m1ck Posted March 7, 2012 Share Posted March 7, 2012 lovely clear sky here in the northeast . i know it might sound silly but the moon is full and very bright and have been asked why so bright and being a newbee could'nt give a positive answer . NOT A PROPER ASTRONEMER YET STILL LEARNING. Can u give me a answer. CHEERS . Link to comment Share on other sites More sharing options...
Mr Spock Posted March 7, 2012 Share Posted March 7, 2012 The moon is bright because it receives the same light the Earth does. So, if you can imagine the contrast between night and day on Earth, that is what you are seeing with the moon - the Earth in night time and the moon in daytime. Link to comment Share on other sites More sharing options...
wired2moon Posted March 7, 2012 Share Posted March 7, 2012 Because the sun is directly behind us its light is shining straight onto the face of the moon from our perspective. Even though the moon's surface isn't actually that reflective (just 11% I read somewhere) the sun is just really really bright. Link to comment Share on other sites More sharing options...
iwatkins Posted March 7, 2012 Share Posted March 7, 2012 And thankfully the average moon albedo is only 12%. If it was covered in ice, albedo ~95%, it would very bright indeed. CheersIan Link to comment Share on other sites More sharing options...
m1ck Posted March 7, 2012 Author Share Posted March 7, 2012 CHEERS FOR THAT GUYS. IT MAKES SENSE WHEN U GET YOUR HEAD ROUND IT. blumming BRIGHT TONIGHT . WOTS IT LIKE LOOKIN THROUGH A SCOPE DO U NEED FILTERS? Link to comment Share on other sites More sharing options...
Monki Posted March 7, 2012 Share Posted March 7, 2012 Where in the uk are you? The only reason i ask is because it's not tinted red here in west yorkshire. Are you near or in a city?Sent from a Galaxy S 2 far away. Link to comment Share on other sites More sharing options...
wired2moon Posted March 7, 2012 Share Posted March 7, 2012 Only if you have a sizeable aperture would you need a filter Link to comment Share on other sites More sharing options...
m1ck Posted March 7, 2012 Author Share Posted March 7, 2012 NOT TINTED RED ? I AM LOOKIN FROM SUNNY STOCKTON . GB. LOOKS STUNNING BUT NOT LOOKIN THRO SCOPE JUST YET . JUST EYEBALLING. Link to comment Share on other sites More sharing options...
Monki Posted March 7, 2012 Share Posted March 7, 2012 Wow...for some reason i read your post as "blumming bright red", which is why i said it didn't look red here..haha oh just ignore me it's been a long week and it's only wednesday.. O_oSent from a Galaxy S 2 far away. Link to comment Share on other sites More sharing options...
mallorcasaint Posted March 7, 2012 Share Posted March 7, 2012 You would be advised to use a moon filter as even the light from the moon can damage your eyesight! Link to comment Share on other sites More sharing options...
iwatkins Posted March 7, 2012 Share Posted March 7, 2012 ... No, it cannot. Link to comment Share on other sites More sharing options...
acey Posted March 7, 2012 Share Posted March 7, 2012 Full moon is much more than twice as bright as a half moon (it's about 9 times as bright). This is because of the "opposition effect", with light being reflected straight back towards Earth rather than being seen at an angle.Putting it simply, you could say that at full moon there there are no shadows on the moon's surface, but at half moon there are.Opposition surge - Wikipedia, the free encyclopediaMoonlight can't damage your eyesight, even when looking through a large telescope. But it looks as uncomfortably dazzling as any bright light seen at night, and a filter will make details more apparent. Link to comment Share on other sites More sharing options...
stevetynant Posted March 7, 2012 Share Posted March 7, 2012 I'm not going out in the cold for a while whilst the moon is as bright as it is - its like a huge floodlight up there at the moment Link to comment Share on other sites More sharing options...
patomlin76 Posted March 7, 2012 Share Posted March 7, 2012 Well I braved a bit of observing tonight accompanied by the floodlight it was so bright I could read the skymap easily. Completely washed out sky but still managed to explore some clusters here and there...I didn't know about the relative brightness compared to a half moon, as I was wondering why the sky was so bright.Gave up after an hour as with this moon out you're severely restricted, especially with 5.1in of aperture...Sent from my iPhone using Tapatalk Link to comment Share on other sites More sharing options...
mallorcasaint Posted March 7, 2012 Share Posted March 7, 2012 ... No, it cannot.It may not be permanent but it can certainly temporarily affect your vision. I was on drops for two weeks after a particularly long session viewing with a 5" scope! Even though it is reflected light it can have an effect. Link to comment Share on other sites More sharing options...
gurneyfan67 Posted March 8, 2012 Share Posted March 8, 2012 At full moon I like to use a skyglow or blue filter to increase contrast. It makes the "rayed craters" more visible against the gray background. Also if you are viewing other targets on the same night it helps to avoid the blackout your eyes can experience when observing the full Moon. Link to comment Share on other sites More sharing options...
Daniel-K Posted March 8, 2012 Share Posted March 8, 2012 star clusters are the way to go when moon is to bright for dso's im currently working on a list of star clusters that are bright and are interesting thinking of posting the list as a PDF when im finished for people to use when the moons up currently have about 20 on the list Link to comment Share on other sites More sharing options...
heathenwoods Posted March 8, 2012 Share Posted March 8, 2012 Daniel-K: That's an excellent and generous idea. Nice one. Link to comment Share on other sites More sharing options...
LukeSkywatcher Posted March 8, 2012 Share Posted March 8, 2012 I was just wondering last night about how much light is reflected off of the full moon compared to direct sunlight from the sun during the day. I had a figure of 10% in my head. Nice to know my sponge retained such info as it was yrs ago i read this fact. So its abiut 10-12%. Link to comment Share on other sites More sharing options...
Astro-Nova Posted March 8, 2012 Share Posted March 8, 2012 I only had my scope yesterday, Took it out and looked at the moon, it was bright but I still had no problems what so ever viewing it, the brightness did not do anything. Dont know if it might be where I live but if this is the brightest the moon can get then Id never have to buy a moon filter, I think.... Link to comment Share on other sites More sharing options...
jamespels Posted March 8, 2012 Share Posted March 8, 2012 I was just wondering last night about how much light is reflected off of the full moon compared to direct sunlight from the sun during the day. I had a figure of 10% in my head. Nice to know my sponge retained such info as it was yrs ago i read this fact. So its abiut 10-12%.Hi Paul,not sure if I have read this properly but, just in case, the full moon is not 12% as bright as the sun - what zero-g and iwatkins mean is that it reflects about 12% of the light that falls onto it (it has an albedo of about 12%). Compared with the full moon, the sun is about 400,000 times brighter as viewed from Earth. The table on this page gives some nice apparent magnitude comparisons.Apologies for excessive use of a well-known online encyclopaedia - I am knowlingly relying on data I know may well be wrong without checking it Link to comment Share on other sites More sharing options...
Grunthos Posted March 8, 2012 Share Posted March 8, 2012 Even though it is reflected light it can have an effect.The only effect it will have is to temporarily and without detriment make you lose a bit of night vision for several minutes (hence a reason why some, but not all, astronomers don't like good old shiny Luna in the sky;)).With respect, let us be clear for the benefit of new observers.The moon will not damage eyesight as per the original assertion (obviously if one has a previous eye condition it may affect that to a greater or lesser extent).Many astronomers use a moon (or neutral density) filter or (my preference) a variable moon filter. Some just like a "naked" moon.(PS: M1ck - You are observing, you are learning, you are asking questions and genuinely curious - seems to me that's a good definition of a "proper astronomer"!) Link to comment Share on other sites More sharing options...
Stu Skywatcher Posted March 9, 2012 Share Posted March 9, 2012 Does the brightness of the full moon also increase because when it's full we are getting max surface area reflecting back at us?I was at Albury last night for a couple of hours. Whilst there I got chatting to a really nice guy (Derek, I think), he took a couple of shots of the moon while we were chatting and needed 1/1000 sec shutter speed with ISO 100 film speed, that's like taking a pic of a fast moving object in bright sunlight :eek:. Link to comment Share on other sites More sharing options...
Grunthos Posted March 9, 2012 Share Posted March 9, 2012 Does the brightness of the full moon also increase because when it's full we are getting max surface area reflecting back at us?Yes Link to comment Share on other sites More sharing options...
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