Blog / Monthly archive / September 2009
September 2009
Well on down the slippery slope
Eclipse is underway (V = 3.23 on 9/25/09)and the debate over when First Contact really occurred has begun. Initially, Jeff Hopkins figures it to be RJD 55072 (late Aug) while Richard Miles likes a date several days prior to that (mid-August). Whether the final answer is JD 2,455,072 or a week earlier, in either event it appears to be at least one week after predicted start (55055, early August). This arguably means further changes in eclipse shape and duration can be expected. Read more
Looking at the Light Curve III: Thar Be an Eclipse
The third post in our series on light curve analysis looks at both recent data and data from previous eclipses to answer the age-old-question: Who shot JR? Has the eclipse started in visual light?
Slip sliding away...
Jeff Hopkins, photon-counting, reports that epsilon Aurigae has faded to match eta Aur at V = 3.17 on the morning of 15 Sept 2009. If you have been hesitating to get out and see the eclipse, NOW IS THE TIME to get in gear and watch it happen. If you have any sort of digital camera capable of recording the scene, start recording and archiving your data. Over the coming weeks, we anticipate posting more instructional material on the Data Analysis formum about how to process your images and deduce magnitudes - from visual comparisons as found in the 10 Star Tutorial, to aperture photometry tools available online (such as IRIS - http://astrosurf.com/buil/us/iris/astro/astro.htm - or with licensed software like CCDsoft, MaximDL, MIRA, etc...). Happy observRead more
What a difference a week can make!
Seems like epsilon Aurigae has decided to take the plunge this week, dropping to an estimated 3.14 mag visual as of Friday morning 9/11/09 Denver time - down by nearly 0.1 mag in just under a week. Fast phase may have arrived early - keep watching!
Robin LEadbeater has posted an excellent summary of his spectroscopic monitoring in the form of a poster presented at a recent BAA meeting:
http://www.threehillsobservatory.co.uk/astro/spectra_40a.htm
Check it out!Read more
Waiting for Godot...
Samuel Beckett's play features characters who are simply hanging out, waiting for their friend Godot to show up. It may be beginning to feel this way with epsilon Aurigae too, as the slow phase of ingress grinds on. The current photometric V = 3.05 level suggests we are still within the range of normal out of eclipse light variation. However, the non-optical brightnesses are in decline, especially the I and J bands in the near-infrared.Read more
Avoiding Bias: Simonsen's Rules for Variable Star Observing
Check out Mike's advice for avoiding bias. Among my favorite advice:
If you see the observations of some other observer(s) beforehand-Read more
- Assume they are lying to deceive you!
- Know they are bad observers, so their opinion is worthless!
- They could be, and probably are, completely crazy. How many variable star observers have you met? I rest my case.
Looking at the Light Curve II: Hints of an eclipse?
You're sending in more data and it's helping! We have an updated forum post about new evidence for the eclipse in the light curves. What's your say? Is it starting? Read the light curve and make a prediction.
Form your Teams!
I am happy to announce that the first phase of the Team section of the Citizen Sky website is now up and running!
You can start your own team or join an existing team. (You can search existing teams by keyword or see a list of all teams.) Team leaders have the ability to make team membership open to anyone, or if they are looking for something very specific, team leaders can moderate the joining process. Once the team has all of the necessary skills represented in its membership teams can even be closed.
Members of each team have the ability to create team posts. These posts can be public (anyone can read them) or private (only other members of your team can read them.) Read more
