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Talk to 4th Graders;
Asteroid 3200 Phaethon

Posted: 14 December 2017

Clouds returned on Saturday, 9 December 2017, and continued until Wednesday, 13 December.

Wednesday morning, 13 December, I gave a talk on astronomy and light pollution to 4th grade students at the Mountain Vista School in Oracle. The students were awesome and very smart. I presented the class with two EclipseView telescopes that had been donated by Meade Instruments. The students and teachers were very excited to receive telescopes. After the talk we took one of the telescopes outside and viewed the Sun. Here are the students and one of their new telescopes. I'm the tall kid in the black shirt on the right.

Photo courtesy of Mrs Julie Formo, teacher

This is a quick iPhone photo I took of the Sun through their telescope:


The students will be doing some light pollution research projects this month and will report back in January. I look forward to seeing what they do.

Open: Wednesday, 13 December 2017, 1816 MST
Temperature: 69°F
Session: 1175
Conditions: Clear

Equipment Used:
12" f/8 LX600 w/StarLock
2" 24mm UWA eyepiece
2" 8-24mm zoom eyepiece
Focal Reducer

D7200 DSLR

I first SYNCed the observatory clock to WWV time signals.

1822 MST: LX600 ON, StarLock OFF, High Precision OFF.

Viewed the planet Neptune, 102X. Switched to a 8-24mm zoom eyepiece. Neptune's disk looked nice at 305X. Then viewed the planet Uranus, 305X. That was a really nice view of the planet.

Switched back to the 24mm eyepiece. Slewed the telescope to the star Capella and SYNCed the AutoStar in preparation to observe and hopefully photograph the Asteroid 3200 Phaethon. This asteroid is approaching the Earth (won't hit us) and will be closest on Saturday, 16 December. Phaethon is the source of the meteors that appear during the Geminid Meteor Shower which is currently happening. You can learn more about Asteroid 3200 Phaethon at Sky and Telescope.

I then used SkySafari Pro on my iPhone to check the current position of Phaethon. It was close to the star Algol so I slewed the 12" telescope to Algol and SYNCed the AutoStar on it.

1854 MST: Wi-Fi ON. Used SkySafari Pro to GOTO the asteroid. I then began trying to locate the rapidly moving asteroid against the background stars. 1905 MST: confirmed sighting of Asteroid 3200 Phaethon. Once located it was easy to see its motion in about 30 seconds. I switched to the zoom eyepiece and promptly lost sight of the asteroid. I was never able to relocate it with the narrow field-of-view of the zoom eyepiece. Switched back to the 24mm UWA eyepiece (102X). I continued to do GOTOs to the asteroid using SkySafari Pro to try to place the asteroid in the center of the field-of-view. 1937 MST: reacquired Phaethon visually, 102X.

I then began setting up to photograph the asteroid. Mounted the D7200 DSLR at prime focus + focal reducer. Focused using the star Algol, then returned to Phaethon using SkySafari Pro. 1954 MST: StarLock ON.

This is a StarLock autoguided image of Asteroid 3200 Phaethon, 1 minute, ISO 1600, White Balance 3570K:


During the 1 minute exposure the rapidly moving asteroid appears as a streak.

I then did 5 exposures every 1 minute using a 10 second, ISO 3200, WB 3570K, exposure. The images have been combined in this animated GIF to show the asteroid rapid motion over 4 minutes:


2007 MST: StarLock OFF, Wi-Fi OFF.

Removed the camera.

2019 MST: LX600 OFF.

Close: Wednesday, 13 December 2017, 2029 MST
Temperature: 55°F
Session Length: 2h 13m
Conditions: Clear

I have posted a review of the ScopeStuff Red Dot Finder for SLR Hotshoe. If you do sky astrophotography you will find this accessory definitely worthwhile.

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