local kinematics of K and M giants from CORAVEL/Hipparcos/Tycho-2 data. Revisiting the concept of superclusters.
Files: (abstract)
Notes: <Available at CDS: tablea1.dat notes.dat>
Wildcards can be used in these queries as well. So to retrieve all the bibcodes from a given journal in a given year:
>>> from astroquery.simbad import Simbad
>>> result_table = Simbad.query_bibcode('2013A&A*', wildcard=True)
>>> print(result_table)
References
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
2013A&A...549A...1G -- ?
Astron. Astrophys., 549A, 1-1 (2013)
GENTILE M., COURBIN F. and MEYLAN G.
Interpolating point spread function anisotropy.
Files: (abstract) (no object)
2013A&A...549A...2L -- ?
Astron. Astrophys., 549A, 2-2 (2013)
LEE B.-C., HAN I. and PARK M.-G.
Planetary companions orbiting M giants HD 208527 and HD 220074.
Files: (abstract)
2013A&A...549A...3C -- ?
Astron. Astrophys., 549A, 3-3 (2013)
COCCATO L., MORELLI L., PIZZELLA A., CORSINI E.M., BUSON L.M. and DALLA BONTA E.
Spectroscopic evidence of distinct stellar populations in the counter-rotating stellar disks of NGC 3593 and NGC 4550.
Files: (abstract)
2013A&A...549A...4S -- ?
Astron. Astrophys., 549A, 4-4 (2013)
SCHAERER D., DE BARROS S. and SKLIAS P.
Properties of z ~ 3-6 Lyman break galaxies. I. Testing star formation histories and the SFR-mass relation with ALMA and near-IR spectroscopy.
Files: (abstract)
2013A&A...549A...5R -- ?
Astron. Astrophys., 549A, 5-5 (2013)
RYGL K.L.J., WYROWSKI F., SCHULLER F. and MENTEN K.M.
Initial phases of massive star formation in high infrared extinction clouds. II. Infall and onset of star formation.
Files: (abstract)
2013A&A...549A...6K -- ?
Astron. Astrophys., 549A, 6-6 (2013)
KAMINSKI T., SCHMIDT M.R. and MENTEN K.M.
Aluminium oxide in the optical spectrum of VY Canis Majoris.
Files: (abstract)
These queries can be used to retrieve all of the names (identifiers) associated with an object.
>>> from astroquery.simbad import Simbad
>>> result_table = Simbad.query_objectids("Polaris")
>>> print(result_table)
ID
--------------------
ADS 1477 AP
** STF 93A
WDS J02318+8916A
** WRH 39
NAME Lodestar
PLX 299
SBC9 76
* 1 UMi
* alf UMi
AAVSO 0122+88
ADS 1477 A
AG+89 4
BD+88 8
CCDM J02319+8915A
CSI+88 8 1
FK5 907
GC 2243
GCRV 1037
GEN# +1.00008890A
GSC 04628-00237
HD 8890
HIC 11767
HIP 11767
HR 424
IDS 01226+8846 A
IRAS 01490+8901
JP11 498
N30 381
NAME NORTH STAR
NAME POLARIS
PMC 90-93 640
PPM 431
ROT 3491
SAO 308
SBC7 51
SKY# 3738
TD1 835
TYC 4628-237-1
UBV 21589
UBV M 8201
V* alf UMi
PLX 299.00
WDS J02318+8916Aa,Ab
These queries can be used to retrieve all the objects that are contained in the article specified by the bibcode:
>>> from astroquery.simbad import Simbad
>>> result_table = Simbad.query_bibobj('2005A&A.430.165F')
>>> print(result_table)
MAIN_ID RA DEC RA_PREC DEC_PREC COO_ERR_MAJA COO_ERR_MINA COO_ERR_ANGLE COO_QUAL COO_WAVELENGTH COO_BIBCODE
--------- ------------ ------------ ------- -------- ------------ ------------ ------------- -------- -------------- -------------------
NGC 524 01 24 47.707 +09 32 19.65 7 7 nan nan 0 B I 2006AJ....131.1163S
NGC 3593 11 14 37.002 +12 49 04.87 7 7 nan nan 0 B I 2006AJ....131.1163S
NGC 4138 12 09 29.788 +43 41 07.14 7 7 nan nan 0 B I 2006AJ....131.1163S
NGC 4550 12 35 30.612 +12 13 15.44 7 7 nan nan 0 B I 2006AJ....131.1163S
NGC 5179 13 29 30.875 +11 44 44.54 7 7 nan nan 0 B I 2006AJ....131.1163S
NGC 5713 14 40 11.528 -00 17 21.16 7 7 nan nan 0 B I 2006AJ....131.1163S
Anything done in SIMBAD’s criteria interface can be done via astroquery. See that link for details of how these queries are formed.
>>> from astroquery.simbad import Simbad
>>> result = Simbad.query_criteria('region(box, GAL, 0 +0, 3d 1d)', otype='SNR')
>>> print result
MAIN_ID RA DEC RA_PREC DEC_PREC COO_ERR_MAJA COO_ERR_MINA COO_ERR_ANGLE COO_QUAL COO_WAVELENGTH COO_BIBCODE
--------------------- ----------- ----------- ------- -------- ------------ ------------ ------------- -------- -------------- -------------------
EQ J174702.6-282733 17 47 02.6 -28 27 33 5 5 nan nan 0 D 2002ApJ...565.1017S
[L92] 174535.0-280410 17 48 44.4 -28 05 06 5 5 3000.000 3000.000 0 D
[GWC93] 19 17 42 04.9 -30 04 04 5 5 3000.000 3000.000 1 D
SNR G359.1-00.2 17 43 29 -29 45.9 4 4 nan nan 0 E 2000AJ....119..207L
SNR G000.1-00.2 17 48 42.5 -28 09 11 5 5 nan nan 0 D 2008ApJS..177..255L
SNR G359.9-00.9 17 45.8 -29 03 3 3 nan nan 0
SNR G359.4-00.1 17 44 37 -29 27.2 4 4 18000.000 18000.000 1 E
NAME SGR D 17 48 42 -28 01.4 4 4 18000.000 18000.000 0 E
SNR G359.1-00.5 17 45 25 -29 57.9 4 4 18000.000 18000.000 1 E
NAME SGR D SNR 17 48.7 -28 07 3 3 nan nan 0 E
Suzaku J1747-2824 17 47 00 -28 24.5 4 4 nan nan 0 E 2007ApJ...666..934C
SNR G000.4+00.2 17 46 27.65 -28 36 05.6 6 6 300.000 300.000 1 D
SNR G001.4-00.1 17 49 28.1 -27 47 45 5 5 nan nan 0 D 1999ApJ...527..172Y
GAL 000.61+00.01 17 47.0 -28 25 3 3 nan nan 0 D
SNR G000.9+00.1 17 47.3 -28 09 3 3 nan nan 0 E R 2009BASI...37...45G
SNR G000.3+00.0 17 46 14.9 -28 37 15 5 5 3000.000 3000.000 1 D
SNR G001.0-00.1 17 48.5 -28 09 3 3 nan nan 0 E R 2009BASI...37...45G
NAME SGR A EAST 17 45 47 -29 00.2 4 4 18000.000 18000.000 1 E
There may be times when you wish to change the defaults that have been set for the Simbad queries.
To fetch all the rows in the result, the row limit must be set to 0. However for some queries, results are likely to be very large, in such cases it may be best to limit the rows to a smaller number. If you want to do this only for the current python session then:
>>> from astroquery.simbad import Simbad
>>> Simbad.ROW_LIMIT = 15 # now any query fetches at most 15 rows
If you would like to make your choice persistent, then you can do this by modifying the setting in the Astroquery configuration file.
The timeout is the time limit in seconds for estabishing connection with the Simbad server and by default it is set to 100 seconds. You may want to modify this - again you can do this at run-time if you want to adjust it only for the current session. To make it persistent, you must modify the setting in the Astroquery configuration file.
>>> from astroquery.simbad import Simbad
>>> Simbad.TIMEOUT = 60 # sets the timeout to 60s
The VOTable fields that are currently returned in the result are set to main_id and coordinates. However you can specify other fields that you also want to be fetched in the result. To see the list of the fields:
>>> from astroquery.simbad import Simbad
>>> Simbad.list_votable_fields()
col0 col1 col2
----------------- ------------ --------------
dim main_id propermotions
dim_angle measurements ra(opt)
dim_bibcode mesplx ra_prec
dim_incl mespm rot
dim_majaxis mk rv_value
The above shows just a small snippet of the table that is returned and has all the fields sorted lexicographically column-wise. For more information on a particular field:
>>> from astroquery.simbad import Simbad
>>> Simbad.get_field_description('ra_prec')
right ascension precision code (0:1/10deg, ..., 8: 1/1000 arcsec)
To set additional fields to be returned in the VOTable:
>>> from astroquery.simbad import Simbad
>>> customSimbad = Simbad()
# see which fields are currently set
>>> customSimbad.get_votable_fields()
['main_id', 'coordinates']
# To set other fields
>>> customSimbad.add_votable_fields('mk', 'rot', 'bibcodelist(1800-2014)')
>>> customSimbad.get_votable_fields()
['main_id', 'coordinates', 'mk', 'rot', 'bibcodelist(1800-2014')]
You can also remove a field you have set or astroquery.simbad.SimbadClass.reset_votable_fields(). Continuing from the above example:
>>> customSimbad.remove_votable_fields('mk', 'coordinates')
>>> customSimbad.get_votable_fields()
['rot', 'main_id']
# reset back to defaults
>>> customSimbad.reset_votable_fields()
>>> customSimbad.get_votable_fields()
['main_id', 'coordinates']
The SIMBAD query tool creates a script query that returns VOtable XML data that is then parsed into a SimbadResult object. This object then parses the data and returns a table parsed with astropy.io.votable.parse.
SimbadClass() | The class for querying the Simbad web service. |
Conf | Configuration parameters for astroquery.simbad. |