Lyons Groups of Galaxies

{{Short description|Astronomical catalogue}}

Lyons Groups of Galaxies (or LGG) is an astronomical catalog of nearby groups of galaxies complete to a limiting apparent magnitude B0=14.0 with a recession velocity smaller than 5,500 km/s. The catalogue was obtained from the Lyon-Meudon Extragalactic Database. Two methods were used in group construction: a percolation method derived from Huchra and Geller {{cite journal

| last1 = Huchra

| first1 = J. P.

| last2 = Geller

| first2 = M. J.

|date=June 1982

| title = Groups of galaxies. I - Nearby groups

| journal = Astrophysical Journal

| series = Part 1

| volume = 257

| issue = June 15, 1982

| pages = 423–437

| bibcode = 1982ApJ...257..423H

| doi = 10.1086/160000

| accessdate = March 24, 2012

| url = http://articles.adsabs.harvard.edu/cgi-bin/nph-iarticle_query?1982ApJ...257..423H&data_type=PDF_HIGH&whole_paper=YES&type=PRINTER&filetype=.pdf

}} and a hierarchical method initiated by R. Brent Tully.{{cite journal

| last1 = Tully

| first1 = R. B.

| authorlink1 = R. B. Tully

|date=April 1980

| title = Nearby groups of galaxies. I - The NGC 1023 group

| journal = Astrophysical Journal

| series = Part 1

| volume = 237

| issue = Apr. 15, 1980

| pages = 390–403

| bibcode = 1980ApJ...237..390T

| doi = 10.1086/157881

| accessdate = March 24, 2012

| url = http://articles.adsabs.harvard.edu/cgi-bin/nph-iarticle_query?1980ApJ...237..390T&data_type=PDF_HIGH&whole_paper=YES&type=PRINTER&filetype=.pdf

}} The catalog is a synthesized version of the two results.

The LGG includes 485 groups and 3,933 member galaxies.