Spacecraft Event Time
Spacecraft Event Time (SCET) is the spacecraft-local time for events that happen at the spacecraft. SCET is used for command programs that control the timing of spacecraft operations and to identify when specific events occur on the spacecraft relative to Earth time.
SCET versus Earth time
Since signals between the spacecraft and Earth are limited to the speed of light, there is a delay between the time an event happens on the spacecraft (such as the transmission of data taken from an instrument reading) and the time that a signal reporting the event reaches Earth. Similarly, there is a delay between when instructions are sent from Earth and when the spacecraft receives the instructions. The length of delay is relative to the distance between the sending and receiving points. Failure to take this delay into account could result in inaccurate data or mistakes in spacecraft control.
Calculating SCET
Determining the Spacecraft Event Time involves taking the time at Earth and adding or subtracting the signal travel time, depending on whether the signal is being sent to or received from the spacecraft. For events transmitted from the spacecraft to Earth, the SCET of an event on the spacecraft can be defined as equal to the ERT (Earth-Received Time) minus the OWLT (One-Way Light Time). For events transmitted from Earth to the spacecraft, the calculation is TRM (transmission time) plus OWLT. For example, if a signal were received on Earth at exactly 11:00 UT from a spacecraft showing that it had just completed a maneuvering thrust, but the spacecraft was four light-hours away from Earth (the distance of the New Horizons spacecraft at one point as it approaches Pluto), the SCET time of the thrust maneuver would have been four hours earlier, at 07:00.
Podcasts:
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by TQ
Grind
by: TQWe on a grind y'all, uh-huh, uh-huh, yeah
What, we on a grind y'all, uh-huh, uh-huh, yeah
I often dream of better days
And different time (different time)
And I just don’t know a better way
For me to get mine
That’s why I got to shine
The game been good to me
Ain’t nothing gonna stop my grind (nothing gon stop it, no no)
So it ain’t no need to fake on me (ain’t no need)
There are some folks just too far behind in their mind
And it’s a crime crime
But little Terry gonna keep on rolling
I see you trying to get me
Never gonna let them busters get to me
Cos I’m a get there, even if you with me
Always keep my tired eyes open
Like EJ you can’t stick me
I got something for the whole damn world to see
So I’m gonna give it up
You best believe me
Ain’t gonna get me off of my grind
It’s exactly what it seems to be
For all of those times (you know those times)
When you wish for some prosperity
All you could find (all you could find)
Was hate to see them lies
So you tell somebody else
To get it off your mind (wanna get it off your mind)
Well I start hearing melodies (sweetest things, sweetest things)
So I grab my pen and pad and recline
On my grind
And that’s how Terry gonna keep on rolling
I see you trying to get me
Never gonna let them busters get to me
Cos I’m a get there, even if you with me
Always keep my tired eyes open
Like EJ you can’t stick me
I got something for the whole damn world to see
So I’m gonna give it up
You best believe me
Ain’t gonna get me off of my grind
We on the grind y'all
Cuz we some worldwide riders
What, we on a grind y'all, uh-huh, uh-huh, yeah
You jackin' me up, you takin' my cash
All my life, LBC, for my city I mash
All these OG's and BG's and wannabes and L-O-C's
The only friends I got is my 2-1-3
That’s my dog Snoop-T-Woop and my nigga N-A-T-E
Can't forget about my nigga H to the dizzy
Pressure and strifes, them wanna take my whites
But these jaw jacks and hood cracks
Will make you break some bizacks
What you thought?
Ya know what I'm sayin', we on the grind like that
Thought we was trippin'?
Ha ha, all you thought we had was jeans and t-shirts?
What? We hustlin' cuz we want it all, Brand new socks and drawers, fool
I see you trying to get me (can’t get me, no)
Never gonna let them busters get to me
Cos I’m a get there, even if you with me
Always keep my tired eyes open
Like EJ you can’t stick me (can’t stick me)
I got something for the whole damn world to see
So I’m gonna give it up
You best believe me