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 Post subject: Pallas at Opposition!
PostPosted: Sat Oct 28, 2017 6:08 pm 
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http://astro.vanbuitenen.nl/minorplanet/Pallas

8.2 magnitude in Eridanus just below 11 Eri.

October 30th, 2017 at 00:02

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PostPosted: Sat Oct 28, 2017 10:10 pm 
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The linked page indicates (2) Pallas will be at opposition on 29-Oct-2017, but no specific time is listed. The U.S. Naval Observatory's MICA Software calculates opposition at 23:38 UT on 28-Oct-2017, which rounds to 0 hr UT on 29-Oct-2017. This is also the value given in the 2017 RASC Handbook.

So, for those of us in New Jersey, (2) Pallas was at opposition tonight at 7:38 pm EDT. What's the significance of your date and time "October 30th, 2017 at 00:02"? Is it EDT or UT?

(2) Pallas crossed the border from Eridanus into Fornax earlier today, about 2 pm EDT on 28-Oct-2017. It's now just under a degree ESE of 11 Eri (a.k.a. Tau 3 Eri*). It will loop in Fornax, then cross into the southeast corner of Cetus around January 13, 2018, on it's way back into Eridanus around January 22, 2018.

Thanks for the heads-up, I'll have to spot it once the weather cooperates. It will be a good target for my new 15x56 binoculars.

---------------

* Interestingly, there's an approximate 20° chain of nominal 4th magnitude stars in Eridanus running from Tau 1 to Tau 9 Eridani (mostly in the 4.x magnitude range, with a pair of outliers at 3.7 and 5.2).

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PostPosted: Sun Oct 29, 2017 7:11 pm 
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My astronomy software indicates that asteroid (2) Pallas it will be low in the sky, only about 26 degrees above the horizon, and far below the ecliptic when it is directly south tonight (tomorrow morning) at 1:28 am EDT from my location (Whiting, NJ). I'm surprised it's so low in the sky and so far from the ecliptic.

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PostPosted: Sun Oct 29, 2017 9:08 pm 
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The reason (2) Pallas can get so low is its 35° orbital inclination (to the ecliptic). It's much steeper than (1) Ceres at 11°, (3) Juno at 13° and (4) Vesta at 7°, but I don't know any particular reason why it is.

Regardless, the 26° altitude at transit won't be so low that (2) Pallas can't be spotted with binoculars -- after the weather clears out. Perhaps I'll try to catch it on Monday night (Oct 30-31) based on the current Clear Sky Chart.

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PostPosted: Wed Nov 01, 2017 11:13 am 
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It was pretty clear on Tuesday morning, October 31, 2017, so I went to the relatively dark skies of Carranza Field in Wharton State Forest, arriving around 3 am (moonset was at 3:10 am EDT). Using 15x56 binoculars, I soon spotted magnitude 8.2 (2) Pallas near 11 Eri (Tau 3 Eri), and shortly after, I also spotted magnitude 8.5 (1) Ceres, which was favorably positioned in Cancer, near M44.

I had considered trying for all of the “big four” asteroids in one night, but (3) Juno, in Scutum, was getting low in the southwest after sunset, and even worse, it’s much dimmer at magnitude 10.8 now. The brightest of the four, magnitude 7.9 (4) Vesta, is in Virgo and doesn’t rise until the start of astronomical twilight, about 6 am EDT.

I also took some snapshots to record their positions. They’re currently at the top of my web page. Before I left around 4 am, I was also able to spot both Pallas and Ceres with 10x50 binoculars.

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