A special star and its surroundings

Eta Carinae
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The star Eta Carinae is a very bright hypergiant with a mass of between 100 and 150 solar masses. It is 4 million times brighter than the Sun, and is 7,500 light-years away from Earth. The giant star’s aggressive ultraviolet radiation illuminates the brightest parts of the nebula named after it. Its strong stellar wind that blows the amount of material equal to Jupiter from the surface of the star each year, shapes the central part of the nebula in its own image. Thus it creates interesting interstellar gas and dust structures rich in shapes and colors, which can be observed from the southern hemisphere in the Carina constellation.

The Eta Carinae hypergiant is not only bright, but sometimes it fakes its own death by erupting or better to say, almost exploding. During this period the restless star radiated 10 percent of the energy of a supernova explosion, and ejected an amount of material equal to 10-12 Suns.

Due to the extremely unfavorable weather in Hungary, I decided to make an “online tour” to Chile, and turn one of the best optics of the Telescope Live robotic telescope network, the 61-cm PlaneWave CDK24 towards this spectacular southern celestial object. From January the 14th to February 1st I collected nearly 2.5 hours of RGB and narrowband material on five nights from the surroundings of the star Eta Carinae. I have already taken a similar remote-controlled picture of this area before, but with a much wider field of view. I got to know the wonderful details of the inner areas of the nebula in more detail during my image processing a few years ago, and I decided to capture them in detail later.


In the last months I experimented a lot with the combination of traditional RGB and narrowband (Ha, SII, OIII) images, so there was no question that I was going to try to capture the surroundings of the Eta Carinae in this way as well. For the aesthetic image processing I used almost the same exposure times per filter, and for setting the colors I mixed the RGB and the narrowband material with the ratio of 50-50%. As a result it is not surprising that I got different colors than usual, which I tried to present in a natural and restrained way.
(text: László Francsics, Lionel Majzik)

Date:

14/01/2021 - 01/02/2021

Total exposure time:

2.4 hours

Location:

Telescope Live - El Sauce Observatory, Río Hurtado, Chile

Camera:

FLI ProLine PL9000

Telescope:

Telescope Live CHI-1: Planewave CDK24 610/3962 mm astrograph

Mount:

Mathis MI-1000/1250

Guiding:

Autoguiding

Focal ratio, length:

f/6.5, 3962 mm

Light:

6 x 300 sec R, 6 x 300 sec G, 5 x 300 sec B, 4 x 300 sec Ha, 4 x 300 sec OIII, 4 x 300 sec SII

Dark:

Pre-calibrated

Dark flat:

Pre-calibrated

Flat:

Pre-calibrated

Bias:

Pre-calibrated

Processing:

Astro Pixel Processor, PixInsight, Adobe Lightroom, Adobe Photoshop

Location

Annotation

Eta Carinae (Robotic)

Main objects: Eta Carinae, Carina Nebula, NGC 3372, Keyhole Nebula

Name:

Carina Nebula, Eta Carinae Nebula, NGC 3372

Constellation:

Carina

Coordinates:

R.A. 10 h 45 m 08 s Dec. -59° 52′ 04″

Type:

Emission Nebula

Distance:

6,500 - 10,000 light-years

Brightness:

1.0m

Apparent size:

2o

Diameter:

230 light-years

Observable: 

Winter and spring (only Southern Hemisphere)

Name:

Eta Carinae, η Carinae, η Car

Constellation:

Carina

Coordinates:

R.A. 10 h 45 m 04 s Dec. -59° 41′ 04″

Type:

Star

Distance:

7,500 light-years

Brightness:

4.3m (variable)