Gfamily

Aldi recently had a garden based "middle aisle" promotion that included this garden bag for about £4.

You might find one still available

17 hours ago, Relpet said:

It may just be a matter of timing.  It was a pure fluke that I took the shots when I did and possibly just as the sun was at the optimum angle.  It may never happen to me again!

I'm the same, I posted the pic to our club's FB group and another member had been away with the Macc Astro crowd and had the V and the X pointed out, so it was only when she told me what I'd captured... 

I think there's a few hours when they're visible.

If the rest of the series is as good as Episode 1, this will be fantastic. 

https://www.bbc.co.uk/programmes/w3csz4dk

Presented by Kevin Fong it uses a lot of the audio archives as well as new interviews.

Episode 1 includes contributions from 

Michael Collins, Steve Bales, Margaret Hamilton, James Lovell, Charlie Duke  - not a bad list. 

Can be listened to online, via the BBC Sounds app, or via your usual Podcast app.

Looks like I got the L as well...

Not as well as you though.  

On 08/05/2019 at 23:04, Snooze said:

I have no problem with my Polar Illuminator. It's bright enough for me to see the reticle clearly. The only thing I have with mine is that is does not stay in place even with the adaptor I received(too loose).

I bought a 3D printed adapter on ebay, which works much better than the appalling sw one, which seems to be made from the wrong sort of plastic,  and being made slightly too large doesn't help. 

SynScanInit app is a quick and easy way of making sure your location and time/date are as accurate and correctly formatted as possible. 

HTH

A friend has enjoyed developing his processing skills with Hubble Archive data - he's just processed a fantastic rendition of M51 & NGC5195

4 hours ago, Paul M said:

Sticking with the specifics of telephone apps, it's my understanding that the Stellarium Android app (don't know about iOS) is separate from the Windows Stellarium package. The development of the app was taken over a long time ago by other persons and it evolved separately. I'm not sure if it even exists on Android now but last time I tried it it was a shadow of the Windows version.

Yes, the Android port is separate from the Windows, but it is still being maintained, with its last update in March 2019.

It's all down to preferences of course, and sometimes I like the way that SkySafari clears details from the screen as you zoom out, so as to keep it relatively uncluttered; but at other times I want more detail on the screen - specifically to avoid having to zoom in to find what you're looking for. 

If you're happy with SkySafari, that's fine; but Stellarium isn't to be written off by any means. 

Am I the only one who knows that SkySafari is probably better, but always goes to Stellarium first?

However, for planning purposes, I'd like to suggest DSO Planner to people who haven't tried it.

It's not a 'point at the sky' app, but it allows you to create observation lists, gives you fairly detailed notes and images, a very good sky chart, and the capability to add your own observing notes, whether by keying in the text, or by making a voice recording - being able to keep your eye to the eyepiece and say what you're seeing is invaluable.

The are several versions available (for Android) with different levels of catalogues included, and added features as you go up the versions.

There's a free version that I'd thoroughly recommend people try out.

I've bought the 3rd level version (I think) that takes about 500mb, but is fine on my tablet.

The full online OED has it as an originally Astronautical usage - earliest citation from 1961

Quote

6. orig. and chiefly Astronautics. Functioning acceptably, normal.

1961   M. Savage Launch Vehicle Handbk. (NASA) A-2   For nominal flights, the pitch gyro of the Scout will be torqued at rates which will produce a zero lift.

1966   Aviation Week & Space Technol. 5 Dec. 30/1   The mission is to launch the 800-lb. Prime vehicle to effect a nominal re-entry at 400,000 ft. following injection at 26,000 fps.

1982   M. Leapman Yankee Doodles iii. 177   During the flight, nominal was the word used most frequently. It appeared to mean normal, or within the nominated guide lines (parameters). ‘That's nominal’ meant ‘no problem’.

1994   H. Weinstein Better Man xi. 108   At the time of our departure for the Enterprise, all readings were nominal.

13 hours ago, Space Oddities said:

Apparently, this also started a bit of a rather unhealthy discussion on the Internet. The MIT shared the pictures of this PhD student, and they went viral, as you know. Sadly though, she was pushed to the front seat by most medias as the person without which nothing would have happened, at the expense of the other project members (and there were quite a few!). There were some complaints on social networks, saying her work was as important as other people. Apparently, the MIT simply wanted to promote the work of one of their brilliant students, but also because she's a young woman.

It's sad to see that achieving this amazing result also triggers this kind of discussions... Though I can also understand the anonymous project members, who were certainly as worthy as Katie Bouman. But nobody can be blamed because a picture went viral on the Internet.

At least, the positive side is indeed that it may inspire younger people to work for "space stuff". There is so much left to discover, and the recent progress we made in computer science is going to open new doors. The next decades will be fascinating!

But she's not a student - she was awarded her doctorate in 2017, and has just been appointed as associate professor at Caltech. 

10 minutes ago, bokchoy ninja said:

I suppose you're right, but I just don't want to waste money on a lens that I can't manage (despite being inexpensive). Any issue with a bargain lens that doesn't have ED glass? I'm thinking of, for example:

https://www.keh.com/shop/nikon-200mm-f-4-micro-if-ai-manual-focus-lens-52.html

Thanks!

I'm mostly a Pentax user, so am not really able to talk about other brands; however, I'd say I'd start by checking all the reviews you can find and check out how much CA the lens demonstrates to users. 

As you've identified, there's no need for a lot of the features of modern lenses; so no need for AF* or IS - all you need is a manual aperture ring and good glass. Does that one have manual Aperture? 

* though it seems that AF can be useful for some brands where you can use laptops to measure and adjust the quality of focus via USB cable.

15 minutes ago, bokchoy ninja said:

Howdy, is this thread still active?

I'm curious if anyone can recommend a longer focal length for my nikon aps-c sensor dslr to image DSOs. At the moment my longest lens is 85mm. I'm considerting picking up a "bargain" manual focus 300mm f4.5 for a couple hundred bucks. Would this be a good choice, or a bit too long?

I think most people would say it's a bit long, and you can probably get an 'old glass' 200mm f/4 lens for less, but if you have a well adjusted polar scope and are good at getting alignment with your SA, there's no reason why not to try it. 

I did a talk to my local AS about how Bessel measured the parallax of 61 Cygni - which was done using a telescope where the 6" objective was split, with half on a micrometer thread to allow the distance between the 'nearby' star and a distant star to be measured.

Of course, he measured the separation between 61 Cyg and two other stars over a year,

and from this (despite what looks like a dodgy measurement in Jan 1838), you can see the annual change in parallax

On 11/04/2019 at 23:59, alright1234 said:

θ = A/B = (2.99 x 10¹¹ m) / (4 x 10¹⁶ meters) = 7.475 x 10^-6 degrees or 0.027 arcsec....................80

Ah, you've missed the conversion between Radians (which is what A/B gives - technically it's sin-1 (A/B), and degrees. 

Multiply by 180/pi and you get the right value of just over 1.5 arc seconds for 4.22 ly. 

ETA

parallax itself is defined as the half angle, where 'A' is the earth's orbital radius rather than diameter

Mid Cheshire Astronomical Group

A friend has just this month been diagnosed as having a lack of alignment in her eyes, and has never really been able to see the 3D effect naturally - so 3D images (whether done with red-cyan anaglyph viewer or with a 'Viewmaster" type viewer) have never worked for her. 

As I said, she has finally got a diagnosis - and this week was given an anaglyph image to look at using a correcting prism and she finally saw the full 3D effect.  

At one point, one of the people she saw said "Because of your age, and because you've never had 3D vision, your brain is probably not going to be up to seeing the effect", so she was delighted when it worked for her. 

A Celestron NexYZ smartphone adapter (belated Christmas present from our daughter). 

Very impressed at how well it allows the phone to be accurately positioned.

Much better than the £2.99 one that needs 2 pairs of hands to centre

To be even more chilled, go out and observe naked, aye! 

DSO Planner is a fine piece of software - I particularly appreciate that you can make audio notes against observation list objects,  so you can sit at the eyepiece and talk into it, describing what you can see without having to take your eye away from the eyepiece.

It would be great if there was a way of taking the recording when you were back home with wifi, and porting the audio file into the speech recognition process, to get a transcript. 

There are methods of polar aligning using Drift alignment, which you perform in two steps, observing a star move along a reticle eyepiece to confirm that the mount is correctly aligned N/S and for the correct latitude. If you can set your latitude correctly (using the location where you CAN see Polaris), you could mark out where your tripod legs go at the other site to give you a "near enough" position to do the drift align. (Caveat... I've never tried it, so I don't know how easy it is in practice)

http://www.iankingimaging.com/show_article.php?id=11

Alternatively, How sloped is the lawn in between them? Might you be able to place 2 small paving slabs on the lower side of the slope and a third in a shallow hole up the slope so that you can set your tripod level (or alternatively, just shorten that that leg). 

St Andrews University claims to have the largest 'operational' telescope at 94cm

https://www.st-andrews.ac.uk/physics/pandaweb/newtour/teachf/obs.htm

First copy of my '5 for £5' Sky at Night magazine

plus my first copy of Popular Astronomy since joining the Society for Popular Astronomy.

Both arrived today. 

Hint for levelling (if the built-in level is true), but you don't have a level observing site. 

Set the tripod up and physically turn it about until the bubble lines up with one off the legs. Them shorten that leg until the bubble is centred.

If you're not sure whether the built-in level is true,  find some flat ground,  get the bubble centred (is likely to need  adjusting 2 legs), then rotate the tripod 180 degrees about its axis.

If the bubble stays centred, then it's true. 

27 minutes ago, Viktiste said:

Ok, Thanks for the explanation guys. I got it. I guess the divisions  and lack of labels in PolarFinder got me confused. I  was planning to set up and properly polar align tonight, but then the clouds came sneaking across the sky...

best of luck for tomorrow then.