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timbo
2003-May-21, 07:02 PM
Who knows how many years an American president can be president for? Everyone - naturally.

There are some fairly broad assumptions that are included in the book - ones that are so natural (for Americans) that they are probably overlooked. For example, on page 29 - talking about the closest star being 4.2 light years and comparing that to a presidential term.

Also, the discussion on seasons on page 17. Seasons are just a silly way that humans have broken up the passage of time. Its a little like months - why are they 12 and not 13 (or 52). In Australia, spring starts on the 1st of Sept - each season starts on the first of a month. Summer - 1st Dec, Winter - 1st Jun, Autumn (fall for you americans) starts on the 1st of March. Its just the way that we have decided to break our year up.

If you are going to reprint the book, can you change the word "believe" in the sentence "these countries believe that the actual first day of spring is six weeks before the equinox" (mid page 17) to something else. It sort of implies that "how stupid can these people be - they actually believe that spring starts before the equinox ...".

Anyway - I'm really enjoying the book and didn't even realise that these bad astronomy misconceptions had to be debunked. I already knew most of them.

EXCEPT for the Coriolis effect and the bathroom - I'm still thinking about that one - but more on that later.

dgruss23
2003-May-25, 01:15 AM
timbo wrote: Also, the discussion on seasons on page 17. Seasons are just a silly way that humans have broken up the passage of time. Its a little like months - why are they 12 and not 13 (or 52). In Australia, spring starts on the 1st of Sept - each season starts on the first of a month. Summer - 1st Dec, Winter - 1st Jun, Autumn (fall for you americans) starts on the 1st of March. Its just the way that we have decided to break our year up.

Welcome to the board Timbo!

Thats an interesting point you raise Timbo. Its logical from the standpoint or the Earth's orbital motions to have the equinoxes and solstices be the starting dates for the seasons. But the start dates of seasons could be considered arbitrary in the sense that most people equate the seasons with the weather.

Do you know why the 1st of sept ect were designated as the seasonal start dates in Australia?

kilopi
2003-May-25, 02:50 AM
Its logical from the standpoint or the Earth's orbital motions to have the equinoxes and solstices be the starting dates for the seasons.
But there is some disagreement with that, even on this board (http://www.badastronomy.com/bad/misc/badseasons.html) :)

I forget what the BA says about the seasons in his book though. Guess I'll have to look it up.

The Bad Astronomer
2003-May-25, 04:20 AM
I urge people to remember that there is an entire website attached to this board (http://www.badastronomy.com/bad/misc/badseasons.html).

David Hall
2003-May-25, 12:28 PM
Another thing about when the seasons start, even if you fixed a date, it wouldn't stay that way. The precession of the poles means that 13,000 years from now, summer and winter will have changed positions.

I've also recently realized that for the same reason, at the dawn of civilization some 6000 years ago the seasons must have been slewed some 3 months from where they are today. I wonder if that's taken into account in historical studies?

dgruss23
2003-May-25, 12:45 PM
Its logical from the standpoint or the Earth's orbital motions to have the equinoxes and solstices be the starting dates for the seasons.
But there is some disagreement with that, even on this board (http://www.badastronomy.com/bad/misc/badseasons.html) :)

I forget what the BA says about the seasons in his book though. Guess I'll have to look it up.

I like the BA's idea. Its has always bothered me that we hit the first day of summer and then the days are getting shorter. Do you think we'd have more luck with this change than we had in our efforts to switch to the metric system? :roll:

kilopi
2003-May-25, 12:50 PM
Another thing about when the seasons start, even if you fixed a date, it wouldn't stay that way. The precession of the poles means that 13,000 years from now, summer and winter will have changed positions.
That's a common misconception (http://www.badastronomy.com/phpBB/viewtopic.php?p=8908&highlight=precession#8908). :)

The Earth's calendar is actually based upon that precession. It is fixed so that the seasons always will occur on about the same dates.

The Earth takes slightly more than 365.25 days to go around the Sun, whereas the year is based upon slightly less than 365.25 days.


I've also recently realized that for the same reason, at the dawn of civilization some 6000 years ago the seasons must have been slewed some 3 months from where they are today. I wonder if that's taken into account in historical studies?
The correction of Pope Gregory reset the start of the seasons to that which was common in ancient times. Before that, dates are fairly ambiguous anyway.

I like the BA's idea. Its has always bothered me that we hit the first day of summer and then the days are getting shorter.
You realize that the end of summer and the start of fall would then be in the first week of August, right? In most states of the USA, August is as hot as June, and maybe even hotter.

dgruss23
2003-May-25, 01:31 PM
kilopi wrote: dgruss23 wrote:
I like the BA's idea. Its has always bothered me that we hit the first day of summer and then the days are getting shorter.

kilopi wrote:

You realize that the end of summer and the start of fall would then be in the first week of August, right? In most states of the USA, August is as hot as June, and maybe even hotter.

But the BA's point was based upon defining the seasons independent of weather because weather patterns vary so much around the world. The weather we have in New York doesn't fit well with the seasons as it is. The first day of spring is March 21, but most years its not until the second or third week of May before we can count on the temperatures being above the 40's day and night - Its no way to live! :cry:

kilopi
2003-May-25, 02:13 PM
But the BA's point was based upon defining the seasons independent of weather because weather patterns vary so much around the world. The weather we have in New York doesn't fit well with the seasons as it is. The first day of spring is March 21, but most years its not until the second or third week of May before we can count on the temperatures being above the 40's day and night - Its no way to live! :cry:
Yahbut, under the plan, Spring would start six weeks earlier than that even! How would you like the first day of Spring to be in the first week of February?

So, in a sense, they already are defined independent of weather.

dgruss23
2003-May-25, 06:28 PM
Here are the seasons in my area during a typical year:

Nov1-Jan7 Winter

Jan 8-Feb15 Really, Really bad winter

Feb 15- March 15 winter

March 16-April 15 winter thinking about taking it easy

April 15- May7 winter begrudingly gives way to spring as long as spring promises to behave and not get above 45 degrees in full sunlight. Fortunately spring doesn't always listen to winter's menacing threats.

May 7 -June 7 Spring

June 8- Aug 8 Summer

Aug 9 - Sept 15 10:00 am - 5:00 pm summer
5:01 pm - 9:59 am Fall

Sept 16- Oct 15 Fall

Oct 15- Oct 31 Winter starts kicking fall in the backside to get fall out of the way.

:D

g99
2003-May-27, 05:48 PM
It also depends on where you are. Here in Florida we only have three real seasons: Summer, winter, and Spring. We have no real fall. The leaves stay onn all year and it does not slowly cool down. It will be 70 deg. one day and literally the next it will be in the higher 50's (thats winter for us....uggghhh i hate the heat). Yah sure it gets to the 20'as for a few days, but come on, thats a thaw everywhere else.

(all temps in deg. F)

kilopi
2003-May-27, 07:32 PM
Yah sure it gets to the 20'as for a few days, but come on, thats a thaw everywhere else.
(all temps in deg. F)
Are you sure that one isn't in deg. C? :)

BlueAnodizeAl
2003-May-30, 02:55 PM
Here are the seasons in my area during a typical year:

Nov1-Jan7 Winter

Jan 8-Feb15 Really, Really bad winter

Feb 15- March 15 winter

March 16-April 15 winter thinking about taking it easy

April 15- May7 winter begrudingly gives way to spring as long as spring promises to behave and not get above 45 degrees in full sunlight. Fortunately spring doesn't always listen to winter's menacing threats.

May 7 -June 7 Spring

June 8- Aug 8 Summer

Aug 9 - Sept 15 10:00 am - 5:00 pm summer
5:01 pm - 9:59 am Fall

Sept 16- Oct 15 Fall

Oct 15- Oct 31 Winter starts kicking fall in the backside to get fall out of the way.

:D


And the seasons during my typical year.

1 Random Week in January Mild Winter (One Freeze, 30F)

Everything Else Mild to Hot Summer (60F-100F)

I have no concept of this "season" thing. I'm perfectly content with the current definition, cause either way it makes no difference to me.

g99
2003-May-30, 07:05 PM
heh! BlueAnodizeAl: I am not that far from you. I'm in Gainesville, FL.
Where in Orlando are you?

------------------------

Right now it is 84 deg. in Gainesbville. the high for todzy is 90 deg. and it is not even the middle of summer yet. And don't even talk about humidity. I walk outside and i am drenched.

dgruss23
2003-May-30, 11:07 PM
BlueAnodizeAl wrote: And the seasons during my typical year.

1 Random Week in January Mild Winter (One Freeze, 30F)

Everything Else Mild to Hot Summer (60F-100F)

I have no concept of this "season" thing. I'm perfectly content with the current definition, cause either way it makes no difference to me.


Gee, it must be a pain to have to put on the snow tires for only 1 week! :D

g99
2003-May-31, 03:33 AM
BlueAnodizeAl wrote: And the seasons during my typical year.

1 Random Week in January Mild Winter (One Freeze, 30F)

Everything Else Mild to Hot Summer (60F-100F)

I have no concept of this "season" thing. I'm perfectly content with the current definition, cause either way it makes no difference to me.


Gee, it must be a pain to have to put on the snow tires for only 1 week! :D

Snow tires? hah! you mean snowflake (singular) tires. :-)

dgruss23
2003-May-31, 12:52 PM
BlueAnodizeAl wrote: And the seasons during my typical year.

1 Random Week in January Mild Winter (One Freeze, 30F)

Everything Else Mild to Hot Summer (60F-100F)

I have no concept of this "season" thing. I'm perfectly content with the current definition, cause either way it makes no difference to me.


Gee, it must be a pain to have to put on the snow tires for only 1 week! :D

Snow tires? hah! you mean snowflake (singular) tires. :-)

Yeah, and up here we have a special sunbeam (singular) sunblock. :cry:

BCstargazerr
2003-Jun-04, 07:24 PM
good day all :)

i couldn't help noticing a couple of things

I always thought that the closest star to Earth was our humble sol at 8 light-minutes from us compared to 4 and some light-years for Proxima Centuri. but perhaps it's just me and my mental status :o

my second point is about the different "local" seasons. On the lower north shore of the st Lawrence river near newfoundland they describe their seasons in that particular way:

July 15th 11am-2:45 pm=Summer
rest of the year: Winter :P

dgruss23
2003-Jun-05, 12:36 AM
BCstargazer wrote: July 15th 11am-2:45 pm=Summer
rest of the year: Winter

Thanks for reminding me that the grass is not always greener - sometimes its whiter. :o

Hale_Bopp
2003-Jun-09, 05:41 PM
Remember, meteorologists do define seasons differently. Meteorological summer is the hottest three months of the year. Meteorological winter is the coldest three months of the year. Spring and fall are the three month transition periods.

I have seen local meteorologists on television explain the difference between meteorlogical and astronomical seasons and actually do a pretty good job of it.

Rob

Geo3gh
2003-Jun-12, 12:55 AM
Here in Tucson, we have five seasons: Spring, Dry Summer, Monsoon Summer, Fall and Winter.

Of course, that's meteorological seasons rather than astronomical seasons.