Two Cool Galaxies: M81 and M82

How many details can you see when you take a look at galaxies M81 and M82?

On October 13, 2015, Contributing Editor Howard Banich experienced a spectacular morning of observing at Steens Mountain in southeastern Oregon. With fantastic transparency and increasingly good seeing, he was able to view M82 as he'd never seen it before. His view of M81 wasn't too shabby, either! Howard shared the story of that morning's observing in our May 2016 issue. Here, he shares the full details of his targets, M81 and M82, to assist you in your observations of these "two cool galaxies." (This list is also available as a downloadable .pdf.) At the bottom of this page, you can also find links to further reading on the the subject.

M82 Details — Partial List
(Sources: Aladin, NED, and Simbad. Regions defined by O’Connell & Mangano, 1978)

M82 — one cool galaxy.

Annotated sketch of M82. Sections detailed here: Regions A, B, C, D, and E, and Source B-21. Click on image to make larger.
Howard Banich

Region A
Star Cluster: MGG 1c
Star Cluster: [SWG2006] A1
Star Cluster: MGG 1b
Radio source: [MMW2002] 44.93+63.9
Radio source: [FMB2008] 45.17+61.2
Radio source: [FMB2008] 44.89+61.2
Radio source: [RVZ2004] 44.84+61.8
X-ray source: CXOM82 J095553.4+694047
SNR: [HTC94] 39
SNR: [MMW2002] 44.91+61.1
SNR: [MPW94] 44.91+61.1
SNR: [MPW94] 44.43+61.8
? SNR: [HTC94] 38
? SNR: [HTC94] 35
Molecular Cloud: [KHL2005] C

Region C
Star cluster: MGG 3
Star cluster: MGG m
Star cluster: MGG k
SNR: [HTC94] 37
Radio source: [FMB2008] 44.51+58.2
Radio source: [FMB2008] 44.28+59.3
Radio source: [FMB2008] 44.01+59.6
Radio source: EQ J095552.5+694045.4
HMXB: CXOU J095552.7+694045*
X-ray source: [WSG84] 7
X-ray source: CXOM82 J095552.8+694046
X-ray source: CXOU J095552.7+694046
Maser: [SFF97] 4
*(HMXB =High Mass X-ray Binary)

Region D
Star Cluster: [KBS2008] 78.2
Star Cluster: MGG q
Star cluster:
? SNR: [HTC94] 36
? SNR: [RVZ2004] 44.11+64.3
Radio source: [RVZ2004] 44.50+65.3
Radio source: [RVZ2004] 44.17+64.4
IR source: [GIB2011] 19
HMXB: CXOU J095553.0+694048

Region E
Star cluster: [KBS2008] 67.4
Radio source: [MPW94] 43.51+63.3
Radio source: [RVZ2004] 43.39+62.6
Radio source: [FMB2008] 43.40+62.6
IR source: [GIB2011] 15
IR source: [GIB2011] 14

Source B2-1:
Star Cluster: [SWG2006] B2-1
HMXB: [SST2011] J095554.56+694100.4
X-ray source: 2MASSi J0955547+694100
Radio source: [RVZ2004] 45.93+74.3

M81 Details — Partial List
(Sources: Aladin, NED, and Simbad. Regions labeled by H. Banich)

M81 — cool, too.

Annotated sketch of M81. Sections detailed here: AGN, Regions A, B, C, D, E, F, and G, and Holmberg IX. Click on image to make larger.
Howard Banich.

X-ray source: CXO J095532.0+690354
X-ray source: CXO J095532.6+690353
X-ray source: CXO J095533.1+690355
X-ray source: CXO J095533.14+690355.1
X-ray source: CXO J095533.2+690356
X-ray source: CXO J095533.9+690353
X-ray source: [SPZ2011] ML1
X-ray source: [SPZ2011] ML3
X-ray source: [SPZ2011] ML6
X-ray source: [SPZ2011] 264
UV excess source: [MKH2012] CLU161

Region A
HII: PSK 311
HII: HK NGC 3031 268
HII: [PR95] 50152
HII: [NHM2010] 1588
HII: [NHM2010] 1585
HII: [NHM2010] 1591
UV excess source: [MKH2012] CLU246
SNR: [KBK87] 181
MW Star: Pul -3 630067

Region B
HII: PSK 287
HII: [NHM2010] 1475
HII: [PR95] 50179
HII: [HK83] 305

Region C
HII: [HK83] 343
HII: [NHM2010] 1370
HII: HK NGC 3031 343
HII: [NHM2010] 1365
HII: PSK 266
HII: [KBK87] 266
Association of Stars: [I92b] 78

Region D
HII: [NHM2010] 2160
HII: PSK 416
HII: PSK 422
SNR: [KBK87] 198
MW star: 2MASS J09561763+6906051

Region E
Star Cluster: SDSSJ095521.86+690637.7
Globular Cluster: [PR95] 50777
Star Cluster: SDSS J095521.86+690637.7
? Planetary Nebula: [MPC2001] 44
X-ray source: 2XMM J095521.7+690636
X-ray source: [IW2001] H16
X-ray source: CXO J095521.5+690639

Region F
? Globular Cluster: [PR95] 50804
MW star: [GBT92] 26
Star Cluster: [CFT2001] 045

Region G
HII: [NHM2010] 0454
UV excess source: [MKH2012] CLU036

Holmberg IX – Dwarf Irregular Galaxy
Star cluster: [SPM2005] 3-1322
Star cluster: [SPM2005] 3-1565
Star cluster: [SPM2005] 3-2116
Star cluster: [SPM2005] 3-2376
Star cluster: [SPM2005] 3-2409
? Globular cluster: [SPM2005] HoIX-3-1565
? Globular cluster: [SPM2005] HoIX-3-1322
? Globular cluster: [SPM2005] HoIX-3-2116
? Globular cluster: [SPM2005] HoIX-3-2409
HII: [CVL2009] UGC 5336-12
HII: SDSS J095730.41+690248.7
HII: [MH94a] Ho IX 2
HII: [AIS2009] 18
HII: [MH94a] Ho IX 1
HII: [AIS2009] 17
HII: [MH94a] Ho IX 3
HII: [MH94a] Ho IX 4

Further Reading
Barker, S., R. de Grijs, and M. Cerviño. "Star cluster versus field star formation in the nucleus of the prototype starburst galaxy M 82." Astronomy & Astrophysics 484, no. 3 (June 2008): pp. 711-720.;

de Grijs, Richard. "Star formation timescales in M82." Astronomy and Geophysics 42, no. 4 (2001): pp. 4.12-4.18.;

Devereux, Nick, Holland Ford, Zlatan Tsvetanov, and George Jacoby. "STIS Spectroscopy of the Central 10 Parsecs of M81: Evidence for a Massive Black Hole." Astronomical Journal (2003).

O'Connell, R. W. and J. J. Mangano. "The Central Regions of M82." Astrophysical Journal 221: 62-79 (1978), pp. 62-65.

Patterson, Maria T., Rene A.M. Walterbos, Robert C. Kennicutt, Cristina Chiappini, and David A. Thilker. "An Oxygen Abundance Gradient into the Outer Disk of M81." Monthly Notices of the Royal Astronomical Society 422, No. 1 (2012), pp. 401-419.