Object of the Week February 12th, 2017- Grand Design Spiral NGC2997

NGC2997
UGCA181
PGC27978

Antlia

Galaxy

RA 09 45 39
DEC -31 11 23

Mag 10.2

Size 9.2' x 7.4'

Class SAB(rs)c

Antlia the Air Pump is a small nondescript constellation in the southern hemisphere just beneath Crater and Hydra. Originally coined Antlia Pneumatica in 1763- giving recognition to the recently invented pneumatic air pump - the name was shortened to just Antlia by John Herschel in 1844. A rather 'boring' area of the sky visually, the constellation is comprised of just 4 stars approximately 4th magnitude with the rest being even dimmer. Absent of any proper Milky Way objects, Antlia does house a beautiful grand design spiral that tends to be missed by many deepsky observers.

Using his 18.7" f/13 speculum mirrored telescope, Sir William Herschel discovered NGC2997 on March 4th, 1793. Both large and faint, NGC2997 is a nearly face on spiral armed galaxy with a bright core. Tilted away from us at approximately 50°, it isn't as face on as M51 but it still provides us a beautiful view of its arms all the while giving the galaxy a bit of an elliptical shape to it.

Sadly, NGC2997 isn't visible from my 40° latitude. But I was fortunate enough to observe it on February 24th, 2009 from Ft Davis Texas using Jimis 48". Recognizing I was being spoiled considering the telescope, the view was just astounding. Using a 13mm Ethos at 375x the galaxy filled the view. My notes read "Damn nice! Very M51 like. Very apparent arms. 2 arms on N side, single arm on the other twisting CCW. Bright core. HII regions throughout" Sadly, this was my first and only view of this galaxy. Having been observing in Australia twice (in march/april no less) since my observation in 2009, I have yet to observe this galaxy from the southern hemisphere. One day I will.

Online notes reveal that scopes as small as 5" can see NGC2997s glow. Stephen O'Meara in Southern Gems wrote "Very beautiful, bright ellipse of light about 5' across with a starlike core" while using his 5" refractor. So those with smaller scopes need not be intimated.

One bit of uncertainty I found while researching this object was its distance. Though the consensus appears to be that NGC2997 lies approximately 25 million light years away, I found reports indicating distances at 55Mly away as well as one at the European Space Agency placing it at 140Mly away!

Nevertheless, if you have the opportunity to observe under southern skies this spring (or autumn depending on where you live) be sure to point your scope towards a rather blank piece of real estate named Antlia. There you will find one of the skies grandest spiral galaxys either hemisphere has to offer, NGC2997. Enjoy.

And as always,


"Give it a go and let us know!
Good luck and great viewing!"

NGC2997_AAO.jpg
©AAO

ngc2997capella.jpg
©capella observatory

ngc2997esoIR.jpg
©ESO