Greetings from Palmia Observatory
Well it has been several week between posts so it is time to review some recent activity and first up is this slide from the recently completed workshop on Venus habitability.
There is a lot more interest in sending probes back to Venus to get a better history of the planet and to search for evidence of possible life that might have been present long ago. The best summary of the possibility of life (life, as we know of it) is shown in this slide by Giada Arney.
It is interesting to see the length of time on Earth, Mars and Venus that it was expected that life (as we know it) could have existed. As the conditions on the planet changed, then life became less and less likely. We see that Mars had only a relatively short period of time during which life could have existed, while Venus has a much longer time, billions of years, in which it could have been habitable. The length of habitable time is often determined by volcanism and liquid water being present. Pretty neat!
|Life on Venus might have persisted for billions of years (Source: Giada Arney, Venera D workshop)
There was a Falcon 9 launch from Vandenberg on November 23, so we headed out with DSLR and flimsy tripod to try to see any rocket red glare from OC. We have a good eastern view of the horizon from a location in Lake Forest, so that is where we set up and waited for the launch. It was a bit cloudy so for low on the horizon all we could see was a bit of red glare through the clouds.
|Falcon 9 launch from Vandenberg as seen from Lake Forest, CA (Source: Palmia Observatory)
As the rocket reach higher altitudes we were lucky in that the clouds opened up and we could see a little more of the rocket exhaust and plume. In this 1/2 second exposure, which turns out to be a bit too long, you can see the rocket's red glare and the exhaust plume, in addition to the rollicking dynamics of the flimsy tripod. Anyway, it was fun and exciting to wait and see if we could see the Vandenberg launch all the way down at our Lake Forest observing site.
|Falcon 9 engine exhaust as captured with DSLR on flimsy tripod (Source: Palmia Observatory)
Later in the week, we planned to search for the latest batch of Starlink satellites. The Heavens-Above prediction was for the recent launch to be visible in OC starting from the southwest and then going high overhead to the northeast. So, hooray, yes they were naked eyeball visible and we could easily track and follow them with DSLR on flimsy tripod.
|String of 48 Starlink satellites, with Jupiter bottom left (Source: Palmia Observatory)
As the satellites passed overhead, we estimated the apparent length to be about 6 degrees or maybe something like 12 full moons stuck side to side. The 1/2 second exposure was a little bit too long to identify individual satellites. A further complication was that the satellites were still tightly bunched together and had not been commanded to move to their separate orbits. It was, however, really great to see them pass overhead in a long string of lights.
|After passing overhead, the 48 Starlinks continue to northeast (Source: Palmia Observatory)
December is also a good month to follow the comet, C/2021 A1 (Leonard), which was just recently discovered on Jan 2, 2021 at the Mount Lemon Observatory, which is located 17 miles north of Tucson, and is still on our wish list of observatories to visit. It is currently visible in early morning hours and about magnitude 5, which is expected to get a bit brighter around December 16 or so when it becomes visible in the early evening hours.
OCA Ray Stann captured this great image of the comet from the dark skies of Anza, CA on December 4. Great shot and thanks for sharing, Ray!
|Great shot of Comet C/21 A1 (Leonard) from Anza, CA (Source: OCA Ray Stann)
Well, after seeing Ray's success, this lazy astronomer got up early on a fogless morning and went outside with DSLR and flimsy tripod, in city lights viewing, and tried also to capture an image of the comet.
This DSLR image, 155mm, 15 second exposure, shows the comet just barely visible. Arcturus is at the far right and the comet is left of center in the middle of the frame. Longer exposures on the flimsy tripod just showed more star trailing. The morning skies were also starting to light up at about 5:45am and resulted in a lot of background light. We might have to get out the tracking mount to get better exposures. Maybe later in the month we can try again when the comet is supposed to be brighter in the early evening hours.
|Comet Leonard barely visible, left of center middle (Source: Palmia Observatory)
In other space related news, we have always enjoyed following the ongoing construction activities at the SpaceX facility in Boca Chica, TX. In this next photo showing the majority of the Starship launch area, look at the relative size of the BN4 booster, at the far left, next to the Starship SN20, in the middle, and then two short stubby, test tanks with the orbital launch tower at the far right.
When I first saw this photo, I said "how are those two short stubby and wide test tanks related to the tall skinny BN4? Well, it turns out that the two short stubby test tanks were used to test and verify the design of the tanks in BN4, and in fact are the exact same size in diameter. What? It just looks as if the two short stubby tanks are much wider than the BN4 booster and in reality have the same exact diameter.
This must be some sort of optical illusion caused by the telephoto lens and the distance between camera and each of the tanks and booster. In the next paragraphs we will use some photogrammetric techniques to show how we can measure the horizontal distance between Starhopper, on the far left, ad the launch tower, on the far right, and use the estimated distance of 360 meters.
|Are the two short stubby test tanks really the same diameter as B4 booster (Source: NASA Spaceflight)
Let's use this photo to do some photogrammetry and make estimates of the telephoto lens used and the distance to the observed objects. In this next image we see the orbital launch platform at the left and the original Starhopper prototype at the far right side. Remember that the original Starhopper, which first completed and demonstrated the first test hop of flying up in the air and then successfully landing again, back on August 27, 2019, has the same diameter, 9 meters, as the current version of the Starship
|Photo of orbital launch platform and Starhopper in the distance (Source: LabPadre)
If we analyze the above photo we find that the apparent diameter of Starhopper is equal to 1/10 the width of the photo. Suppose that the photo was taken with a 300mm telephoto lens with camera sensor of 22.3mm wide. Then we can calculate that the distance between the camera and the Starhopper is just equal to 9 * 300 / 2.23 = 1216 meters. But the orbital launch tower is seen to be in the foreground and given its diameter of 18.3 meters, we can go through the same optics calculation again. The orbital launch platform occupies 29/100 of the image width, so the distance to the camera is calculated as 18.3 * 300 / (0.29 * 22.3) = 856 meters. So based on these estimates, the Starhopper is 1216 - 856 = 360 meters behind the launch platform. So this distance seems to be a pretty good estimate based on the first photograph that shows the relative side to side distance between the Starhopper and the launch tower. Note that the important data point for this type of analysis is the known diameter of Starship and Starhopper. The assumed 300mm telephoto lens is not critical.
We can also report in this blog post the resolution of the mystery object first photographed in west Texas as back in August we visited the Blue Origin launch facility near Van Horn, TX. We spotted this large object off in the distance from the main highway, which I first interpreted as some sort of large radio dish antenna. I tried to photograph it, but the focus was off and all we came back with is this photo below.
|Strange object off of highway 54 between Blue Origin test site and Van Horn, TX (Source: Palmia Observatory)
Just recently, we discovered that that location corresponds directly with the Spin Launch facility. Spin Launch is an experimental new technology company that claims to be able to launch satellites into orbit, not by using rocket technology, but by rapidly rotating the satellite and using centrifugal force to launch the satellite into orbit. Wow, that sounds really far out. They rotate the satellite on a long arm in a vacuum chamber and then when the satellite is released, it travels through and breaks an airtight membrane and then travels up into orbit just by its own inertia.
Here is a photograph of the actual test location. This is what we saw from the road, but the image taken then was out of focus. More details of the technology can be found at their website: www.spinlaunch.com
|Spin Launch test site along highway 54 near Van Horn, TX (Source: www.spinlaunch.com)
In other Boca Chica news, a new photographer who has started doing livestream broadcasts from there, Starship Gazer, captured this group of visitors being escorted around by Elon Musk. Seeing the little dog tag along reminded me of our recent watching of the the classic, "The Wizard of Oz." Thanks for all the videos and livestreams, Starship Gazer; you are making it more difficult for the rest of us to justify flying down to Boca Chica again, just to keep up on what is happening there.
|It might actually be Elon's dog, "Marvin", but who knows (Source: Starship Gazer with comments by Palmia Observatory)
Speaking of little dogs, Astronomer Assistant Ruby, participated in a philosophical experiment. Not that she consented to it, but she was there nonetheless. You all know of the philosophical question about things like if a tree falls in the woods and no one hears it or sees it, did it really make a sound? Well we generalize this philosophical question to: " Does an object continue to exist when no one is looking at it?" This issue is the basis of the difference between idealism and realism.
So, to test this idea, I just took a 7.5 second video of Astronomer Assistant Ruby while she was sleeping and I was not looking at her. Do you know what happened when we reviewed the video? Well of course, she just lay there sleeping for the whole 7.5 seconds. Now if we treat this as a real scientific experiment and report it in the language of the scientific method all we can say is that "she continued to exist for the 7.5 seconds of the experiment and was still there when we returned our gaze to her." The scientific method does not disprove or prove anything it only sets limits based on the data. Some philosophers would say that all we know is that the dog persisted for 7.5 seconds and might have disappeared if we had continued the video observation much longer. You see this type of distinction even in tests of general relativity where the results show the estimated range of applicability, not that GR is correct in areas where it has not yet been tested. Anyway, thanks for helping out, Ruby!
|Does Astronomer Assistant Ruby exist when no one is looking? (Source: Palmia Observatory)
Ok, ok, let's get back to some more serious stuff and leave the philosophizing to our ongoing philosophy Meetups. There are so many know YouTube podcasters following all sorts of space activity and you might also enjoy following "Ellie in Space." She is one of my online "girlfriends." In this video she toured the Rocket Garden in Promontory, UT. Ellie travels around and interviews other SpaceX bloggers and facilities and provides interesting updates on what s going on in the field. After seeing her podcast, we said we need to put visiting the Rocket Garden on our travel itinerary. Thanks for everything, Ellie!
|Checking out Rocket Garden in Promontory, UT (Source: https://www.youtube.com/watch?v=pQTl5t8GlUE)
So, that is it for this post. Be sure to go out and see if you can find comet Leonard and watch the latest launch of Blue Origin's NS19 spaceship with new astronauts.
Until next time,