Bright Nova

[Guest]

Anyone interested in Astronomy will be interested in a Nova which erupted on August 14th, and which has now reached naked-eye visibility (at least if you do not have a lot of light pollution), and it is easily visible in binoculars, high in the sky all night. This is in the top 30 brightest novae in recorded history, most of them are much fainter, so worth having a look. It is hard to say how long it will remain bright as some fade rapidly but others fade more slowly, but it should be easy to find for several days.

http://www.skyandtelescope.com/observing/highlights/Bright-Nova-in-Delphinus-219631281.html

https:////http://www.universetoday.c...th-binoculars/

[Anna]

Thanks for that but cloud cover will probably mean no sighting here (and I missed out on seeing the Perseid), here's the National Maritime Museum blog with how to see it in the UK

http://blogs.rmg.co.uk/rog/2013/08/16/find-a-nova-in-delphinus/

[Roehre]

Thanks Pikaia, it escaped my attention so far.
So, not likely to become a new crab nebula then (the 1054 nova)
Not too far from the 1918 nova (at the other side of Altair (at the border of, but still in Aquila))

[Pikaia]

Thanks Pikaia, it escaped my attention so far.
So, not likely to become a new crab nebula then (the 1054 nova)
Not too far from the 1918 nova (at the other side of Altair (at the border of, but still in Aquila))

It was a SUPERnova in 1054, not a nova. When we get the next supernova in our galaxy it will be extremely bright and it will be a big news story, unlike this nova, which I have not seen reported on any news outlet.

[LeMartinPecheur]

We are said to be statistically well overdue (like a few hundred years IIRC) for a visible supernova in our own galaxy, and I'd certainly love to see one. If I don't get one in my lifetime I'll blame the government of course

[BBMmk2]

It was quite cloudy our way, so would have not been able to see anything. Just like when we had that meteor shower.

[Roehre]

It was a SUPERnova in 1054, not a nova. When we get the next supernova in our galaxy it will be extremely bright and it will be a big news story, unlike this nova, which I have not seen reported on any news outlet.

As far as i am aware a supernova is only an extraordinarily big nova, nothing else

[ferneyhoughgeliebte]

As far as i am aware a supernova is only an extraordinarily big nova, nothing else

No champagne involved?

[LeMartinPecheur]

As far as i am aware a supernova is only an extraordinarily big nova, nothing else

My impression is that while some supernovas come about through the same mechanism as (some?) novas - accretion of material by a white dwarf from a companion star - there is a difference in kind. Supernovas are the only way to generate the heaviest elements (heavier than lead), and do this because it is a very much bigger bang (for your buck?). Therefore there is also a massive difference in the total energy output (most of it not visible light) too. Can someone clever put some numbers on the scale of this difference please?

[Stillhomewardbound]

I'd love to catch that but being a Londonist (Blackheath, South East London) we suffer from but awful light pollution. Just recently EDF have replaced the street lights in the area of the heath and it now looks like a football ground with the skies illuminated for miles around.

Fair enough, good street lighting makes road conditions safer but can these lights not have been fitted with appropriated visors to restrict the spread of light upwards. It's a 'no brainer' to me, as they say.

[Roehre]

....Fair enough, good street lighting makes road conditions safer but can these lights not have been fitted with appropriated visors to restrict the spread of light upwards. It's a 'no brainer' to me, as they say.

Off Topic, but nevertheless....
There is strong evidence that this relation "brighter=safer" is not as straight forward as it seems at first thought .
One of the strongest counter arguments is a comparison between the accident frequence on Belgian Motorways compared to those of Britain, the Netherlands, northern France or Rhineland-Westfalia in Germany. There is no difference, to the contrary, the figures for the Belgian roads are slightly higher than those for the bordering countries, although all the Belgian motorways are illuminated by streetlights. Research in the Netherlands shows that trunk roads which are not carrying streetlights but for level crossings are as safe as, if not safer than, completely illuminated ones. One of the reasons: Especially car drivers tend to drive faster in illuminated areas - they feel more in control.

[Belgrove]

...Can someone clever put some numbers on the scale of this difference please?

The standard unit for the energy output of a 'type 1' supernova is 10^51 ergs, abbreviated as 1 foe ("51-ergs"). By contrast, a typical nova's energy output is about 10^(-12) foe. A supernova caused by gravitational collapse rather than an accretion event emits 100 foe. The scale of these numbers can be appreciated by noting that the sun throughout its entire lifetime of about 10 billion years emits about 1.2 foe. The nova and supernova events occur on the timescale of days or hours. The universe is an awesome place.

[amateur51]

The standard unit for the energy output of a 'type 1' supernova is 10^51 ergs, abbreviated as 1 foe ("51-ergs"). By contrast, a typical nova's energy output is about 10^(-12) foe. A supernova caused by gravitational collapse rather than an accretion event emits 100 foe. The scale of these numbers can be appreciated by noting that the sun throughout its entire lifetime of about 10 billion years emits about 1.2 foe. The nova and supernova events occur on the timescale of days or hours. The universe is an awesome place.

Many thanks for those comparisons, Belgrove.

Totally boggling

[Roehre]

Many thanks for those comparisons, Belgrove.

seconded

[Dave2002]

Fair enough, good street lighting makes road conditions safer but can these lights not have been fitted with appropriated visors to restrict the spread of light upwards. It's a 'no brainer' to me, as they say.

it shpuld be possible to restrict the light going up, and also to increase the output going downwards by reflectiom. Thoe who plan these things, like so many others in our siciety, clearly have no brains - very limited ones, anyway!

In Bucks there was a nice bit of road which then developed street lights. I suggested at the time that they were not a good idea, and spoiled the landscape amongst other things. Years later most of them have been switched off.