Mars Previewer 2 question

I am trying to make sense of what I saw and have imaged using Mars Previewer
2.

Which timezone are we here in the UK -1, 1 or 0 (thinking about BST and GMT
etc.)?

cheers

-halli-

In message , -halli-
writes
I am trying to make sense of what I saw and have imaged using Mars Previewer
2.

Which timezone are we here in the UK -1, 1 or 0 (thinking about BST and GMT
etc.)?

cheers

-halli-


-1
0100 BST = midnight UT or GMT
--
Dave Smith
website: http://www.graviton.demon.co.uk
Castle Point Astronomy Club: http://www.cpac.org.uk/

"Dave Smith" wrote in message
...
In message , -halli-
writes
I am trying to make sense of what I saw and have imaged using Mars
Previewer
2.

Which timezone are we here in the UK -1, 1 or 0 (thinking about BST and
GMT
etc.)?

cheers

-halli-


-1
0100 BST = midnight UT or GMT

Thank you, Dave.

-halli-

JRS: In article , seen in
news:uk.sci.astronomy, -halli- posted at Wed,
27 Aug 2003 23:56:12 :-
I am trying to make sense of what I saw and have imaged using Mars Previewer
2.

Which timezone are we here in the UK -1, 1 or 0 (thinking about BST and GMT
etc.)?

GMT midnight is at 1 a.m. BST. BBC World Service @ 648m proves this
nightly.

--
© John Stockton, Surrey, UK. Turnpike v4.00 MIME. ©
Web URL:http://www.merlyn.demon.co.uk/ - w. FAQish topics, links, acronyms
PAS EXE etc : URL:http://www.merlyn.demon.co.uk/programs/ - see 00index.htm
Dates - miscdate.htm moredate.htm js-dates.htm pas-time.htm critdate.htm etc.

Wasn't it -halli- who wrote:
I am trying to make sense of what I saw and have imaged using Mars Previewer
2.

Which timezone are we here in the UK -1, 1 or 0 (thinking about BST and GMT
etc.)?

Whenever I want to know what time zone someone is in, I look at their
message headers. Yours says "Date: Wed, 27 Aug 2003 23:56:12 +0100" so
you're in the +1 hour time zone.

--
Mike Williams
Gentleman of Leisure

"Mike Williams" wrote in message
...
Wasn't it -halli- who wrote:
I am trying to make sense of what I saw and have imaged using Mars
Previewer
2.

Which timezone are we here in the UK -1, 1 or 0 (thinking about BST and
GMT
etc.)?

Whenever I want to know what time zone someone is in, I look at their
message headers. Yours says "Date: Wed, 27 Aug 2003 23:56:12 +0100" so
you're in the +1 hour time zone.


Hmm, I am confused now. Does this mean you agree with Dave Smith that the
setting should be -1, or are you and Dr Stockton saying the setting should
be +1?

My brain hurts! I have not needed to think for the past 5 and a half weeks,
and now I am returning to school (teacher not pupil) I have too much to
think about. We need more holidays! ;-)

Thanks for all of your help

-halli-

In message , -halli-
writes

"Mike Williams" wrote in message
...
Wasn't it -halli- who wrote:
I am trying to make sense of what I saw and have imaged using Mars
Previewer
2.

Which timezone are we here in the UK -1, 1 or 0 (thinking about BST and
GMT
etc.)?

Whenever I want to know what time zone someone is in, I look at their
message headers. Yours says "Date: Wed, 27 Aug 2003 23:56:12 +0100" so
you're in the +1 hour time zone.


Hmm, I am confused now. Does this mean you agree with Dave Smith that the
setting should be -1, or are you and Dr Stockton saying the setting should
be +1?

My brain hurts! I have not needed to think for the past 5 and a half weeks,
and now I am returning to school (teacher not pupil) I have too much to
think about. We need more holidays! ;-)

Thanks for all of your help

-halli-


Here is the relevant section from the help file.
Quote
Time

Enter the local time of observation in hh:mm format. Mars Previewer does
not consider Daylight Savings Time, so add or subtract an hour as
needed.

Timezone

Enter here your Time Zone, in hours west of Greenwich. if your location
is east of Greenwich your time zone will be negative.

Mars previewer II - (c) 1997-1999 Leandro Rios
end quote

BST is like being 1 hour to the East so if the time is entered in BST
then the time zone needs to be -1 to get the correct view of Mars.
Clearly the program intends you to convert the time to GMT or UT first
and then there is no ambiguity.

I used the program on the night of Wed 27/Thurs 28. At 0100 BST and a
time zone setting of -1 in Mars Previewer II and had agreement between
my image and the simulation. (See my website - Planets page)

It is also straightforward to check by comparing the predictions e.g.
Time = 00:00 and Timezone = 0 with Time = 01:00 and Timezone = -1
With Timezone set on +1 a different view is obtained.

I hope this helps.
--
Dave Smith
website: http://www.graviton.demon.co.uk
Castle Point Astronomy Club: http://www.cpac.org.uk/

JRS: In article , seen in
news:uk.sci.astronomy, Mike Williams posted at
Thu, 28 Aug 2003 20:31:00 :-
Wasn't it -halli- who wrote:
I am trying to make sense of what I saw and have imaged using Mars Previewer
2.

Which timezone are we here in the UK -1, 1 or 0 (thinking about BST and GMT
etc.)?

Whenever I want to know what time zone someone is in, I look at their
message headers. Yours says "Date: Wed, 27 Aug 2003 23:56:12 +0100" so
you're in the +1 hour time zone.

Where the offset is given as a signed number, it is dangerous to assume
any particular sign convention without additional data. There is, for
example, an apparent tendency for Americans to use Abs of the
difference, and then to decide of a sign convention that leaves the
number, for use in the USA, positive. But sometimes they don't do that.

That's why I prefer to state one particular instant in both systems;
there can be no doubt that that means, and it is up to the reader to
determine how to use it. Midnight GMT occurs at 1 a.m. UK Summer Time ,
and that should be easy enough to understand - and anyone who can listen
to real-time BBC World Service, or who can use www.heavens-above.com,
has access to GMT/UTC.

Using Newsgroup headers presumes a correctly-configured system; granted,
they commonly are. Except that some use services, such as Google,
outside their time zone.

Members of this group can determine the proper time from the Moons of
Jupiter.

--
© John Stockton, Surrey, UK. Turnpike v4.00 MIME. ©
Web URL:http://www.merlyn.demon.co.uk/ - FAQqish topics, acronyms & links;
some Astro stuff via astro.htm, gravity0.htm; quotes.htm; pascal.htm; &c, &c.
No Encoding. Quotes before replies. Snip well. Write clearly. Don't Mail News.