"He's your son!!" of APOD
- daveboling
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Omega Sunrise
I teleported home one night
With Ron and Sid and Meg.
Ron stole Meggie's heart away
And I got Sidney's leg.
-- Douglas Adams
'Bundinn er bátlaus maðu'.
With Ron and Sid and Meg.
Ron stole Meggie's heart away
And I got Sidney's leg.
-- Douglas Adams
'Bundinn er bátlaus maðu'.
- daveboling
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Equinox in the Sky
I teleported home one night
With Ron and Sid and Meg.
Ron stole Meggie's heart away
And I got Sidney's leg.
-- Douglas Adams
'Bundinn er bátlaus maðu'.
With Ron and Sid and Meg.
Ron stole Meggie's heart away
And I got Sidney's leg.
-- Douglas Adams
'Bundinn er bátlaus maðu'.
- daveboling
- Posts: 4910
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ISS Transits Mars
I teleported home one night
With Ron and Sid and Meg.
Ron stole Meggie's heart away
And I got Sidney's leg.
-- Douglas Adams
'Bundinn er bátlaus maðu'.
With Ron and Sid and Meg.
Ron stole Meggie's heart away
And I got Sidney's leg.
-- Douglas Adams
'Bundinn er bátlaus maðu'.
- daveboling
- Posts: 4910
- Joined: Sun Feb 17, 2002 6:00 pm
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Enceladus in Infrared
I teleported home one night
With Ron and Sid and Meg.
Ron stole Meggie's heart away
And I got Sidney's leg.
-- Douglas Adams
'Bundinn er bátlaus maðu'.
With Ron and Sid and Meg.
Ron stole Meggie's heart away
And I got Sidney's leg.
-- Douglas Adams
'Bundinn er bátlaus maðu'.
- daveboling
- Posts: 4910
- Joined: Sun Feb 17, 2002 6:00 pm
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Moon over Andromeda
I teleported home one night
With Ron and Sid and Meg.
Ron stole Meggie's heart away
And I got Sidney's leg.
-- Douglas Adams
'Bundinn er bátlaus maðu'.
With Ron and Sid and Meg.
Ron stole Meggie's heart away
And I got Sidney's leg.
-- Douglas Adams
'Bundinn er bátlaus maðu'.
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Re: "He's your son!!" of APOD
Can I take this opportunity to ask why astronomical photos so rarely indicate the angular field of view? Is it because the target audience is comprised mainly of people who already know 'how big' things are and those who don't care?
- daveboling
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Re: "He's your son!!" of APOD
For many of the images posted, the angular field of view is fractions of arc seconds. It doesn't mean much, and astronomers don't commonly use, angular field if it would read 1.3E-5 arc seconds for a galaxy cluster. A good number of the APOD descriptions will give angular field of view for larger objects, particularly those that are faint to the naked (can I say naked on this forum ) eye. Even Jupiter (and Saturn, both of which are currently prominent in the night sky), as large as it appears, ranges only from 29.8 to 50.1 arc seconds. So, at best, it would take ~72 Jupiter diameters to make one degree in the night sky. If I remember correctly (long odds here), a fist held at arms length is about 10 degrees (could be 15, don't clearly remember), so holding your fist out next to an object in the sky will allow you to "ballpark" the angular field of view.
Does this help or confuse (hint, I'm better at the latter than the former....)?
dave boling
Does this help or confuse (hint, I'm better at the latter than the former....)?
dave boling
I teleported home one night
With Ron and Sid and Meg.
Ron stole Meggie's heart away
And I got Sidney's leg.
-- Douglas Adams
'Bundinn er bátlaus maðu'.
With Ron and Sid and Meg.
Ron stole Meggie's heart away
And I got Sidney's leg.
-- Douglas Adams
'Bundinn er bátlaus maðu'.
- daveboling
- Posts: 4910
- Joined: Sun Feb 17, 2002 6:00 pm
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Moon Pairs and the Synodic Month
I teleported home one night
With Ron and Sid and Meg.
Ron stole Meggie's heart away
And I got Sidney's leg.
-- Douglas Adams
'Bundinn er bátlaus maðu'.
With Ron and Sid and Meg.
Ron stole Meggie's heart away
And I got Sidney's leg.
-- Douglas Adams
'Bundinn er bátlaus maðu'.
- daveboling
- Posts: 4910
- Joined: Sun Feb 17, 2002 6:00 pm
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Lightning over Colorado
I teleported home one night
With Ron and Sid and Meg.
Ron stole Meggie's heart away
And I got Sidney's leg.
-- Douglas Adams
'Bundinn er bátlaus maðu'.
With Ron and Sid and Meg.
Ron stole Meggie's heart away
And I got Sidney's leg.
-- Douglas Adams
'Bundinn er bátlaus maðu'.
- daveboling
- Posts: 4910
- Joined: Sun Feb 17, 2002 6:00 pm
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Filaments of the Cygnus Loop
I teleported home one night
With Ron and Sid and Meg.
Ron stole Meggie's heart away
And I got Sidney's leg.
-- Douglas Adams
'Bundinn er bátlaus maðu'.
With Ron and Sid and Meg.
Ron stole Meggie's heart away
And I got Sidney's leg.
-- Douglas Adams
'Bundinn er bátlaus maðu'.
- daveboling
- Posts: 4910
- Joined: Sun Feb 17, 2002 6:00 pm
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GW Orionis: A Star System with Tilted Rings
APOD video
dave boling
dave boling
I teleported home one night
With Ron and Sid and Meg.
Ron stole Meggie's heart away
And I got Sidney's leg.
-- Douglas Adams
'Bundinn er bátlaus maðu'.
With Ron and Sid and Meg.
Ron stole Meggie's heart away
And I got Sidney's leg.
-- Douglas Adams
'Bundinn er bátlaus maðu'.
- daveboling
- Posts: 4910
- Joined: Sun Feb 17, 2002 6:00 pm
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- Please enter the next number in sequence: 8
- Location: Huntsville, AL
Sonified: Eagle Nebula Pillars
Yet another APOD video
dave boling
dave boling
I teleported home one night
With Ron and Sid and Meg.
Ron stole Meggie's heart away
And I got Sidney's leg.
-- Douglas Adams
'Bundinn er bátlaus maðu'.
With Ron and Sid and Meg.
Ron stole Meggie's heart away
And I got Sidney's leg.
-- Douglas Adams
'Bundinn er bátlaus maðu'.
-
- Posts: 1735
- Joined: Mon Aug 13, 2007 2:04 am
- Please enter the next number in sequence: 1
- Location: Mercia
Re: "He's your son!!" of APOD
Thanks. It's a question I had been thinking of asking on this thread for years. I guess what I actually like to know is what the angular diameter of the things I am being shown. I asked about angular field of view as that seems analogous to a map scale - which by convention is always there to help us tell if we are looking at a contour map of a mountain or a molehill. The trouble with space is that it looks much the same however much we enlarge it. I posted prompted by the Andromeda galaxy image because there we were given a sense of scale. Without the moon it could have been like a picture from Hubble of a speck of light or less to the naked eye rather than something that is actually quite 'big in the sky' but not seen like that without a little image processing.daveboling wrote:For many of the images posted, the angular field of view is fractions of arc seconds. It doesn't mean much, and astronomers don't commonly use, angular field if it would read 1.3E-5 arc seconds for a galaxy cluster. A good number of the APOD descriptions will give angular field of view for larger objects, particularly those that are faint to the naked (can I say naked on this forum ) eye. Even Jupiter (and Saturn, both of which are currently prominent in the night sky), as large as it appears, ranges only from 29.8 to 50.1 arc seconds. So, at best, it would take ~72 Jupiter diameters to make one degree in the night sky. If I remember correctly (long odds here), a fist held at arms length is about 10 degrees (could be 15, don't clearly remember), so holding your fist out next to an object in the sky will allow you to "ballpark" the angular field of view.
Does this help or confuse (hint, I'm better at the latter than the former....)?
dave boling
I guess unless one is an astronomer then for most of us it's just awesome eye candy.
- daveboling
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Solis Lacus: The Eye of Mars
I teleported home one night
With Ron and Sid and Meg.
Ron stole Meggie's heart away
And I got Sidney's leg.
-- Douglas Adams
'Bundinn er bátlaus maðu'.
With Ron and Sid and Meg.
Ron stole Meggie's heart away
And I got Sidney's leg.
-- Douglas Adams
'Bundinn er bátlaus maðu'.
- daveboling
- Posts: 4910
- Joined: Sun Feb 17, 2002 6:00 pm
- antispam: No
- Please enter the next number in sequence: 8
- Location: Huntsville, AL
Biking to the Moon
I teleported home one night
With Ron and Sid and Meg.
Ron stole Meggie's heart away
And I got Sidney's leg.
-- Douglas Adams
'Bundinn er bátlaus maðu'.
With Ron and Sid and Meg.
Ron stole Meggie's heart away
And I got Sidney's leg.
-- Douglas Adams
'Bundinn er bátlaus maðu'.