Ring nebula white dwarf

[Starfleet]

I’m thinking if the white dwarf in the middle of the Ring Nebula could be seen with a 10 inch dobsonian? I can spot the nebula easily through a six inch, but I haven’t managed to lug my 10 inch out yet. Then there is also the Crab nebula pulsar that is suppose to flash at visual wavelengths. Ha ha ha seeing that really would be an ambition!

Anyone here seen either?

[RobH]

I've seen the WD in the ring neb from a very dark site, with totally dark adapted vision, through my old 10 inch LX200.

Cheers

Rob

[narrowbandpaul]

the crab pulsar flashes every 1/33 of a second. The reaction time for a human is around 0.1 seconds, so the flash shouldnt be observable, sorry

[Starfleet]

Rob, thats really encourageing. I would need to find a dark site but that wont be easy in the UK. Phtographing the WD should be easier so I'll see if i can do it next summer.

The secondary of Sirius B is another WD; probably just as harder to see with a 10 inch dob.

The crab pulsar, well I wouldn't expect to see it blink, i was just hoping to see it full stop. It would be an ambition still

[narrowbandpaul]

hmmm... you might see it...prob need large aperture high mag and good seeing.

[Moonhawk]

the crab pulsar flashes every 1/33 of a second. The reaction time for a human is around 0.1 seconds, so the flash shouldnt be observable, sorry

Is this a function of dark vision - because the flicker of a TV running at 50hz is noticeable to the extent that it can be uncomfortable for some people to watch.

[narrowbandpaul]

well if 50hz is detectable then the crab might be too

[lunator]

Rob, thats really encourageing. I would need to find a dark site but that wont be easy in the UK. Phtographing the WD should be easier so I'll see if i can do it next summer.

The secondary of Sirius B is another WD; probably just as harder to see with a 10 inch dob.

The crab pulsar, well I wouldn't expect to see it blink, i was just hoping to see it full stop. It would be an ambition still

The Pup should be visible this year from the UK. It will require moderate magnification but very stable seeing.

[Merlin66]

My mate Dennis took some wonderfull images of the pup ( Sirius earlier this month.

http://www.iceinspace.com.au/forum/showthread.php?t=37689&page=2

He used a Mewlon 180, x4 Powermate and a DMK31; exposures from 1/5 to 1/15sec.

[lunator]

Very nice pics.

The issue for most of us is that the lack of height of Sirius acheives from the UK.

Cheers

Ian

[Lady Isabella]

Just a suggestion regarding the Crab nebula, not really sure how well it will work, but forty years ago Joe Wampler at Lick observatory used a rotating shutter just in front of the focal plane of the telescope to capture the pulse of the star. The frequency of the rotating shutter was slightly different from that of the Pulsar, the result was to slow down the frequency of the pulsation, enabling it to be captured by a television camera.

Amateurs now have some superb imaging kit at their disposal, and I wonder if an amateur with a large scope could use the same technique to capture the on-off blink of the pulsar?

Might make a nice project for an Astro club or an individual with the right kit.

[lunator]

I was reading through my copy of Ian Ridpath's observing book 'Collins guise to Stars & Planets' and it does say in there that the pulsar has been seen to flash visually but it does not say what scope was used etc.

Cheers

Ian