Well here we are on a cloudy day and not much of a chance of nighttime observing and with the cloud of coronavirus or COVID19 hanging all about us.
|Cloudy weather with local mountain view (Source: Palmia Observatory)|
Now, my seminar notebook was completely filled up so I had to pick up a new empty one. But with all of the cancellations of events because of COVID19 concerns it might be a while before I need a notebook.
|My old notebook was full, but new one is not needed much because of event cancellation (Source: Palmia Observatory)|
So, far we have seen the APS March Meeting in Denver was cancelled and just received word that the APS April Meeting in Washington, DC, was also cancelled. Darn, I had hoped to attend that meeting!
But more to current events, we now see cancellations of local college seminars and colloquia. The local ham radio meetings and the local OCA monthly meetings have also been cancelled. Many theatre and sports events and even some schools are also being cancelled and we just heard that Disneyland is also closing.
I also was scheduled with airfare and hotels to attend the 51st Lunar and Planetary Society Meeting next week in Woodlands, TX, but that too has been cancelled. It was easy to get out of the hotel reservation, but the airfare also included our little adventure to visit Boca Chica, TX and peer through the fence at the SpaceX launch complex there. Too bad the ticket cancellation and rerouting fees amounted to almost as much as our initial ticket price. Maybe we should of just cancelled the whole thing?
Anyway, SpaceX continues with the Starlink Sixth Mission, which is currently scheduled for Saturday, March 14. So if the clouds go away we may have a chance to see the "string of pearls" before the satellites transition to their higher operating orbit. It turns out, if you are ever planning to see a launch or follow up with Starlink observations, you can often get advanced notice of the launch on various unofficial Tweeter feeds that identify the launch date several days before the KSC announcement.
|Latest launch schedule for the 6th Starlink Mission (Source: Kennedy Space Center)|
By the way, have you ever wondered how the predictions about when and where the Starlink satellites can be observed? Well, I finally found a published paper going over the details of some of those calculations. We know that satellites are only visible because of reflected sunlight. In this diagram, from a paper by O. Hainaut & A. Williams, we see the required conditions of altitude and relationship to the sun are key determinants. The geometry of the situation is the key thing but the unknown is how much of the reflective surface of the satellite is available and its orientation with respect to being able to reflect back to the Earth observer.
|Calculating when satellites will be illuminated by the sun (Source: O. Hainaut and A.Williams, arXiv:2003.01992v1)|
Finally, as we put up with cancellations and trying to stay safe and uninfected, we can remember to follow some simple health preventive steps. I saw this cute Facebook post, which is especially relevant now. Thanks for that Marylea!
|This system of social disapproval might be very effective! (Source: maybe Bizarro, but found in Facebook post)|
So, if our upcoming flights all go Ok, we will report next time on what we find out about SpaceX launch facility in Boca Chica, TX.
Until next time,