• Choose a post by category or constellation

  • Learn the Night Sky

  • Search strategies

    Use the Search box below to find doubles by popular name, RA, or telescope size. For example, a search on "15h" will find all doubles we've reported on that have an RA of 15 hours. A search for "60mm" will find all doubles where we used that size telescope.
  • Advertisements

Planet Posing as Double Star !!!


(Updated September 23rd, 2012)

Uranus will be posing as a double star through the end of September!

This will be a great time to catch sight of it, and still satisfy that irresistible urge to split a pair of close “stars.”

You’ll find it closing quickly on 44 Piscium, with separations ranging from 10.8′ to an interesting 1.4′.

The separations listed below are as of 5 PM PDT/8PM EDT (2359 UT) on the dates indicated.  The best observing times will be from about 10 PM to 2 AM local time, so the separations shown here should be very close to what you’ll see:

9/18:  10.8′
9/19:    8.4′
9/20:    6.0′
9/21:    3.7′
9/22:    1.4′
9/23:    1.4′
9/24:    3.7′
9/25:    6.1′
9/26:    8.5′
9/27:  10.9′

I’ve included a chart below to show Uranus’s location just to the east of the Circlet below the Great Square of Pegasus.  You’ll find it holding down the southern point of a triangle formed with Delta (δ) and Omega (ω) Piscium.   If you’re viewing in a metro area with bright skies, binoculars will be a big help in locating it.

Stellarium screen image with labels added — click for a larger view.

For those with GOTO mounts, the coordinates (epoch 2000) for 44 Piscium are 00h 25m 24s, +01° 56′ 23”.   The HIP catalog number is 2006, and the SAO catalog number is 109192.

44 Psc is a 5.8 magnitude class G5 star, so it should appear yellowish.  Uranus shines at a magnitude of 5.7, and should have a bluish hue to it.  Look for 6.15 magnitude HIP 1421 just barely northwest of Uranus.  That’s a class K0 star, which should have at least an orange tinge to it.

So what you should actually see are three points of light — one  yellow, one blue, and one orange — which should make quite a sight in binoculars and telescopes!

Thanks to Sky & Telescope’s web page for the separation numbers!


I finally got some clear skies, so I aimed my six inch Celestron f/8 achromatic wonder skyward and found this dazzling sight:

Holy apparitions of Albireo! For a moment I thought I was in Cygnus! (East & west reversed to match the refractor view, click on the sketch for a larger version).

I was beside myself with technicolor joy!  I didn’t expect anything like this kind of color!  Of course, six inches of aperture helped bring the colors to life, but I also found them waiting for me in the 60mm f/15 I have mounted on the Celestron six inch.  In a 20mm TV Plössl (45x) they were considerably subdued, but still quite obvious.   The fact that the first quarter moon had set about an hour earlier gave me the added advantage of a dark sky.

After I finished the sketch, I dropped a 5mm Radian (240x) into the diagonal of the six inch refractor to see what would happen.  44 Piscium preserved it’s sharply focused yellow-gold glow, with the attractive addition of a dancing diffraction ring around it.  Uranus offered quite a contrast in color — a dusky pale turquoise, almost translucent, and just slightly out of focus.

I marveled at that color for what seemed like forever  —-  it had me wondering why some nineteenth century observer had never suggested Uranus as a world covered with an ocean.   If you didn’t know it was a frozen ball of ammonia and methane, it would certainly seem it could be a blue-water world.

If you haven’t had a chance to catch this pairing, take a look when you get a chance.  Uranus is now moving farther away from 44 Piscium, so don’t wait too much longer.

I’ll leave you with the Greek spelling for this ancient god of the sky:  Οúρανóζ !!!

Clear Skies!  😎


4 Responses

  1. Hi John!
    You may have an error in your RA for 44 Psc. From Stellarium I get 0h,25m,24 seconds. I sent my scope to 02 hours and buried my scope in the horizon. I thought something was amiss. I had been observing the area last week at 10:00 pm. We have beautifully clear skies here, so I will try to image this wannabee double.

    Cheers, Chris.

    • Ach! And I thought it was just because you were too far north!

      That’s what happens when a confirmed star-hopper tangles with a GOTO mount — never fails.

      Thanks for the heads up, Chris. Got it corrected now.

      Must be suffering from a case of uncoordinated coordinates. 🙄

      Hope you get some good shots of that area — I’m cursed with clouds right now.


  2. I just updated the “Planet Posing as a Double Star !!!” post with a sketch and an observation.

    Take a look, and I hope it prompts you to grab a telescope in the next night or two, and really take a look!

    It’s quite a sight.

  3. Love the sketch – and the view – I saw it a couple nights ago after it had passed, but was still within a few minutes of arc and you’re right – very much like Albireo! (Except, of course, if you crank up the power a bit Uranus does show an obvious disc. ) But what I really liked was my view this morning (25th). They were now about six minutes apart and the difference in color contrast was startling. That is, Uranus still had its bluish hue, though less intense, but 44 Piscium had lost a lot of it’s gold. Which is why, when I’m trying to get people to notice star color I always go to a colorful double – the contrast brought about by close proximity sure does wonderful things to the colors we perceive!

    Now – onto Venus and Regulus! I looked at them this morning and they are miles apart. It is hard to believe that by October 3 Venus will close that gap and have a close encounter of the double-star kind! Of course it won’t be as close as this one, and you’ll see the gap widen significantly in just an hour or two – Venus really can move!

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.

%d bloggers like this: