Re: Night Sky : Mon Sep 16, 2013 2:42 am  

MattyB wrote:

http://www.bbc.co.uk/news/science-environment-24026153

Voyager 1 finally leaves the solar system, can't believe a craft launched a full two months prior to "Star Wars: A New Hope" hitting UK cinemas and the fact it travels away from us at 1.4 million km per day is only entering interstellar space around this time!

What I find most amazing is that Voyager I's transmitter only has a power of 22 watts (yes, a quarter of a lightbulb) yet we can pick it up from 11.5 billion miles. But, in fact that's really bright when compared to most things radio telescopes study.

The signal, at 186,000 miles per second, takes around 17 hours to arrive back at Earth.

By the time it first arrived at Neptune, Voager I's fuel economy from Earth to Neptune averaged around 30,000 miles per gallon.

It is not leaving the solar system any time soon, though; that all depends on how you define it, but it is going to be a long while yet. The official Voyager site explains that one opinion is that the boundary is where the Sun’s gravity no longer dominates – a point beyond the planets and beyond the Oort Cloud. This boundary is roughly about halfway to the nearest star, Proxima Centauri. Travelling at over 35,000 mph, it will take Voyager nearly 40,000 years, and it will have travelled a distance of about two light years to reach that point.

It is however on the point of entering interstellar space, that is, crossing the heliopause.

But we will lose comms around 2025.

Re: Night Sky : Mon Sep 16, 2013 8:17 am  

cheers FA.

Re: Night Sky : Thu Oct 17, 2013 4:26 pm  

Well, the contender for "Comet of the Centtury", Comet ISON, is almost here, and brightening nicely. If it continues at this rate, it might even be visible in daylight in late November and might be the brightest object in the night sky between Nov-Jan. That would be cool. it is only magnitude 10 at the moment (naked eye visibility starts around magnitude 6) but it is already easily found with small telescopes. If you want to keep up-to-date there's a page http://www.cometison2013.co.uk/here with all the latest info, images etc. Those who've downloaded the excellent free desktop planetarium software Stellarium can download the comet's details and auto find where it is at any given time. You can also follow @cometison2013. It's accelerated to over 80,000 mph now but will whizz by the Sun at approaching 1 million mph And ISON will be around so many weeks, the good news is that it can't be clouded over on every single night. Can it? Comet ISON by Jeremy Hunt. 4 x 5min exp's at ISO800. Canon 300D / William Optics ZS80, 0.8x reducer / EQ6 Pro. 10 Oct

Well, the contender for "Comet of the Centtury", Comet ISON, is almost here, and brightening nicely. If it continues at this rate, it might even be visible in daylight in late November and might be the brightest object in the night sky between Nov-Jan. That would be cool. it is only magnitude 10 at the moment (naked eye visibility starts around magnitude 6) but it is already easily found with small telescopes. If you want to keep up-to-date there's a page http://www.cometison2013.co.uk/here with all the latest info, images etc. Those who've downloaded the excellent free desktop planetarium software Stellarium can download the comet's details and auto find where it is at any given time. You can also follow @cometison2013. It's accelerated to over 80,000 mph now but will whizz by the Sun at approaching 1 million mph And ISON will be around so many weeks, the good news is that it can't be clouded over on every single night. Can it? Comet ISON by Jeremy Hunt. 4 x 5min exp's at ISO800. Canon 300D / William Optics ZS80, 0.8x reducer / EQ6 Pro. 10 Oct

Re: Night Sky : Wed Oct 23, 2013 12:56 am  

Comet Ison - it's green

Re: Night Sky : Thu Oct 24, 2013 6:00 pm  

Google sky map app, just aim your phone at the night sky to see what you're looking at.

Re: Night Sky : Fri Oct 25, 2013 1:19 pm  

GraftonRed wrote:

Google sky map app, just aim your phone at the night sky to see what you're looking at.

I prefer Night Sky 2, it has a better 'look and feel' and some excellent features, such as sky viewing, visibility, moon and weather forecasts for your specific location for a week in advance, a monthly summary,But these sort of apps are an excellent resource for the casual observer.

Another great app is GoISSWatch, which tracks the movements of the International Space Station and gives you full info on when you can next see it (tonight around 18:35 if you have a clear sky)

Re: Night Sky : Mon Oct 28, 2013 1:37 am  

And now astronomers have broken the record for the most distant galaxy yet found - it's z8_GND_5296 and it is 30 billion light years away. That is 176,354,994,510,000,000,000 miles (176 quintillion) http://www.bbc.co.uk/news/science-environment-24637890

And now astronomers have broken the record for the most distant galaxy yet found - it's z8_GND_5296 and it is 30 billion light years away. That is 176,354,994,510,000,000,000 miles (176 quintillion) http://www.bbc.co.uk/news/science-environment-24637890

Re: Night Sky : Wed Nov 13, 2013 1:28 pm  

One of the loveliest, and most thought-provoking space images ever taken http://www.jpl.nasa.gov/spaceimages/det ... d=PIA17172 http://www.bbc.co.uk/news/science-environment-24913141 Earth/moon is the tiny blue dot just below bottom right of the planet, as in this detail

One of the loveliest, and most thought-provoking space images ever taken http://www.jpl.nasa.gov/spaceimages/det ... d=PIA17172 http://www.bbc.co.uk/news/science-environment-24913141 Earth/moon is the tiny blue dot just below bottom right of the planet, as in this detail

Re: Night Sky : Thu Nov 28, 2013 3:45 pm  

Does anyone have any experience / thoughts / to offer about this, please … https://www.aldi.co.uk/en/specialbuys/thursday-28th-november/product-detail/ps/p/dobson-telescope/ ETA: I've just seen and understood FA's detailed answer to Cornish's question in another thread about a Lidl scope and although the one I asked about is from Aldi and looks different, I'm sure that FA's points are generic. But, just out of curiosity, I'd still appreciate info on my supplementary question ... Also, will it interface with a DSLR? If so, how?

Does anyone have any experience / thoughts / to offer about this, please … https://www.aldi.co.uk/en/specialbuys/thursday-28th-november/product-detail/ps/p/dobson-telescope/ ETA: I've just seen and understood FA's detailed answer to Cornish's question in another thread about a Lidl scope and although the one I asked about is from Aldi and looks different, I'm sure that FA's points are generic. But, just out of curiosity, I'd still appreciate info on my supplementary question ... Also, will it interface with a DSLR? If so, how?

Re: Night Sky : Fri Nov 29, 2013 12:45 am  

LeedsBornWelshRoots wrote: Does anyone have any experience / thoughts / to offer about this, please … https://www.aldi.co.uk/en/specialbuys/thursday-28th-november/product-detail/ps/p/dobson-telescope/ ETA: I've just seen and understood FA's detailed answer to Cornish's question in another thread about a Lidl scope and although the one I asked about is from Aldi and looks different, I'm sure that FA's points are generic. But, just out of curiosity, I'd still appreciate info on my supplementary question ... Also, will it interface with a DSLR? If so, how? That scope looks an utter waste of time. A Dobsonian is what is called in the trade a light bucket, that is, a comparatively huge looking scope which works well due to the sheer size of its mirror. They present a way to have an enormous powerful scope which is very portable, very quick to assemble and thus loads of bang for your buck. This item says it has a "lens diameter" of 76mm - I presume they don't know any better as a Dobsonian doesn't have an objective lens. But 76mm is tiny, a light pinhole rather than a bucket, and so there is no point to it. Dobsonians mostly use a simple alt-azimuth mounting (that is, the base rotates around the horizontal and the scope pivots up and down) and most (certainly not this one) do not have any form of tracking or guidance system, the reason being that they let in so much light and have a comparatively large field of view, so you don't need to move the scope that much. But the lack of tracking makes even a proper Dob pretty useless for astrophotography (not that it can't be done; but is very much a specialist area with a proper Dob)

LeedsBornWelshRoots wrote: Does anyone have any experience / thoughts / to offer about this, please … https://www.aldi.co.uk/en/specialbuys/thursday-28th-november/product-detail/ps/p/dobson-telescope/ ETA: I've just seen and understood FA's detailed answer to Cornish's question in another thread about a Lidl scope and although the one I asked about is from Aldi and looks different, I'm sure that FA's points are generic. But, just out of curiosity, I'd still appreciate info on my supplementary question ... Also, will it interface with a DSLR? If so, how? That scope looks an utter waste of time. A Dobsonian is what is called in the trade a light bucket, that is, a comparatively huge looking scope which works well due to the sheer size of its mirror. They present a way to have an enormous powerful scope which is very portable, very quick to assemble and thus loads of bang for your buck. This item says it has a "lens diameter" of 76mm - I presume they don't know any better as a Dobsonian doesn't have an objective lens. But 76mm is tiny, a light pinhole rather than a bucket, and so there is no point to it. Dobsonians mostly use a simple alt-azimuth mounting (that is, the base rotates around the horizontal and the scope pivots up and down) and most (certainly not this one) do not have any form of tracking or guidance system, the reason being that they let in so much light and have a comparatively large field of view, so you don't need to move the scope that much. But the lack of tracking makes even a proper Dob pretty useless for astrophotography (not that it can't be done; but is very much a specialist area with a proper Dob)