Observations - 10/03/20

Hello everyone.

The skies were reasonably clear and the winds calmed down considerably on Tuesday night 10th March 2020 from 8 to 11.30 pm.
So out I went with my William Optics 158 mm F/7 apochromatic refractor. As many of you know it sits on a Berlebach Planet altazimuth mount. There is also a William Optics 70 mm F/6 small apo fitted which was required to observe certain conjunctions.

1. Who wouldn't go straight for Venus? It has now reached -4.4 in magnitude. Uranus, on the other hand, had a magnitude of +5.9. In my small apo, I could easily fit both planets in a 6 degree field of view at 11X. There was the very welcome addition of an orange / red K5 star right next to Venus. 19 Arietis has a magnitude of +5.7. Venus was pure white and she was 58% lit. She was shimmering quite a lot at 167X. But still 19 Ari fitted in the same field of view. Venus and Uranus were 3.5 degrees apart. Uranus was seen as a very slight green disc at 112X. It was my first time to observe it so low in the north western sky.

2. Off I went to Cancer the Crab. M44 was my starting point. The hugely famous open star cluster was easily found at 11X; and looks most impressive at 40X. Don't go any higher! It won't fit in anything wider that a 2 degree FOV.

3. But what can I say in regards my favourite triple star? What a magnificent sight Zeta Cancri (Tegmine) is. Even at 40X A and C are a wondrous double. I then increase up to 112X; and then at 140X A and B are trying to split! Through my 6.7 mm Meade eyepiece, which aptly gives me 167X, A and B are split with the smallest of black gaps in between them. Wow! Calm nights always pay dividends. 225X is seriously excellent too. The magnitudes are: A = 5.3. B = 6.3. C = 5.9. Sep's = 1.142" (narrowing) and 5.9". PA's = 5 and 64 degrees. All these figures come from www.stelledoppie.it . I could see no colours at all in any of the stars. All white to me. I reckon that makes the system very attractive.

4. Epsilon Hydrae is a new favourite of mine. It is a true binary. Its magnitudes are A = 3.5, C = 6.7. B is not visible. Sep = 2.825". PA = 310 degrees. Again, because of the calm conditions, I only required 112X to split it. What a real thrill that was. 140X and 167X were very good also. Component A is yellow - white. B has a slight blue hue.

5. The rest of these doubles are very near Epsilon Hya. A 2752 might be an uncertain double, but it is a relatively easy to see. Magnitudes: A = 9. B = 11. Sep = 5.1". PA = 231 degrees. 112X was sufficient to see it split. 140X and 167X were that bit better to see the B component. Both stars are white. A stands for Robert Grant Aitken who lived from 1864 to 1951. He worked in California.

6. Stf (Struve) 1290 is a real gem! Magnitudes: A = 7.4. B = 9.2. Sep = 2.8". PA = 325 degrees. I refused to go higher than 112X. I had the big thrill of seeing a delightful black gap at that power. A is blue - white. B is white. One wonders how it can be an uncertain double. But never mind; it's worth seeking out.

7. Stf 1286 is less exciting but it is a true binary. Magnitudes: A = 9. B = 10.8. Sep = 29.2". PA = 82 degrees. Split at 40X and 112X. A is yellow. B is white.

8. Stf 1267 is a tough uncertain double. Magnitudes: A = 8.2. B = 11.5. Sep = 10.9". PA = 61 degrees. So faint was the secondary I needed 225X to get a glimpse of it. A is quite a decent red star.

9. BU 335 proved difficult too. It is a true binary. Magnitudes: A = 7.5. B = 9.4. Sep = 2.6". PA = 265 degrees. Surprisingly I required 225X to get a black gap between them. It just wouldn't split at any lower power. A is yellow - white.

10. Finally I observed a new (to me) carbon star in Cancer. TYC 223-509-1 is my 3rd carbon in this faint constellation after X and T Cancri. Of course it is much fainter that either of them. But at least it's not a variable star. I could see the 10.3 magnitude pin point of light at 40X, 112X, 140X, 167X and 225X. It is faint, but its orange - red hue was observed satisfactorily on this occasion.

Thank you for reading.

Comments are always welcome.

Clear skies,

Aubrey.

flt158 wrote: But what can I say in regards my favourite triple star? What a magnificent sight Zeta Cancri (Tegmine) is.

Excellent report again Aubrey. Have you observed the Beta Monocerotis triple btw? Really superb and possibly even superior to Tegmine imo.

Finbarr.

I keep telling myself to observe Beta Mon, Finbarr.
Some night I will do so.
By the way, I have been observing Zeta Cnc every year since 2013.
That's 8 years.
It stills blows me away!
Of course it is getting tighter each year.
But I do love Iota Cas and Psi Cas too.

Clear skies when the rain goes away, Finbarr

Aubrey.

Hi Aubrey,

What a great report to read: planets, doubles, triples, carbons, and open clusters. 

It seemed like you had favourable conditions too...nothing like calm clear night! 

Looking forward to reading your next report from the Crab. 

Clear skies, 

Darren.