Sky & Deep Sky

28 Major Constellations Named Stars The Nick Strobel's Tutorial Tables

25 Lesser Constellations Southern Sky Messier Tables

1) CARINA 2) CENTAURUS 3) CRUX 4) VELA

CARINA - the Keel (of the Argo) - Car

Angular separation Canopus - Eta Carinae = 35°

Click on a star name for more informations        

Name	Magn.	Dist. (L.Y.)	Temp.°K	C.	Type	Greek	Const.
Canopus	-0.72	74	7.400		F0	Alpha	Car
Miaplacidus	1.68	64	9.360		A2	Beta	Car
Avior	1.86	79	4.440		K3	Epsilon	Car
Aspidiske	2.25	299	7.800		A8	Iota	Car

The Carina Nebula is one of the brightest optical emission nebulae in the Milky Way. It stretches over some 2.5 degrees of sky which, at a distance of 8.000 l.y., is 300 l.y. across, about twenty times the size of the Orion Nebula. Two clusters of young stars are primarly responsible for heating the nebula. Each cluster contains one of the brightest known stars in our galaxy. One is HD93129 A, which has a mass estimated to be 120 times that of the Sun and releases most of its five millions solar luminosities as ultraviolet radiation. The second bright star is Eta Carinae.
Eta Carinae, which also is one of the most luminous stars in our galaxy whith a bolometric or total luminosity exceeding 10 ⁴⁰ erg sec -1, emits most of its energy in the infrared. Eta Carinae is today the brightest infrared source outside our solar system observed at wavelengths of 10 and 20 microns. At about 7th magnitude, Eta Carinae is not visible to the naked eye today, but the star brightness has changed by large amounts over the centuries. Halley estimated it ot be 4 times the magnitude observed in 1977. About one hundred years later it was observed to be two magnitudes brighter. During the 1843 it had brightened to magnitude -1 and was the second brightest star in the sky! Eta Carinae remained brighter than first magnitude until 1857, then faded to magnitude 8 by 1900. However, by the late 1970s, it had brightened to mgnitude 6.2. It continues to show slow changes in its brightness.

Left: the central portion of Eta Carinae Nebula. Right: The "Keyhole" Nebula.

In the small region pictured here are the most luminous stars known in our Galaxy, each brighter than a million sun-like stars. To the bottom left of the picture is Eta Carinae, shrouded in a small bright irregular nebula. In the upper right is a cluster (Trumpler 14) of very young stars which appear to be associated with a number of bright edged "elephant trunk" dust lanes, typical of many star-forming regions.
The other picture shows the "Keyhole" Nebula. This Nebula was first sketched and described by Sir John Herschel in 1838. He noted the circular shell visible in the upper part of the picture extending to the south to form a keyhole-shaped nebula. This southern outline is no longer bright and appears only a dark dust cloud. It seems that, in the years since Herschel's observation, Eta Carinae, to the left of the dust cloud, has buried itself in a cocoon of dust that it ejected, and light from the star is no longer able to illuminate the rim of the "keyhole".

NGC 3603 & 3576.
The apparent intimacy of these two star-forming regions is line-of-sight effect because these two objects are at quite different distances from the Sun. The curious looped nebula NGC 3576 is about 7.000 light years from us while its apparent neighbor NGC 3603 is more than twice as far away. That NGC 3603 is the more distant is confirmed by its color, which is ruddier red than the pinkish hue of NGC 3576. The change in color is due to absorption of the blue-light component of the nebulosity by dust particles in the much longer line of sight. This effect is known as interstellar reddening, when it is actually the blue light that is affected.
NGC 3603 is home to a massive star cluster, thick dust pillars, and a star about to explode. The central open cluster contains about 2000 bright stars, each of which is much brighter and more massive than our Sun. Together, radiations from these stars are energizing and pushing away surrounding material, making NGC 3603 one of the most interesting HII regions known. NGC 3603 is about 20,000 light-years away, and the region shown is about 20 light-years across. Possibly most interesting about this recently released, representative-color picture are the large number of dim stars visible. These stars are less massive than our Sun, demonstrating that great numbers of low-mass stars also form in active starburst regions.

NGC 3293 Open Cluster Magn. 4.7

NGC 3603 - particular

CENTAURUS - the Centaur - Cen

Angular separation Menkent - Lambda Cen = 35°

Click on a star name for more informations         Name Magn. Dist. (L.Y.) Temp.°K C. Type Greek Const. Rigel Kentaurus A -0.01 4.39 5.800   G2 Alpha A Cen Hadar 0.61 320 25.600   B1 Beta Cen Rigel Kentaurus B 1.33 4.39 4.680   K1 Alpha B Cen Menkent 2.06 50 4.800   K0 Theta Cen Muhlifain 2.17 190 9.680   A1 Gamma Cen Proxima 10.7 4.24 2.800   M5 Alpha C ? Cen

If humanity looks for intelligent life elsewhere, then Alpha Centauri is an excellent candidate . . .

	How to find Proxima  from the original  by Doug Brown

With a magnitude of 10.7, Proxima Centauri is exceptional for one reason, it is the nearest star to the Solar System. At about 4.24 light years, Proxima Centauri is marginally closer than the easily identifiable and bright star Alpha Centauri. In space, both stars are separated by about one sixth of a light year. The question as to whether Proxima Centauri is gravitationally linked to the famous double star system of Alpha Centauri is not yet fully resolved. Only after being interested in astronomy for several years did I get around to looking for Proxima Centauri. When I did however, I found it more difficult than I had thought. To make matters worse, I was unsure whether I had actually observed Proxima Centauri or just some other nearby look-alike reddish/orange star.
Proxima is a well known variable flare star and has been described by Robert Burnham in his Celestial Handbook as possibly one of the most active stars known of its type. Flare stars are usually dim red dwarfs which for some reason, increase and decrease their brightness over a matter of minutes.
As Proxima Centauri is intrinsically around 13,000 times less luminescent than the Sun, any increase in brightness over a short period can often be readily observed. Proxima Centauri has a diameter around 64,000 kilometres or about five times the size of the earth, hence it is a very small star when compared to the Sun. Its a bit like comparing a pea with a large rock melon. To put this into some context, it must be remembered that the Sun itself is considered a dwarf star on the stellar scale.

Using the Charts
The two pictures shown here differ in both their scale and limiting stellar magnitudes. Picture A shows Alpha and Beta Centauri (pointers to the Southern Cross) and Alpha Circinus. The latter is a bright naked eye star about four degrees from Alpha Centauri in the direction of the South Celestial Pole. Also, Alpha Circinus forms an easily identifiable right angle triangle with the other two stars. Note the asterism shaped like a broken cross marked on the chart.
Picture B is a more detailed map of the immediate region of Proxima Centauri. It should provide enough background stars for the observer to zero in on Proxima Centauri.
To locate Proxima Centauri, I suggest that you first find the cross shaped asterism using Picture A. This should not be too difficult. Now with the help of Picture B, in the direction of Alpha Circinus look for a reddish/orange star about half a degree from the asterism (the diameter of the Moon). Depending on the instrument you are using, Proxima Centauri and the asterism might be in the same field of view. If not, you will need to move your instrument a small amount in a direction towards Alpha Circini.

	Particular of the central region
	Centaurus A - NGC 5128 Spiral Galaxy - Magn. 8.0 Dist. 16 mill. l.y.

The peculiar radio galaxy Centaurus A (NGC 5128) provides a striking example of how dust can affect our view of a galaxy, and how going to redder wavelengths helps penetrate interstellar dust. This image shows at once the reddening effects of dust in the strong dust lane, some red emission from ionized gas, and blue regions of star formation along the dust lane. The dust blocks most of the light in the blue, and progressively less going through the other wavelengths (and new images deeper in the infrared show even less of the dust). This effect against stars in our own galaxy is known as interstellar reddening, though the effect in galaxies is complicated by the fact that some of the light is not in fact absorbed but scattered in different directions upon encountering a dust grain. Centaurus A is an unusually colorful galaxy; note the very blue star clusters along the edges of the dust lane. This is widely held to be an elliptical galaxy that has acquired a spiral by merger, with the broad and gas-rich dust lane being the most visible debris of the collision. Cen A is also a very strong source of radio emission.

Omega Centauri - NGC 5139
Globular Cluster - Magn. 3.7 - Dist. 17.000 l.y.
Pictured left is the largest ball of stars in our Galaxy. About 10 million stars orbit the center of this globular cluster - named Omega Centauri - as this giant globular cluster orbits the center of our Galaxy. Recent evidence indicates that Omega Centauri is by far the most massive of the about 160 globular clusters in the Milky Way. The stars in globular clusters are generally older, redder and less massive than our Sun. Studying globular clusters tells us about the history of our Galaxy and the age of the universe.

Lambda Centauri Open Cluster
Magn. 4.5 - Dist. 6.800 l.y.

CRUX - the Cross - Cru

Angular separation Acrux - Gacrux = 6°

Click on a star name for more informations         Name Magn. Dist. (L.Y.) Temp.°K C. Type Greek Const. Mimosa 1.25 460 28.000   B0 Beta Cru Acrux 1.33 510 28.000   B0 Alpha Cru Gacrux 1.63 88 3040   M3 Gamma Cru

VELA - the Sails (of the Argo) - Vel

Angular separation Suhail al Muhlif - Mu Vel = 26°

The Vela Supernova Remnant. The explosion is over but the consequences continue. About eleven thousand years ago a star in the constellation of Vela exploded, creating a strange point of light briefly visible to humans living near the beginning of recorded history.

Click on a star name for more informations        

Name	Magn.	Dist. (L.Y.)	Temp.°K	C.	Type	Greek	Const.	Ab.
Al Nair	1.74	101	13.600		B7	Alpha	Grus	Gru
Al Dhanab	3.01	230	12.400		B8	Gamma	Grus	Gru
Atria	1.92	105	4.560		K2	Alpha	Triangulum Aus.	TrA
Peacock	1.94	180	23.200		B2	Alpha	Pavo	Pav
Kakkab	2.30	580	25.600		B1	Alpha	Lupus	Lup
Ankaa	2.39	62	4.800		K0	Alpha	Phoenix	Phe
Persian	3.11	101	4.800		K0	Alpha	Indus	Ind
Alfecca Mer.	4.11	130	9.360		A2	Alpha	Corona Aus.	CrA
Polaris Australe	5.47	-	7.400		F0	Sigma	Octans	Oct

Constellation pictures are modified screen displaies of Voyager II™ version 2.0 for the Macintosh™, the Astronomy Program of Carina Software, 12919 Alcosta Blvd Suite #7, San Ramon, CA 94583

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