Greetings from Palmia Observatory
Well the age of commercial space and commercial space astronauts and tourists is here. It was really thrilling to see William Shatner, also known as Captain Kirk, now 90 years old, go into space as a guest aboard the Blue Origin Spaceship, NS-18.
Here we see him stepping out of the space capsule after journeying to the edge of space.
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| Captain Kirk walks out of capsule after rocket ride (Source: PBS News Hour) |
Well, if you don't have the notoriety of William Shatner to get a free ride into space, you can sign up for an airplane ride and experience weightlessness yourself. This coming Saturday, this Resident Astronomer and Science Nerd, Scott, will board the aircraft and experience for our selves about a total of about 5 minutes of weightlessness, which is probably more than was experienced aboard the Blue Origin NS-18 flight. So check it out and sign up at www.gozerog.com. Yes, it is a bit pricey, about the same as a two week cruise, but you might not want to miss out on the experience.
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| Some happy folks in zero g (Source: www.gozerog.com) |
Also, as long as we are talking about adventures and cruising, we just booked this January 2022 cruise that travels between Manaus and San Juan. This is a modified version of the cruise that we had booked before the pandemic that included a stop in San Juan, where we could visit the Arecibo Observatory. Even though the telescope has now been abandoned after the antenna receiver dome collapsed, it is still on our bucket list.
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| Cruise itinerary between Manaus and the Amazon and San Juan (Source: Viking Cruises) |
One interesting stop on the cruise is the Iles de Salut, which is a location more recognizable by the location of the infamous prison located on Devils Island. This island prison is about 20 miles off the coast of French Guiana, which has an interesting history of being the location of the famous Guiana Space Centre, from which many satellite missions are launched, including the upcoming launch of the JWST, now scheduled for December 18.
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| James Webb Space Telescope (JWST) launch date (Source: Mars Society 2021 Convention) |
Now we might not get a chance to stop at the launch site on the upcoming cruise since the launch site is located near Kourou, French Guiana, with the Salut Islands just offshore. In this diagram you can see the various launch facilities used for some Soyouz and Ariane rocket launches. Note that the Salut Island is where a Cinetheodolite tracking system is located.
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| Centre Spatial Guyanais outside Kourou, French Guiana (Source: Wikipedia) |
I don't have any information on the Cinetheodolite on Salut but here we see on example located at the Air Force Space Command center at Cape Canaveral, FL. The theodolite provides angular measurements of the target based on the line of sight to the target.
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| A Cinetheodolite at Air Force Space Command at Cape Canaveral (Source: Wikipedia) |
Ok, that is enough about future launches and cruises, let's return to some preliminary night sky observations. As many OC residents experienced we had some nice lightning activity last week. This was quite enjoyable, since it doesn't happen here very often, to see the flashes and hear the thunder from the lightning.
I didn't want to get out in the rain and also didn't want to setup a camera outside in the middle of a field, but did want to try capturing some of the lightning flashes. So, just setting up outside the door, still under an overhead awning and staying dry, I set up the flimsy tripod and camera. This first image is taken with DSLR 10mm lens and 15 second exposure. No lightning here!
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| Hiding under an awning to stay safe and dry, DSLR, 10mm, 15 seconds (Source: Palmia Observatory) |
There were many lightning flashes all around but I could not capture any of the lightning strokes overhead. I forgot that maybe the best approach would have been to just take a video and wait for the flashes to come into view. Next time! Anyway, there was at least this one photo capturing the lightning flash somewhere off in the distance.
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| Finally, a lightning flash, DSLR, 10mm, 15 seconds (Source: Palmia Observatory) |
Finally, let's come back to a topic of interest to photographers and physicist wannabes and that is polarization filters. I found two old sheets made of polarized see through plastic. When you aligned two of the sheets so that they are perpendicular to each other, most of the light is blocked and is not transmitted through the combination of filter sheets.
Now the question for physicist wannabes is how to tell what is the polarization of the sheets? How to tell is the filter sheet is aligned with vertical polarization or horizontal polarization? Well one way is to view a light source with known polarization and see which orientation of the filter results in the most and least attenuation.
One source of mostly polarized light comes from light reflected off of a surface. In the case of this photo of light reflecting off of a blacktop roadway, we recall from a study of Brewster reflection that the light coming to us will be mostly vertically polarized.
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| Reflection off of asphalt roadway, DSLR, 300mm, 1/125 sec (Source: Palmia Observatory) |
This image was taken just by moving the flimsy tripod to the office window and pointing the camera out so that the reflection from he street comes right into the camera. Then we can take two more images, one with polarizing filter held vertically, as shown, and then one more with the filter held in a horizontal position.
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| DSLR setup with section of polarizing film held in vertical position (Source: Palmia Observatory) |
So, if most of the reflected light is vertically polarized, then by measuring the light intensity that comes through the filter, placed in different orientations, call tell us what the orientation of the filter sheet is. In this next photo, the filter sheet is held vertically as shown in the previous photo. Note how the amount of reflected light in the photo is reduced. This is to be expected because the filter removes some of the light entering the camera. But we still don't know what the orientation of the filter sheet is.
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| Roadway reflection with filter held vertically, DSLR, 300mm, 1/125 sec (Source: Palmia Observatory) |
To find out what the polarization of the filter sheet is we need to take one more photo, but this time we turn the filter sheet so that its orientation is 90 degrees off. The filter sheet is now horizontal. Note this time, the image is not as dark as in the previous photo.
So, this must mean that the first orientation blocked more of the mostly vertically polarized light, so when the filter sheet is held in the vertical position, it does, by chance, also block mostly vertically polarized light.
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| Roadway reflection with filter held horizontal, DSLR, 300mm, 1/125 sec (Source: Palmia Observatory) |
Until next time,
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