comet ques

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angeline
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comet ques

Post by angeline »

yoz~

Wanna ask does anyone know is there any webby or other ways to find out where is the comets' location and time??? Will be down to Redang island next wk, hopefully can catch the comet. Oh yah, i dun have any equipment... haha~ so will try to spot it using naked eyes lor. That y need to know which constellation and time comet will at.. hee :lol: At least i wun be spoting the wrong stuff too :wink:

Thankz
*Angeline*
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fizzy123
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Post by fizzy123 »

Hi angeline,
u can try Heavens-Above, they give u the exact position of the comet at any instant of time. Presently comet NEAT is in cancer and moving towards Gemini. It is bright with 1.6 mag should be easily spotted under dark sky. Gd luck finding and seeing. Clear skies.
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kingkong
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Post by kingkong »

try the star chart at:

http://skyandtelescope.com/observing/sk ... ation=true

i looked at Neat again this evening.
because cancer is not a bright const, it may not be easy for newbie (like me) to find. had to star hop a bit before i found it.
i think the comet and cancer is not easily visible to unaided eyes in light poluted urban areas (including my yards). i found it first in a 8x42 bino.
comet Neat is fading. but since it was my first trip to cncer, i took a look at the beehive cluster (in cancer) hmmmm.... nice!
good hunting. :wink:
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Airconvent
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Post by Airconvent »

Can also download the PDF maps here :

http://www.skymaps.com/downloads.html

They're updated monthly. For Singapore, locate Polaris and draw an imaginary line through it. This is the horizon and it rotates as the night progresses...

rich
The Boldly Go Where No Meade Has Gone Before
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angeline
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Post by angeline »

thankz man! but i need the infos for malaysia. tired skyandtelescope, but when i choose the city.. it said that there is no such city found in malaysia??? :cry:
I cant spot in Spore esp outside my window... too many street lamps le.. kekeke :P Unless its not near the horizon lor.

Real thankz again :)
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kingkong
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Post by kingkong »

angeline wrote:thankz man! but i need the infos for malaysia. tired skyandtelescope, but when i choose the city.. it said that there is no such city found in malaysia??? :cry:
which city are you in? can pm me if you prefer to keep that private.
i can even find my small ulu town in the list! :lol:
at least, i may help you to find the lat & long.
i find the s&t interactive map very user friendly.
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ykchia
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Post by ykchia »

Hi Angeline and folks:

I have been using skymapPro for many years. The demo version is good enough to locate the comet using binoculars

http://www.skymap.com/products.htm

then go to

http://cfa-www.harvard.edu/iau/Ephemeri ... t01Cmt.txt

for positional files to locate ALL comets..

Skymap pro produces good printed map too.

As far as location is concern, enter the long and lat. Use heavens-above to find your nearest town. we are +8 hrs UT..

Actually if you know your star fields - who cares for the long and lat ( for Goto folks).. the relative positions of the comet(s) vs the background star is what you are after.

Look for the 'fuzzy' patch ....

Good luck

rgds
ykchia
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fizzy123
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Post by fizzy123 »

Aaaarrgghhh...... I need some desparate help from atro n especially ETX gurus. I tried to key in the info of comet NEAT from NASA emphemeris into the ETX. The outcome is like tis when I select NEAT from ETX :

ETX:
R.A. : 8h43m m d= degree
DEC: 27d 29'

while Heavens Above gives,

R.A. : 8h 44m30.7s
DEC: 24d29'31"

1)The autostar is 1min lesser in R.A. while 3d more in DEC compare to actual sky situation, why?

2)If I use a 25mm modified achromat 50d FOV ep, producing 14x magnification, wat are my chances to spot it?

3) The problem is also there when I key in info for comet LINEAR also 1min lesser 3d more, why?

I could not seek for the comet manually as I do not hav a finder scope. The comet is going dimmer day by day n the worst thing iz dat I am stuck in camp saturday night only time to observe. It is always cloudy then. Haaaaiiiiizzzzzz. :cry: :? :( :cry: :( :( :(
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weixing
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Post by weixing »

Hi,
I'm not an AutoStar user, so I'm not sure what is the problem you face. Anyway, you do not require a finder scope, your scope is already a finder scope. Using the eyepiece you mention, you have a Field of View of 3.5 degree and you should be able to spot it quite easily. I can spot the comet using my 8x50 finder under the stadium full light pollution.

By the way, you can always join my observation session on the grass field near Tampines Stadium on friday, saturday or sunday night (depend on weather).

Have a nice day.
Yang Weixing
:mrgreen: "The universe is composed mainly of hydrogen and ignorance." :mrgreen:
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Airconvent
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Post by Airconvent »

Hi,
Here is an exerpt from the ETX forums on several ways to add a comet to an autostar. I personally prefer to import Meade's file direct into the autostar and save the trouble of wondering what to key in. I tried it once and Neat has been dead centre...



Adding Comets

Subject: AutoStar Update Vers 2.4
Sent: Thursday, July 12, 2001 21:59:13
From: monopertuz@yahoo.com (Fernando Pertuz)
Well, using the Drag & Drop approach I finally managed to get correct
comet LINEAR A2 data into the AutoStar. Keep in mind that this rather
cumbersome method only bypasses the problem (a bug in Meade's AutoStar
Update program version 2.4) and doesn't fix it.

In a nutshell this is what I did.

In the "AutoStar Update" page of Meade's website there is a link at the
bottom of the page that retrives comet data. I got the file and saved
it as MYCOMETS.TXT. This file is already in the .CMT format required
but saving it as .TXT makes it easier to use Window's NOTEPAD to edit
it. It contains umpteen comets, some of them not even HUBBLE can see!

Using NOTEPAD, I erased all but the comets I wanted to put in the
AutoStar (almost ALL of them) and saved the reduced file as MYCOMETS.CMT

In the EPHEMERIDES sub-folder within the MEADE folder (bottom level) I
deleted a file named LIBCOMET.ROM

After connecting the ETX & AutoStar to the PC I started Explorer,
resized it to about an eight of the screen size, displyed the folder
that contained MYCOMETS.CMT and moved Explorer's window off to the left
leaving only the displayed list of files.

Without closing Explorer, I started the AutoStar Update Program and
moved its window to the right of the screen such that I could see
Explorer's window.

Now using the mouse I click over the file MYCOMETS.CMT and WITHOUT
RELEASING THE MOUSE BUTTON, I move the mouse (drag) over the "COMET"
button in the Updater's window and release the button (drop). (This
procedure creates a new LIBCOMETS.ROM file.)

Clicking the COMET button confirmed not only that the comets were there
but all were tagged to be sent to the AutoStar handbox. DO NOT click on
an individual comet as the Updater may change the epoch date and render
that data useless.

I then proceeded to download the efemerides data to the handbox.

Testing the result was another story, the overcast is NOT on my side so
I started the scope, faked an allignment, connected it to the PC,
started up SkyMap and using the handbox I slewed to Linear A2 and was
glad to see that it pointed to the exact same location calculated by
SkyMap.

By the looks of it, my sighting of Linear A2 is destined to be a comet
icon on a SkyMap display or pictures of the darned thing.

Fernando Pertuz

And:

Subject: A2.4 versus Comet Epochs...
Sent: Thursday, July 12, 2001 22:13:51
From: rseymour@wolfenet.com (richard seymour)
Personally, i key in individual comets via the Autostar keypad.
But drag-and-drop -does- seem to work.

One MAJOR difference in v22eR compared to previous is *much*
improved Comet tracking. If you played with 22eH, you'd find that
it occasionally predicted -retrograde- motion over the course of
a day (at least with Linear A2). With 22eR A2 appears within my
ETX90's 26mm eyepiece 8 times out of ten, and the other two times
it's within one "spiral search" cycle...

You might just try only doing a [send firmware to Autostar]
when you update (but do a [get ephemerides from autostar] first!

Sometimes the User Data survives the update.

The Training, etc, has to be replaced because their assigned locations
-change- from version to version... there's no good reason for it,
but they do.
Feel free to send notes to engineer@meade.com requesting that those
values ("in the EEprom") survive from version to version.

have fun
--dick

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

Subject: How to Enter A Comet to the Autostar... the complete example
Sent: Wednesday, April 24, 2002 21:05:46
From: rseymour@wolfenet.com (Richard Seymour)
How to add a Comet to the Autostar (without using the Updater)
(see http://www.weasner.com/etx/autostar/gui ... aries.html <guide-libraries.html>
for how to do it -with- the Updater)

Select > Object > Solar System > [enter][scroll up] Comets [enter]
You're now seeing:
Comets
Select

Now press [scroll down] and you're seeing:
Comets
Add

Press [enter]
it asks for a Name.

Use the scroll up/down keys to cycle thru letters and numbers,
the big <- and -> slew keys to move from space to space,
and press [enter] when you're happy.

It will now ask for Epoch date:
23.5-Mar-2002 [enter]

Perihelion Distance: (how close it gets to the sun, in AU (earth orbit radii)
1.63562
Eccentricity: (how round the orbit is)
1.0000
Arg. of Per.: (argument of Perihelion, the RA of closest sun approach)
20.4450
Lon Asc Node: (RA where it heads above the equator)
269.011
Inclination: (tilt of orbit compared to equator)
110.478
Absolute Magnitude (how bright it would be at a fixed distance)
10.5

That's it... the Autostar can now predict where the comet will be.
Since these are -early- numbers, expect them to change over the
next few weeks... so don't plan to use this set in late May 2002.

If you scroll -up- from Comets/Select, you'll reach Comets/EDIT
which lets you easily tweak the data already stored for a Comet.
Try playing with it (just keep pressing [enter]) with a Comet
already in your Autostar.

have fun
--dick

For reference, here's the line from Meade's Comets reference link:
C/2002 H2 (LINEAR) |2000|20020323.461 | 1.63562 |1.00000 | 20.445 |269.011
|110.478 |10.5 |10.0 | MPEC 2002-H40

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