Stunning Dual Satellite Pass (3/21/17)

Observing Report by ASSNE Member Mike McCabe

Last night I went out to observe, and probably started setting up around 7:30 or so. For most of the setup time, I had the driveway lights on to make it easier to put everything together, but for the last few items I shut off the lights to start getting dark adapted. As I walked back to the scope just before 8:00 with the final pieces, I just looked up for a moment to scan the sky and see how things were looking. To my astonishment there were two new “stars” high in the southeastern sky that virtually mimicked Castor and Pollux. Set just a bit lower on the dome than the famous duo, they were both brighter than the familiar pair…and of course they were moving.

At first I was thinking Iridiums, because they both brightened and faded at virtually the same time, but I wasn’t sure because Iridiums travel in a virtually north-south path and this pair was heading SE/NW. Another reason that I initially suspected Iridiums is because they’re in the process of replacing them and I wondered if perhaps they had a couple running in tandem as part of the process. I watched as one faded dramatically but still remained visible and the other brightened again one more time before they both faded out of view somewhere south of Polaris.

I was intrigued now and vowed to try and remember to go on Heavens Above and figure out what they were. Well, I did this morning and BINGO! Got ’em! One was a Russian rocket body from a satellite that was launched in 1994, and the remnant still travels in a virtually perfect circle 640km above earth, and the other was a rocket body from something that Japan launched in 2001 which now travels in a hugely elliptical orbit around earth that varies in distance from 239km to over 31,000km.

Here’s the info on what I saw last night:

Luna (in daylight) 17:02 hrs 5 Mar 2017

Luna, Venus, and Asteroids (3/5/17)

Excerpted from ASSNE Member Pete Peterson Observing Report, Wishing Star Observatory

It’s cold tonight but the wind has fallen below 20mph and continues to fall. Sky’s crystal clear but seeing is poor. Tonight’s objective is to play under the stars, imaging with both SBIG and planetcam.

The 56% illuminated 7.38 day-old moon is very high on the meridian and it’s still daylight when a first set of images are taken (see image above).

Slewing to Venus there’s not much to see with such low magnification. It’s 1/3 AU distant and only 12% illuminated as it swings by Earth. At 50” diameter it’s about maximum for viewing.

Out after dinner, Luna is high and the sky is black. Maximum resolution on an 80mm scope is 1.5” and seeing’s never that good around here anyway. After imaging the moon, my night imaging also included a few quick easy asteroids:

  • 2011 WO41 is a 3.2 km sized Apollo currently 17.3 magnitude and 0.5 AU distant. Apparent motion is 2.1’/hr.
  • 11398 is a 3.6 km sized Amor now a relatively brilliant 15.3 magnitude. Distance is 0.28 AU and apparent motion is 2.5’/hr.
  • 2016 UU80 is a 397 magnitude Amor now 19.4 magnitude and 0.23 AU distant. Apparent motion is 1.7’/hr and uncertainty level is 3. (Orbital arc is just 126 days.)

A few comments: There’s a delicate balance between over and under exposure on lunar work. The camera sees color strangely. In the color daytime Short Tube image the Theophilus crater seems to be better defined than in a nighttime image that was processed monochrome. Given the capability of working a 19.4 magnitude asteroid in single 3 minute exposures, have to say conditions were good. Fun night!

Read the complete report (with additional images and imaging data) here.

March Meeting Agenda (3/11/2017)

ASSNE’s March 2017 meeting will feature Q&A roundtables on astronomy. How does this work? We will have six tables, each focused on a specific topic and staffed by 1-2 knowledgeable astronomers. Everyone else will be invited to pick a table, and ask questions, listen in, or generally discuss the topic with the “experts” for 10-15 minutes. We’ll then hit the gavel and encourage people to shift to a different table. We will do 2-3 rounds, depending on level of interest, and then have the rest of the meeting. These are the tables for our inaugural event:

  • DSLR Astrophotography
  • Guided Astrophotography
  • Visual Observing / Star Hopping
  • Specialty Observing (comets, asteroids, variable stars)
  • Gear – making, upgrading, etc.
  • Club Information – outreach, events, etc.

The meeting will also include a quick presentation on Sirius A/B and “Looking Up” — what to look for in the sky this month. If the weather is clear, we’ll observe afterwards. See you there!