Martin Krzywinski / Canada's Michael Smith Genome Sciences Centre / mkweb.bcgsc.ca Martin Krzywinski / Canada's Michael Smith Genome Sciences Centre / mkweb.bcgsc.ca - contact me Martin Krzywinski / Canada's Michael Smith Genome Sciences Centre / mkweb.bcgsc.ca on Twitter Martin Krzywinski / Canada's Michael Smith Genome Sciences Centre / mkweb.bcgsc.ca - Lumondo Photography Martin Krzywinski / Canada's Michael Smith Genome Sciences Centre / mkweb.bcgsc.ca - Pi Art Martin Krzywinski / Canada's Michael Smith Genome Sciences Centre / mkweb.bcgsc.ca - Hilbertonians - Creatures on the Hilbert CurveMartin Krzywinski / Canada's Michael Smith Genome Sciences Centre / mkweb.bcgsc.ca - Pi Day 2020 - Piku
Trance opera—Spente le Stellebe dramaticmore quotes

space + pixels

places to go
nobody to see
If you like space, you'll love my the 12,000 billion light-year map of clusters, superclusters and voids. Find the biggest nothings in Boötes and Eridanus.
And the seven stars go squawking
like geese about the sky

The Sky, northern hemisphere

The mysterious and incomplete sky is yours in these 100 megapixel and 10 gigapixel maps of the northern celestrial hemisphere.

Included are about 2.4 million stars from the major catalogues (HR, Hipparcos and Tycho-2). In the 10 gigapixel image, the entire 100+ million star UCAC4 catalogue is included. Canonical IAU constellation asterisms are included. About 100,000 deep sky objects are also shown. These are jittered to avoid overlap, which is why some clusters of objects appear as large globules of symbols.

In the 10 gigapixel map, labels are lovingly placed and formatted to include name, catalogue and magnitude data. The 100 megapixel map has no labels.

Stellar and deepsky object annotations taken from Vizier.

Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
Icons for celestial objects.

The northern and southern hemisphere maps sample from the following lists

        313 canonical star names approved by the IAU (2017-11-19)
      4,009 NASA exoplanet archive exoplanets (4 July 2019)
    162,252 deep-sky objects (not stars or solar system objects)
  2,508,427 stars from Yale Bright Star (HR), Hipparcos-2 HIP and Tycho-2 catalgoues
111,235,172 stars from USNO CCD Astrograph Catalog (v4) (UCAC4) catalogue (down to magnitude 16.593)

The maps are shown in azimuthal projection and comprise two layers. The top layer contains stars at magnitude < 13 (these are shown with shapes larger than a single pixel), deep-sky objects and exoplanets. All objects on this layer have a 1-pixel black stroke to make them stand out from the layer below, which contains stars at magnitude ≥ 13 (shown as single pixels).

Star shapes are not jittered. Deep-sky object shapes are jittered to avoid overlap with adjacent shapes. All deep-sky objects are drawn by priority (e.g. those that have labels are drawn first and then by magnitude) and if a location could not be found within a fixed distance of its position then the shape is not drawn. This is why the number of objects on the map is lower (161,952) than in the list (162,252).

To maximize room for objects, the 100 megapixel maps are without labels and do not show stars with magnitude > 13. The 10 gigapixel have labels generated by sketchy heuristics (read below) and include all stars.

northern hemisphere

    74,121 deep-sky objects (13,426 with labels)
     3,059 exoplanets (all labeled)
 1,274,250 stars (mag < 13) (231,048 with labels)
43,008,972 stars (mag ≥ 13)

southern hemisphere

    87,831 deep-sky objects (9,120 with labels)
       950 exoplanets (all labeled)
 1,489,112 stars (mag < 13) (332,973 with labels)
67,971,985 stars (mag ≥ 13)

stars

labels

Labels for stars include the IAU name, other common names and constellation membership (Greek and numerical index). If these fields are not available, then the star's catalogue entry (e.g. HR, HIP, HD, PPM, SAO, Renson (REN), ADS) is shown. Tycho-2 and UCAC4 names are not shown.

Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
Polaris, also known as the North Star, Lodestar and αUmi1.

Below are some examples of different label formats for stars.

# ; indicates a line break
Alpheratz;Sirrah;αAnd21
Dubhe;αUMa50
La Superba
HD343127/45
RST 5162/AB
BRT 2512/AB
COU 1209/AB
STF 1929/AB
ADS15211 AB
HIP116228
ιCas
Peg2

magnitude distribution

Shape of distribution shows sqrt-transformed values.

              -1.0000>         2  0.000
   -1.0000     0.0000          3  0.000  0.000                                                   
    0.0000     1.0000         12  0.000  0.000                                                   
    1.0000     2.0000         34  0.000  0.000                                                   
    2.0000     3.0000        131  0.000  0.000                                                   
    3.0000     4.0000        357  0.000  0.000                                                   
    4.0000     5.0000       1124  0.000  0.000                                                   
    5.0000     6.0000       3471  0.000  0.000                                                   
    6.0000     7.0000      10415  0.000  0.000                                                   
    7.0000     8.0000      29444  0.000  0.000 *                                                 
    8.0000     9.0000      83296  0.001  0.001 **                                                
    9.0000    10.0000     222021  0.002  0.003 ***                                               
   10.0000    11.0000     604511  0.005  0.008 ******                                            
   11.0000    12.0000    1756153  0.015  0.024 **********                                        
   12.0000    13.0000    4081779  0.036  0.060 ***************                                   
   13.0000    14.0000    8954480  0.079  0.139 ***********************                           
   14.0000    15.0000   19658992  0.173  0.312 ***********************************               
   15.0000    16.0000   40078420  0.353  0.665 **************************************************
   16.0000    17.0000   38096284  0.335  1.000 ************************************************  
   17.0000    18.0000         31  0.000  1.000                                                   
   18.0000    19.0000         17  0.000  1.000                                                   
   19.0000    20.0000          9  0.000  1.000                                                   
   20.0000    21.0000          5  0.000  1.000                                                   
   21.0000    22.0000          2  0.000  1.000                                                   
   22.0000    23.0000          3  0.000  1.000                                                   
   23.0000    24.0000          2  0.000  1.000                                                   
   24.0000    25.0000          2  0.000  1.000                                                   
              24.8500<     0  0.000
       n    113581000
 average     15.25766
     min     -1.46000
     max     24.85000

Here is a sample SIMBAD TAP query that lists all stars in HR, HIP and TYC catalogues as well as stars that have names.

select oid,ra,dec,allfluxes.v,otype_txt,otypedef.otype_longname,ids.ids
from basic
join ids on ids.oidref = oid
join ident on ident.oidref = oid
join otypedef on otypedef.otype = basic.otype
join allfluxes on allfluxes.oidref = oid
WHERE 
   ident.id like 'TYC %' or 
   ident.id like 'HIP %' or 
   ident.id like 'HR %'  or 
  (ident.id like 'NAME %' and 
   otype_txt not in ('SBG','SFR','As*','Cl*','C?*') and 
   (otypedef.otype_longname like '%star%' or otypedef.otype_longname like '%Star%')
  )

deep-sky objects

labels

Determining the label of an object is done by a series of heuristics. Some labels span more than one line. Labels are jittered to avoid overlap with shapes, where possible.

There is no single right way to label an object, though there are some ways that are more wrong than others. An object can have a large number of identifiers and cobbling a name from these is a fun exercise. For example, consider the magnitude 13.87 Syefert Galaxy known as the Sculptor Filament. This object has the following identifiers.

1ES=0045-25.5
1FGL=J0047.3-2512
1Jy=0045-25|0045-255
1RXS=J004733.3-251722
2E=184|0045.1-2533
2FGL=J0047.0-2516
2MASX=J00473313-2517196
3FGL=J0047.5-2516
6dFGS=gJ004733.1-251719
AGC=20535
AT20G=J004733-251717
Cul=0045-255|0045-25
DUGRS=474-001
ESO=474-29
ESO-LV=474-0290
GLXY=G095.1-88.0+344
HIPASS=J0047-25
INTREF=36
IRAS=00450-2533|F00450-2533
LEDA=2789
MCG=-04-03-009
MRC=0045-255
MSH=00-2-22
NAME=Silver Coin|Sculptor Filament|Scl Filament
NGC=253
NVSS=J004733-251717
OHIO=B -275
PKS=0045-25|J0047-2517|0045-255
PMN=J0047-2517
PSCz=Q00450-2533
RAFGL=5038
RBS=112
RX=J004731-25175|J0047.5-2517
SGC=004507-2533.9
SINGG=HIPASS J0047-25
TeV=J0047-253
UGCA=13
VLSS=J0047.5-2517
WISH=B0045.1-2533
WMAP=62|J0047-2515|J0047-2514|J0047-2513|J0047-2516
[CAB95]=IRAS F00450-2533
[CHM2007]=LDC 26 J004733.13-2517196
[DML87]=570
[M98c]=004505.7-253340
[NKB95]=N0253
[VV2000c]=J004733.2-251717
[VV2003c]=J004733.2-251717
[VV2006c]=J004733.2-251717
[VV2010c]=J004733.2-251717
[VV98c]=J004733.2-251717

Many of the fields can be excluded immediately, such as the [publication reference] ones. Catalogue fields like NAME, M, NGC, IC, LEDA, MLB, NOVA, LSQ, SN, V*, BCLMP are used, taking care of cases where NAME repeats values from other catalogues.

The map shows it as

Sculptor Filament
Silver Coin
NGC253
Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
Sculptor filament, also known as the Silver Coin and NGC253.

Here are some examples of different label formats for deep-sky objects.

# ; indicates a line break
Northern Hubble Deep Field;Hubble Deep Field North
Serpens Triple Radio Source;Serpens SMM1;SH268FIR1
Question Mark Galaxy;Whirlpool Galaxy;M51
Filamentary Nebula;Cirrus Nebula;NGC6960
Solovyov's Object;NOVAAql 1949
SER MOL CLOUD CORE
SN MRK297A;SN1982aa
Cetus Polar Stream
Maia Nebula;NGC1432
NOVAAur 1891/2 4.1
UGC4904V1;SN2006jc
AT2017gay;V*PT And
Watson X1;V*MT Com
SH26235IR Cluster
Nova2006no8in M31
FAUST V023;NGC4276
Giant Void in NGH
NOVAUMi 1956
bn100516014
MLB4-9/3-79
Origem Loop
2Mon Region
Patchick DC
NGC6633 4.6
LEDA2113175
M85OT20061
Orion East
V*V572 And
Teutsch GN
IC131West
DR21(OH)W
Cirrus H1
LDN1551II
IC4414/B
V*SW UMa
SN1990ag
LSQ13zm
SN2015O
NGC937
NGC358
IC1434
M78
IC7

magnitude distribution

Shape of distribution shows sqrt-transformed values.

               0.0000>     2  0.000
    0.0000     1.0000      0  0.000  0.000                                                   
    1.0000     2.0000      2  0.000  0.000 **                                                
    2.0000     3.0000      9  0.001  0.001 ****                                              
    3.0000     4.0000     11  0.001  0.002 ****                                              
    4.0000     5.0000     32  0.003  0.005 ********                                          
    5.0000     6.0000     54  0.005  0.010 **********                                        
    6.0000     7.0000     98  0.009  0.020 **************                                    
    7.0000     8.0000    150  0.014  0.034 *****************                                 
    8.0000     9.0000    196  0.019  0.052 ********************                              
    9.0000    10.0000    228  0.022  0.074 *********************                             
   10.0000    11.0000    360  0.034  0.108 ***************************                       
   11.0000    12.0000    557  0.053  0.161 **********************************                
   12.0000    13.0000    667  0.063  0.224 *************************************             
   13.0000    14.0000    751  0.071  0.296 ***************************************           
   14.0000    15.0000    612  0.058  0.354 ***********************************               
   15.0000    16.0000    565  0.054  0.407 **********************************                
   16.0000    17.0000    861  0.082  0.489 ******************************************        
   17.0000    18.0000   1196  0.113  0.602 **************************************************
   18.0000    19.0000   1070  0.102  0.704 ***********************************************   
   19.0000    20.0000    658  0.062  0.766 *************************************             
   20.0000    21.0000    557  0.053  0.819 **********************************                
   21.0000    22.0000    612  0.058  0.877 ***********************************               
   22.0000    23.0000    473  0.045  0.922 *******************************                   
   23.0000    24.0000    295  0.028  0.950 ************************                          
   24.0000    25.0000    269  0.026  0.976 ***********************                           
   25.0000    26.0000    149  0.014  0.990 *****************                                 
   26.0000    27.0000     61  0.006  0.996 ***********                                       
   27.0000    28.0000     47  0.004  1.000 *********                                         
              28.1600<     0  0.000
       n        10544
 average     16.61758
     min     -4.00000
     max     28.16000

I have selected a representative fraction of known deep-sky objects based on their type and name status. Below is the list of the number of objects of each SIMBAD classification. Because deep-sky objects

      1 *	Hot subdwarf
      1 BLL	BL Lac - type object
      1 ClG	Cluster of Galaxies
      1 EB?	Eclipsing Binary Candidate
      1 FIR	Far-IR source  (\lambda >= 30 {\mu}m)
      1 G?	Possible Galaxy
      1 HH	Herbig-Haro Object
      1 HI	HI (21cm) source
      1 WD*	White Dwarf
      1 WD?	White Dwarf Candidate
      1 XB?	X-ray binary Candidate
      1 ev	transient event
      1 sh	HI shell
      2 *iC	Hot subdwarf
      2 C?*	Possible (open) star cluster
      2 HXB	High Mass X-ray Binary
      2 MGr	Moving Group
      2 Pl	Extra-solar Confirmed Planet
      2 SFR	Star forming region
      2 XB*	X-ray Binary
      3 GrG	Group of Galaxies
      3 Rad	Radio-source
      4 Psr	Pulsar
      4 grv	Gravitational Source
      5 LP?	Long Period Variable candidate
      5 X	X-ray source
      5 mul	Composite object
      6 QSO	Quasar
      7 RS*	Variable of RS CVn type
      9 BNe	Bright Nebula
      9 GNe	Galactic Nebula
      9 cC*	Classical Cepheid (delta Cep type)
     10 BH?	Black Hole Candidate
     10 PoG	Part of a Galaxy
     10 Q?	Possible Quasar
     12 EmO	Emission Object
     13 UV	UV-emission source
     14 Bla	Blazar
     14 bCG	Blue compact Galaxy
     15 St*	Stellar Stream
     17 BY*	Variable of BY Dra type
     18 WU*	Eclipsing binary of W UMa type (contact binary)
     18 bL*	Eclipsing binary of beta Lyr type (semi-detached)
     20 rB	radio Burst
     35 SyG	Seyfert Galaxy
     37 EB*	Eclipsing binary
     39 PaG	Pair of Galaxies
     43 As*	Association of Stars
     43 IR	Infra-Red source
     45 ISM	Interstellar matter
     46 RNe	Reflection Nebula
     48 Y*?	Young Stellar Object Candidate
     59 CGb	Cometary Globule
     60 Al*	Eclipsing binary of Algol type (detached)
     61 LI?	Possible gravitationally lensed image
     74 No?	Nova Candidate
     80 LS?	Possible gravitational lens System
    100 Sy1	Seyfert 1 Galaxy
    121 LeQ	Gravitationally Lensed Image of a Quasar
    126 PN	Planetary Nebula
    127 Le?	Possible gravitational lens
    136 GlC	Globular Cluster
    143 BiC	Brightest galaxy in a Cluster (BCG)
    154 LSB	Low Surface Brightness Galaxy
    191 glb	Globule (low-mass dark cloud)
    219 AGN	Active Galaxy Nucleus
    252 out	Outflow
    269 rG	Radio Galaxy
    299 Cl*	Cluster of Stars
    311 Sy2	Seyfert 2 Galaxy
    361 SB*	Spectroscopic binary
    372 Y*O	Young Stellar Object
    395 GiC	Galaxy in Cluster of Galaxies
    397 reg	Region defined in the sky
    409 IG	Interacting Galaxies
    471 of?	Outflow candidate
    494 OpC	Open (galactic) Cluster
    512 vid	Underdense region of the Universe
    523 gLS	Gravitational Lens System (lens+images)
    535 gLe	Gravitational Lens
    565 GiP	Galaxy in Pair of Galaxies
    590 EmG	Emission-line galaxy
    776 SBG	Starburst Galaxy
    780 DN*	Dwarf Nova
    806 LIN	LINER-type Active Galaxy Nucleus
    842 SR?	SuperNova Remnant Candidate
    979 LeG	Gravitationally Lensed Image of a Galaxy
  1,079 LeI	Gravitationally Lensed Image
  1,080 H2G	HII Galaxy
  1,492 SNR	SuperNova Remnant
  1,850 No*	Nova
  1,963 Cld	Cloud
  2,634 G	Galaxy
  3,144 GiG	Galaxy in Group of Galaxies
  3,149 SN?	SuperNova Candidate
  3,347 PoC	Part of Cloud
  3,389 Mas	Maser
  5,193 bub	Bubble
  5,457 HVC	High-velocity Cloud
  7,206 cor	Dense core
  7,717 MoC	Molecular Cloud
  8,175 gB	gamma-ray Burst
 11,165 SN*	SuperNova
 22,513 ?	Object of unknown nature
 27,800 DNe	Dark Cloud (nebula)
 30,707 HII	HII (ionized) region
 ------
162,252 deep sky objects

Here is a sample SIMBAD TAP query that lists all Messier objects.

select oid,ra,dec,allfluxes.v,sp_type,morph_type,otypedef.otype_shortname,otypedef.otype_longname,ids.ids
from basic
join ids on ids.oidref = oid
join ident on ident.oidref = oid
join otypedef on otypedef.otype = basic.otype
join allfluxes on allfluxes.oidref = oid
WHERE ident.id like 'M %'

All deep-sky objects. This query selects all objects that are not stars.

select oid,ra,dec,allfluxes.v,sp_type,morph_type,otypedef.otype_shortname,otypedef.otype_longname,ids.ids
from basic
join ids on ids.oidref = oid
join ident on ident.oidref = oid
join otypedef on otypedef.otype = basic.otype
join allfluxes on allfluxes.oidref = oid
WHERE 
  otypedef.otype_shortname in ('SBG','SFR','As*','Cl*','C?*') or 
 (otypedef.otype_longname not like '%star%' and otypedef.otype_longname not like '%Star%')