cloudsweeper

6.05pm Monday – clear sky for a change, 8SE Cat with Focal Reducer in action. Aligned on Mars, high, SSE. In for a meal, then:

Comet C/2022 E3(ZTF) – finally got to see it near NGC1647 in Taurus. Faint, grey, fuzzy patch – no colour or tail.

TAURUS DOUBLES

Sigma 559 – matched 7.0 mag pair, 3.1 arcsec apart. Going from x36 to x107 the split was clear, very close, perfect match, stars side-by-side.

Sigma 749 – 6.5 and 6.6 mag pair, 1.15 arcsec. Tight, fairly challenging. I increased the mag gradually to avoid losing the target: x36, 107, 160, 213, 256 – got it! Very close, matched, sec at 11 o’clock. Had to use AV and spot it in moments of good seeing.

Sigma 730 – triple, visual double, another near-matched 6^th mag pair, 9.6 arcsec. Target was below a line of fainter stars. Very nearly a clear split at x36. At x64, the split was good, although still quite close. Matched, sec at 11 o’clock.

Sigma 545 – another triple, visual double, 6^th and 8^th mags, wide 19 arcsec. Good split at x64, fainter sec at 2 o’clock.

Sigma 572 – 7.4 and 7.2 mag pair, 4.5 arcsec. Physical double, not listed in the Cambridge Atlas. At x107 the split was clear, very close match, sec at 12 o’clock.

Very enjoyable 90 minutes. Good to get out there again!

Doug.

LATE TO THE PARTY, BUT FINALLY SAW THE COMET (C/2022 E3(ZTF)!

I've seen so many reports of sightings, and have been keen to catch up, but the skies have been lousy.

Tonight however - good and clear.

I knew that at 7.00pm the comet was 0.5deg west of the open cluster NGC1647 in Taurus, so used GoTo with the 8SE Cat (with Reducer) and landed on the cluster.  The comet was very easy to see, close by.  It was just a small, faint, fuzzy patch - no colour or tail, but great to see anyway.  Bigger and clearer going from x36 to x107.

I called my wife out to share the excitement, since she has heard little else from me for several days.

Went on to take in some Taurus doubles - report elsewhere.

Very satisfying!

Doug.

Billy - Mars can be a bit of a let-down compared with the Moon.  At first, you will probably just see a bright red object, bigger than a star.  With practice, you can make out some shading, or even an ice-cap. Depends on conditions and how close Mars is to Earth.  You can increase the mag and make it a little bit larger and less bright.  Keep trying and practising is the best advice I can give.

Doug.

RILLES IN POSIDONIUS

Quick hour, 5-6pm with the ED80 Triplet looking at the Moon (high, east of south, 1 day to 1st quarter).

Posidonius near terminator.  x120 - inner concentric ridges, central crater, nearby arc of hills (3 or 4 made out).

At x160 I also spotted a small pit and the rilles (Rimae Posidonius) - very faint cracks, seen in AV, coming and going from view.  One was "diagonal", to the east of the central crater, and another parallel one ran near the west side. 

It's good to see these features which are not apparent on first viewing.

Finished with a quick look at Jupiter - Io was crossing the planet's face and was not seen on this occasion.  The STB however was quite clear along with the two more easily seen belts.

Doug.

INSTANT GRS!

Took the ED80 Apo out at 5.15pm - great one-piece set-up - and looking at Jupiter immediately saw the GRS right in the lower middle of the SEB as expected.  Maybe it comes with experience - it took me 2.25 years to see the thing for the first time.

And viewing around twilight is helpful for such targets too.

And that's enough - fingers frozen, in for a tasty beer!

Doug.

Saw this (Ganymede shadow and moon transit) at about 5.15pm when the planet was not too bright.  I've seen shadow transits, but never with the moon as well before now.  Wonderful!

Doug.

Spent the day fiddling with the ED80 triplet to get it (plus finder) on the AZ4 for grab 'n' go.  The fixed dovetail bar is very inconvenient.

So then when I spotted Jupiter (high south) at 5.00pm, I trained said 'scope on it.

At first, only Callisto and Europa were seen, but at x120, I noticed the shadow of Ganymede in the middle of the SEB.  A bit later, Io appeared at the limb, and could clearly be seen moving away from the disc.

Up to x160.  What's that?  Ganymede itself, right where it should be, a distinct pale spot.  My first viewing of a moon transit, fabulous!  And the STB also showed up.  All still sharp at x192.

Best I've seen Jupiter for a long time.  I put it down to a quality apo frac - sharp, no CA - and observing the planet before the sky got very dark.

Mars was also good and sharp, with very clear albedo differences.

Finished with M45 at x27 / 2.77deg - absolutely beautiful in that 'scope.  A great 60 minute session.

Only problem - now I want a 102 Apo!

Doug.

Thursday, 6.00pm, 8SE Cat + Focal Reducer.  Aligned on Mars - worked well, as targets were near the planet.

Sigma 427 - two 7th mag stars, 7.0 arcsec apart - target at the top of a "kite" of stars - going from x36 to x73, got the split, very close, near match, sec at 8 o'clock.

Sigma  435 - 7th and 8th mags, 14 arcsec - target at a corner of an irregular quadrilateral - at x73, the split was very clear, mismatched, sec at 1 o'clock.

Sigma 494 - another 7th mag pair, 5.3 arcsec - at x73 the pair were very close, matched, with the sec at 1 o'clock.

I wanted to go for some tighter examples, but cloud rolled in.  Short, pleasing session anyway!

Doug.

ANOTHER DISAPPEARING MOON!

Thursday, 5.20pm, 8SE Cat + Focal Reducer, Jupiter west of south, aligned on it.

Io was very close to the disc, but I couldn't see it at x36.  At x128 there was a tiny faint dot very close to Jupiter.  Struck me that I would not have spotted this with the 102S Frac I used yesterday on account of the CA around the planet.

At x160, the moon was very clear, just "kissing" the NEB.  I checked the time, and found that seven minutes later it has gone behind Jupiter.  

Well worth seeing, and another example of a very dynamic system, changing before your eyes!

Doug.

Very cold, grass wet, so I quickly set up the short focus 4" frac on the patio. 

Jupiter and three moons on show, then the waxing gibbous Moon.  Nice starfield in Cygnus.  Called my son and two grandsons out for a look.  They were greatly pleased with the views.

Not so much what I saw, rather who was there to share it with!

Doug.

Jupiter’s moons just touching the disc:

# Ganymede going from “contact” to “pimple” then disappearing behind the planet all in 13 minutes. A fascinating, dynamic system!

# Io “kissing” the SEB and casting a shadow on it.

# Io and Callisto in contact with the disc at the same time – Io at the side, Callisto at the top.

Long spiky shadows on the Moon:

# 16 mile shadow from Mount Pico in M. Imbrium.

# 34 mile shadow from Plato’s rim to near its centre.

# 40 mile shadow from Walther’s central peak to the western rim. The longest one so far.

Asteroid Juno - 12^th in size order. Needed AV and higher mag to increase contrast. My fourth asteroid.

14 Ari – one of the nicest doubles of the year. A A bright primary, with a close and matched 8^th mag pair well separated from the primary, all in an attractive field. Wide doubles at low magnification can be most appealing.

I wish all my fellow SGL members many new, interesting, and unexpected observations in 2023!

Doug.

40 MILE SPIKY SHADOW ON MOON

6.00pm, looked good.  10" Dob inaction.  First quarter Moon high, east of south.  Jupiter lower, near south.  Mars high in the east.

Great, off we go.  Crater Walther was near the terminator.  Its central peak cast a spike-like shadow from a little east of centre to the western rim.  Diameter of crater is 128km, so this shadow was at least 64km, which is about 40 miles!

6.15 total cloud.  

Short but sweet!

Doug.

8 hours ago, Epick Crom said:

+1 for Sky Safari Plus! I still use version 6, haven't yet upgraded to version 7. 

It has revolutionised my observing. When I first started serious observing two years ago the upside down and reversed view through my reflector was difficult for my brain to wrap around. The moment I got SS Plus with its capability to match my view, everything became much clearer. Highly recommended!

Joe - I should use my Sky Safari more, I suppose.  I use Stellarium when observing.  I match the EP views with CTRL/Shift/H for a refractor, and both H and V for a reflector.

Doug.

Thanks Paul @wookie1965, that confirms what I concluded!

Doug.

MYSTERY DOUBLE - Is it 65 Psc or 65 And??

65 Psc (Sigma 61) – matched 6th mag pair, 4.4 arcsec separation.  Little else in the field, although it was not very dark!  Going from x36 to x73, got the split – close, perfect match, secondary at 11 o’clock.

This one took a bit of working out!  It is in Haas, but in the Cambridge Atlas, it is given as 65 And. It is right on the boundary of the constellations, and despite the title, it can be classed as a star in Andromeda.  To add to the confusion, its SAO number is 74296, but CDSA and Stellarium have it as 74295.  (Other sources list 65 And as a completely different and non-physical double, with the number 23319.)

I mention this here as the puzzle added extra to the observation.

Full report with four more doubles and other things is in the Observing Doubles section.

Doug.

4.25pm Wednesday, 8SE Cat + Focal Reducer.  Clear sky.  And not as bitterly cold as in recent days!

65 Psc (Sigma 61) – matched 6th mag pair, 4.4 arcsec separation.  Little else in the field, although it was not very dark!  Going from x36 to x73, got the split – close, perfect match, secondary at 11 o’clock.

This one took a bit of working out!  It is in Haas, but in the Cambridge Atlas, it is given as 65 And. It is right on the boundary of the constellations, and despite the title, it can be classed as a star in Andromeda.  To add to the confusion, its SAO number is 74296, but CDSA and Stellarium have it as 74295.  (Other sources list 65 And as a completely different and non-physical double, with the number 23319.)
 
Sigma 3050 And - 6th mag pair, 2.4 arcsec.  Several stars in the x36 FOV.  Got the split at x142.  Very close, good match, sec at 7 o’clock.

Sigma 79 And – quadruple, visible double (2) + (2).  A 6th mag pair again, wider at 7.9 arcsec.  Lovely, busy field.  Split at x73, clear but close, with sec at 8 o’clock.

Sigma 141 And - 8th mag pair, 1.7 arcsec.  Another busy field.  Just got the split at x213 – very close, coming and going with the seeing.  Secondary at 11 o’clock.

Sigma 245 And - 7th and 8th mags, 11 arcsec.  This is a (2) + 1 triple, visual double.  Quite a busy field.  Target is in the middle of a line of three brighter stars.  Clear split at x36, though still very close.  Sec at 11 o’clock.

I also took in Jupiter (two moons either side), Mars (detected some albedo differences), M31 (fuzzy patch, but very clear as usual), and M45 Pleiades cluster.

A very enjoyable hundred minutes, with a bit of a puzzle to solve afterwards!

Doug.

I never liked control via a phone/tablet.

Lat/long - enter manually.  Handset then stores the data.  Next time, just enter time and date.

Alignment - one-star or planetary works fine over a fair range.

Levelling - put a little spirit level on the mount and get it right with small adjustments to two of the legs.

No WiFi, no StarSense, no GPS module (mine broke three times).

Doug.

I was tempted by the crystal clear sky, so set up the 8SE/GoTo and took in Jupiter, which was beautifully sharp at x73, 160.  Fancied some tightish doubles in Perseus,

but I had to pack up after 30 minutes - fingers frozen, ice glistening on the lawn and risk of slipping.  The coldest I've known it since I began this pastime 8 years ago!

Hope it's this clear in a few days when it's meant to get a couple of degrees warmer!

Doug.

4.50pm Weds. - 8SE + Focal Reducer – aligned on Jupiter.

Sigma 219 - 8^th mag unmatched pair, 11.6 arcsec separation – a physical double, not in CDSA. Field sparse x36, except for bright “arrowhead” of stars close by. Got the split at x64 – clear, with fainter secondary at 7 o’clock.

Sigma 285 - 7^th and 8^th mags, 1.7 arcsec. Fairly sparse field at x36, but a line of three nearby stars helped with confirmation. Going straight to x191, I lost the target, so did it in stages: x91, x116, x191- possibly got the split, then on to x213 – very close, fainter star at 7 o’clock in moments of good seeing. Just to be sure, I went up to x256 and had no doubt about the split.

(Sigma 286 – a short hop from the above - should have been easier at 3.0 arcsec, but the sec was only 10^th mag and I believe the rising bright Moon nearby stymied the observation!)

Finished with M31 and the Double Cluster.

A satisfying and somewhat challenging 75 minutes.

Doug.

(OK, back in action - covid cleared up rapidly, although taste and smell still impaired.)

JUPITER GETS DOUBLE KISS

4.15pm Mon. - 102S grab 'n' go frac in action - Moon (3 days to full) low, east.  Quick look at Schickard on terminator.

JUPITER was the only other object in view, lowish, SE.  Europa lay to the west, Ganymede a similar distance to the east.  Where were Io and Callisto?  Behind?  In front?

I upped the mag to x100 and was delighted to see exactly where they were: Io was 'kissing' the disc on the western (in the sky) edge, and the fainter Callisto was doing the same right on the top of Jupiter.  A fine spectacle!  

I finished after 40 minutes as the cloud got thicker.  Would have liked to see the progress of the moons.

It's great how a session often throws up unexpected, interesting, and unusual views!

Doug.

3 hours ago, paulastro said:

It's nice your wife has done this for you Doug.  I hope you have less serious symptoms and you're back at the telescope soon. All the best, Paul

 

 

 

Thanks Paul.  Feeling rough, but it hasn't gone to my chest, so I'm grateful for that!

Targets lined up for next time out.

Doug.

5.50pm Saturday.  Wife just photo'd Moon and Jupiter in a lovely clear sky for me.  

Will I go out in the cold soon to get some action?  Well, no.....I've got covid!!  😷

Doug.

Spur of the moment, one-hour session with the 8SE (with focal reducer, as usual these days) before mealtime:

Waxing crescent Moon, low, near south - nice to see the Earthshine naked eye, then in the EP x36 / 2.03deg of field.

Saturn - a bit higher, to the east; Jupiter higher still, SE.

Having aligned on the Moon, I wasn't sure the GoTo would hit M31.  It did, perfectly!  Large bright fuzz at x53.  Better framed at x36, with many surrounding stars.  Never fails to fascinate.

Even further round, the Double Cluster, and GoTo was spot on with that too.  Beautiful as ever x36 / 2.03deg.

Always good to go for easier, familiar targets!

And so, mealtime (with a slug of red).

Doug.

I had a similar experience with my 8SE.  I hadn't secured it properly in the Celestron mount, and it dropped out.  Luckily, it was near a garden table, so didn't fall far, then - with lightning reactions - I thrust an arm out and stopped it crashing to the ground.

All good.  Still well collimated.  Very, very lucky!

Doug.

For extended objects (e.g. galaxies, planets), exit pupil needs to be between say 2 and 4mm.  Lower, and the object brightness decreases more.

For point objects, brightness is a function of aperture, so they become more noticeable with smaller exit pupil (more mag) i.e. reduced sky brightness.  This is because contrast increases.

Doug.