First up in this blog posting is the monthly OCA general meeting where this time the presenter, Dr. Robert Zellem, JPL, spoke on finding exoplanets and how amateurs can do "sciencey" type things by observing the latest transit times of selected exoplanets.
|Dr. Robert Zellem, JPL, speaks on finding exoplanets at OCA meeting (Source: Palmia Observatory)|
Dr. Zellem talked about finding exoplanets and how numerous of them are being found all the time now and how it is possible to begin looking if they can support life, as we know it, and how to find it. He was quite a dynamic speaker and he introduced us to the NASA Exoplanet Archive, a freely available internet database and tool for exploring known exoplanets.
I was intrigued by the idea that amateurs with small cameras, possibly even in polluted city lights locations, can make light curve measurements on some suspect exoplanet locations and help update the exoplanet's orbital period. How neat would this be! It turns out that the NASA identified exoplanets are likely to have identified by maybe one or two transit measurements around their respective home stars. It might have been measured just this one instance and not updated since then and this is where amateurs can come to aid big science by looking up possible exoplanets that have expected transits in their location and some predicted time and then measure the actual transit to provide an updated correction to the initial measurement of orbit period.
Now there are bound to be many questions regarding the requirements with the magnitude of the star and the predicted transit effects on the star's light curve and many of the stars are probably outside the magnitude limit achievable by amateurs with their smaller scopes and maybe more light polluted skies. But just the idea of making such measurements is kind of intriguing. Dr. Zellem mentioned that many of the exoplanets are "hot Jupiters" and as such have close in orbits and occlude maybe 1% of the home star's light during a transit. I have not done any more research on the topic but you can see in the screenshot below that their are many tools and options available to anyone wanting to try. Thanks for a very interesting presentation, Dr. Zellem!
Also it was announced that OCA Bruce Waddington had one of this astrophotos selected for the Astronomy Picture of the Day. Check out the image below of NGC4676, also known as The Mighty Mice. Thanks for that and congratulations, Bruce!
NGC 4676: The Mighty Mice made Astronomy Picture of the Day (Source: APOD and Bruce Waddington)
Well after hearing about Bruce's success, it would be nice to go outside ourselves and do a little observing, but the Scope Nights forecast was not very encouraging. With this sorry forecast we might just as well stay inside and study astrophysics and meteorology.
|Scope Nights app screenshot shows cloudy weather rest of this week (Source: Palmia Observatory)|
And yet, even with this poor forecast, when we were out for a final evening walk around the observatory grounds with Astronomer Assistants Ruby and Danny, the full Strawberry Moon looked magnificently bright and the clouds were not too objectionable. So, I took the following image, all in about two minutes of setup and effort with the easily transportable Nikon Superzoom P1000 camera. The focal length was set so that the full moon image took up the whole camera frame and the exposure time was increased about 5 times from the previous exposure of the waxing moon.
|Strawberry full moon with Nikon Superzoom P1000 camera (Source: Palmia Observatory)|
So, sometimes when the forecast does not look so good, we can still find an opportunity to photograph the full Strawberry Moon and for other times when the clouds are out and interfering with our night observing, don't curse them, study them, and this textbook, now in its 12th edition, is an excellent source for independent study. I have this book on my Ipad and while many technical textbooks don't do much justice to the equations, this textbook does an excellent job of allowing you to size the whole text and equations and diagrams to fit your own preferences.
|Meteorology Today by Ahrens and Henson is an ideal textbook for independent study|
I found three drawings dealing with the nature of clouds and how the nature of the spinning Earth and Coriolis forces affects winds in the southern hemisphere. This is especially relevant for those traveling to Chile for the total solar eclipse. The fact that we need to have our tracking mounts rotate in the opposite direction, since we will align mostly with the southern celestial pole, and that some storm systems will rotate in the opposite direction. I am not planning to take a tracking mount, but it is all part of the study of clouds.
First up is a picture showing the relative sizes of raindrops, cloud droplets and condensation nuclei. This is a convenient chart when you are trying to calculate the diffraction and scattering and absorption of light and radio waves and clouds. The fact that water vapor faces forces that help and hinder the creating of the first condensation nuclei is interesting and we see that without the help of some small dusty type particle it is hard for the condensation forces to exceed the evaporation forces.
|Relative sizes of raindrops, cloud droplets and condensation nuclei (Source: Ahrens & Henson, "Meteorology Today")|
|Earth rotation and weather patterns in northern and southern hemisphere (Source: Ahrens & Henson, "Meteorology Today")|
Another figure that was interesting is how the direction in which winds blow. It turns out that winds blow from regions of high pressure to regions of low pressure. So, since the equator tends to get more solar heat, which results in a high pressure region, the winds blow from the equatorial region towards the north in the northern hemisphere and towards the south in the southern hemisphere.. Ok, all of this is as expected, but when the Coriolis effects are taken into account, the winds tend to flow from west to east. This occurs because the Coriolis effects results in westward motion in both cases. There is so much more in the textbook so if you have any interest in getting a better understanding of weather and climate be sure to check out this easy to read textbook!
Ok, that is enough meteorology for this post, so let's get back to reviewing some of the other homework for our upcoming trip to Chile to observe the total solar eclipse. We shouldn't forget some of the cultural aspects of where we are going to be, so following up on a comment by Retired Big Oil Chemist, Dr. Arnold, who while visiting Chile on a cruise suggested that we try the "national drink" of Chile, the Pisco Sour. Hmm, ok, I'm up for that. So, as part of our pre-travel planning we looked around where we could sample a Pisco Sour and found that a local King's Fish House restaurant offered the famous drink on their menu. So, in the photo below you can see their version of the Pisco Sour. Hmm, to my martini trained palette, it was not quite up to my likes, but, hey, I'm all into experiencing what the world and its cultures have to offer. But the Wild Chilean Seabass dinner plate was very, very good. It was served with Miso-Yaki sauce and it was excellent. Thanks for the recommendation, Having fun in Hawaii, Eddie!
|Found a Chilean Pisco Sour on the menu at Kings Fish House (Source: Palmia Observatory)|
Ok, after doing our homework on the Pisco Sour, we had to do some more homework on some of the Chilean wines. After a visit to Total Wines, we stocked up for our homework with some Sauvignon Blanc, Pinot Grigio and Chardonnay by Porta wineries and some red Malbec by Colchagu Valley. Hmm, I suspect this homework is going to be different and hopefully more fun than studying general relativity!
|Getting ready for some "homework" pre-eclipse tasting of Chilean wines (Source: Palmia Observatory)|
Finally, if I have any energy left over from all of this homework, maybe I could get a bit of time and clean up all the parking permits that have accrued in the telescope delivery vehicle, just in the last couple of months. There are parking permits for various college seminars and colloquia and other hotel events. Yeah, ok, they keep piling up and it is time to clean up! Oh, what, so you say that this never happens to you?
|Parking permits for colloquia and seminars build up quickly in the telescope delivery vehicle (Source: Palmia Observatory)|