ATT_LAN ver.2
					
				August 9, 1995
				T. Nakagawa

1. Att_Lan ver.2
================

The following points are revised.
	- Using the time of time-corrected IRTS_LAN files
	- one file / day corresponding to concatenated IRTS_LAN
	- Using new orbit data	
	- Orbit estimates errors are included
	- Control errors are included
	- Many bugs of the old version are fixed
We expect that ver.2 files are more accurate than previous files. The
errors are now being estimated.

Please note that the ver.2 files dose not use any information of the
STS data.


2. File Name
============

An ATT_LAN file is named after its corresponding IRTS_LAN file.
For example, if the name of an IRTS_LAN file is the following
	irts_04170049cc.lan,
then the name of the corresponding ATT_LAN file is the following
	att_irts_04170049cc.2.lan.

		
3. Format
=========

The format is slightly changed from the old version.

3.1. Primary header (one line, 120 bytes):

	Format  Item          	 comments

	A8	file category	"ATT_LAN " to designate ATT_LAN file
	A24	HK file 	the name of the concatenated HK file
				from which this ATT_LAN file was created
	A24	IRTS_LAN file	indicates the corresponding IRTS_LAN file
	A18     time(start) 	start time
	A18     time(end)	end time
	I10    	# of frames   
	I3	version No.     2 
	A14	orbit file	the name of the orbit file on which
				this ATT_LAN file is based on.
	A1	LF	

This file dose not have the secondary header.

3.2 data

One frame consists of 1.024 sec of data. One frame per one line. The
format of each 	frame is the following (120 bytes / line):

	Format  Item		comments

	A18	Time 		time
	F9.4	R.A. 		R.A.(1950) of IRTS center axis (deg)
	F9.4	Dec.		Dec.(1950) of IRTS center axis (deg)
	F9.4	Roll Angle 	Roll Angle of IRTS FPI (deg)
	F9.4	SAA		Solar Avoidance Angle (deg)
	F9.4	EAA		Earth Avoidance Angle (deg)
	F9.4	LAA		Lunar Avoidance Angle (deg)
	F9.4	x_sat		Satellite x_Position (km)
	F9.4	y_sat		Satellite y_Position (km)
	F9.3	z_sat		Satellite z_Position (km)
	I2	Thrust		Thruster Flag 
	I1	BIO/MEX		BIO/MEX On/Off Flag
	I1	BA		Brazil Anormally In/Out Flag
	I1	GP		Galactic Plane In/Out Flag
	I1	DN		Day/Night Flag
	I3	Ver		Version of Attitude data (2)
	A11	dummy 
	A1	LF

Comments
	time format		MM/DD hh:mm:ss.sss (18 bytes, no null)
	On/Off Flag ->	 	1:On, 0:Off
	In/Out Flag ->	 	1:In, 0:Out
	Thruster Flag ->	1: thruster was turned on within 32s
				2: thruster off
	Ver. No. -> 		2