22,30
NGC 3372 Eta Carina Star and Nebula.
I was waxing lyrical to myself at the amazing detail of the Homonculus,just Stunning
But the Southern lobe seemed fainter than I had seen it before,
could have been overwhelmed by the brightness of the star.
the Jets that sort of make up the arms of the (little man) Homonculus could be seen.
The Eta Carina star was the brightest I have ever seen in a telescope, Normally it
Seems to be not quite star like but soft to fuzzy, but this night it was incredibly sharp
Brilliant!
The eyepiece used 6mm Radian plus 9mm TMB which also gave fantastic views.
Hi all,
In February I had the Link Here from which the above quote is derived) moved from the Observation Reports forum to this forum as to encourage feed back on the brightening of the Star Eta Carina, unfortunately none was forth coming
My intrepid Astro buddy Suzy did some investigating and has come up with this Data from AASVO
Thanks Suzy http://www.aavso.org/ql/results?auid...=2455577.93245
The observations in this data for the 25/01/11 corresponds with my observations for that period and the data really proves that sure enough Eta Carina is truly brightening.
Another site worth looking at is http://etacar.fcaglp.unlp.edu.ar/
Which has been presented on other posts on this subject.
I encourage everyone to keep observing Eta Carina as often as possible by both Optical and visual means as this dynamic star may one day just give us that big surprise we are all waiting for
Please report any observations of Eta Carina on this thread.
For further information on what we have been discussing so far, including helpful links, please lookherein the "Radio Astronomy and Spectroscopy" forum.
Hi Ron
I have been looking at Eta Car. fairly consistently this year. I thought last year that it was appearing brighter and in my opinion there is more detail available to view in one lobe, but that may be that I am getting better at seeing.
Do you know of any charts with comparison stars nearby to make brightness estimates?
I got this information from http://www.aavso.org/ql/results
At the top of the list, I used the chart information by the observer "SANG". This was obtained by clicking on his "chart" (4118 aiu).
Currently as of April 14th, Eta Carinae sits at mag. 4.9. A slight shift from what it has been sitting on at 4.7.
Though I have observed this star extensively, and researched much theory on it, I'm about to start an exciting journey of variable star observing with this star and learn as much as I can.
I really do hope others will join in and post their observations. It will be a fun, informative, informal way of observing such an exciting extrinsic cataclysmic Luminous Blue Variable star.
Great to see that within the first two posts, Ron's obs and your response Malcolm, matches up and makes for some very interesting observation reporting.
Les D are you able to help us further? I've come to understand the Sydney Observatory runs some variable star programmes, so perhaps you may be able to help us further.
Last edited by Suzy; 18-04-2011 at 12:03 AM.
Reason: typo.
This is an interesting development, and astute observing, Ron.
Keen eyes indeed. Ron, do you regularly follow variable stars?
Hopefully we'll have a clear sky for the next new Moon. I've been wanting to have a closer look at the Homunculous for the last three months. I've also set myself a task to sketch it from a dark site, and the Eta Carina Nebula too. This is my last effort on the nebula from Sydney done with my 17.5", over three hours. Eta Carina is the reddish star just left of the centre of the sketch.
Good articles too, Susy. Man, aren't variable star observers filling a niche slot. Cool stuff.
I observe the eta carinae complex quite extensively.Probably each time out with the scope.I might make a sketch of the homunculus nebula to show how it looks like now for future reference.
Firstly let me say I am not a variable star observer per se. Due to my change of job and family relocation I have done very little observing in the past 9 months. I had my first serious run back from a spell recently at Coonabarabran. I have always taken a major interest in Eta and its associated targets, consequently when I was at Coona recently I was quite interested to see what Eta Carina had done in the 10 months since I looked at it last. Seeing and mirror cooling didnt support magnification high enough in the 30" SDM to push any detail out of the Homunculus which was dissappointing. On the 1st and 2nd April I estimated ETA Carina at Mag 4.8, without reference to any other observers estimates.
I found this link full of helpful tips to observe variable stars. Here's a sample...
Quote:
Face the star without preconceptions. Wipe your mind clean of what the variable "ought" to be doing; record exactly what the eye sees. If you brood on the fact that the star can't possibly have jumped 0.5 magnitude since last night, you may try to "correct" your impression of it. This is the worst thing you can do to your accuracy, and it's worth understanding why.
Error in scientific measurement falls into two categories, random and systematic. Random error tends to cancel out in a predictable way after a while, just the way a coin will come up closer and closer to 50 percent heads the more times it's flipped. Systematic errors are those that never cancel out — for instance, if one side of the coin is weighted — and therefore they are more insidious. In the case of variable-star observing, systematic error corresponds to bias in the observer's eye and brain. So if you record exactly what you see without bias, your errors are more likely to be only random, and you can have faith that they will actually average out closer to the truth than any "improvement" you fudge.
Of course, be quick to throw out any estimate that you think results from some actual mistake or carelessness.
Center the stars in the field of view. Place the two you're comparing an equal distance from the field's center, or if this brings them near the edges, move each one to the center and examine it in turn. This is needed because some instruments don't fully illuminate the edges of the field — an effect known as vignetting — so stars near the edge are slightly dimmed. Vignetting is most likely at a telescope's low power, where variable-star work is usually done. Another reason for doing this is that the same star might look subtly different when it's near or far from the black edge of the eyepiece's barrel.
Keep your eyes moving. Scan back and forth between the stars you're judging, constantly checking and revising your impressions. If the variable seems to be a third of the way in brightness from star A to B, try to convince yourself that it's a quarter of the way, then halfway. Is it equally easy to talk yourself into each opinion? Then the truth probably lies between them. If one seems more plausible than the other, shift the assumption you started with and test on either side of it again. This testing of the uncertainty limits is called bracketing an observation, and you should try to make it a habit.
Use the out-of-focus method. It's easier to compare the brightnesses of disks than pinpoints, so twist the focus knob. The brighter the stars, the farther out of focus you can take them.
Choose variables of optimum brightness for your instrument. Stars within about a magnitude of a scope's limit all tend to look alike. Conversely, very bright stars won't have good comparisons nearby; in this case you'll have to go to a smaller instrument with a wider field. The naked eye is the best viewing system down to about magnitude 4, binoculars or a good finderscope down to 7 or 8.
Quirks of the human eye. Beware of three potential sources of error. (1) The Purkinje effect in the retina makes red stars grow brighter (compared to white ones) the longer you stare at them, another reason to keep your eyes moving. (2) Moonlight and light pollution also make red stars look too bright; against a gray background they stand out more than white stars do. Use extra caution under bright skies and mention the observing conditions in your notes. (3) Viewing angle. A star looks brighter in the lower part of your vision than in the upper part. Tilt your head so the line joining your eyes is parallel with the line joining the two stars you're comparing.
and the data really proves that sure enough Eta Carina is truly brightening. 
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