The Occultation of a W=11.1 Star by Fiducia

Thur morn Aug 8, 2024 at 2:37:26am

OWc page

This is a bright star, and a long duration, so very good prospects for a good mapping of the surface profile of this asteroid, and any moons it might have. Duration=3.1s. Alt=17, Az=83. The path includes all of the Santa Cruz Mtns including Karl, although getting too far west risks a short event or perhaps a miss.

It's not visible from home, so I'll try it from a better site. If fog allows, I'll try from the lake near High Street. If fog doesn't allow that, then Llama Lane, and if that's still not enough, the to Pineridge or even Sunlit Lane.

     

 

Results:

All 3 of our team got data - good!

Richard Nolthenius

I stayed at my new discovered good site, Llama Lane in Cave Gulch. Easy to get to, laid-back no problemo neighbors, open skies. I was here for the prior event just before midnight, and just stayed in my car and listened to a podcast for an hour until set up time for this next event, but did have to repack/unpack as the low altitude in the east was not ideal for my first spot 100 yds further east. The target was south of the Plieades, and was decently visible at 2x. I saw the event visually on the external monitor, and it seemed 1.5s long I'd guess.

 

magDrop report: percentDrop: 78.5 magDrop: 1.671 +/- 0.232 (0.95 ci)

DNR: 2.31

D time: [09:37:25.9986]
D: 0.6800 containment intervals: {+/- 0.0144} seconds
D: 0.9500 containment intervals: {+/- 0.0463} seconds
D: 0.9973 containment intervals: {+/- 0.1462} seconds

R time: [09:37:27.7186]
R: 0.6800 containment intervals: {+/- 0.0144} seconds
R: 0.9500 containment intervals: {+/- 0.0463} seconds
R: 0.9973 containment intervals: {+/- 0.1462} seconds

Duration (R - D): 1.7200 seconds
Duration: 0.6800 containment intervals: {+/- 0.0223} seconds
Duration: 0.9500 containment intervals: {+/- 0.0615} seconds
Duration: 0.9973 containment intervals: {+/- 0.1518} seconds

     

 

Kirk Bender

Observed from north of the UCSC upper bike crossing, also got data. But first...

While waiting for Fiducia, I recorded Andromeda's Parachute on the Watec 910hx at 64x. Andromeda's Parachute is a quadruple lensed quasar with a z =2.36 in Andromeda, discovered in 2017. Designation J014709+463037. There's a lensing galaxy that bends the light from the quasar into four sources with different time delays, combined visual mag of 14.4. The galaxy is 7 billion light years away, and the quasar is 11 billion light years away, or was, when the light left it. The quasar is located next to a 12.45 mag star, TYC 3279-1686-1, so I found the star in Sky Safari and did a goto RA Dec on the C8. I took out the focal reducer to get better separation with the bright star. I tried to see it visually in the 17.5" at GSSP in July but could not, maybe I could have with different eyepieces. JP told me about it, he saw it in the 25", and said it had changed in brightness when he saw it again. He saw it in the 17.5" on the Stanislaus trip in September 2022 and said it was fainter than the previous year. Frame from the watec attached, arrow at the quasar, next to the 12.45 mag star in upper center. Page on faintfuzzies.com with finder charts and discovery paper:http://www.faintfuzzies.com/OR-Jul022017-SR.html

And for the occultation...

Clear 1.4 sec event for Fiducia, 2x on Empire Grade.

magDrop report: percentDrop: 79.7  magDrop: 1.732  +/- 0.243  (0.95 ci)

DNR: 2.05

D time: [09:37:26.2928]
D: 0.6800 containment intervals:  {+/- 0.0128} seconds
D: 0.9500 containment intervals:  {+/- 0.0437} seconds
D: 0.9973 containment intervals:  {+/- 0.1243} seconds

R time: [09:37:27.6825]
R: 0.6800 containment intervals:  {+/- 0.0128} seconds
R: 0.9500 containment intervals:  {+/- 0.0437} seconds
R: 0.9973 containment intervals:  {+/- 0.1243} seconds

Duration (R - D): 1.3897 seconds
Duration: 0.6800 containment intervals:  {+/- 0.0203} seconds
Duration: 0.9500 containment intervals:  {+/- 0.0564} seconds
Duration: 0.9973 containment intervals:  {+/- 0.1337} seconds

 

 

 

Karl von Ahnen

Karl was able to find an opening in the trees to get this one, but just barely in time. Will review to be sure.