Posted on 03/29/2018 12:57:17 PM PDT by BenLurkin
Newton’s laws tell us that satellites orbit the Earth in perfectly circular or elliptical orbits, repeating their path again and again (assuming that gravity is the only force acting on them). However, this is not true at low altitudes, say below 1,000km, because the satellite is then moving through the Earth’s atmosphere. This causes “aerodynamic drag” (air resistance) – a force that opposes the satellite’s velocity, which effectively turns the orbit into a downward spiral towards the Earth’s surface.
In theory, we can calculate drag perfectly to predict the path of a satellite. This can be done using an equation that depends on the velocity of the satellite (v²), the density of the atmosphere (ρ), a numerical coefficient that depends on the shape of the satellite and its orientation with respect to the airflow (C), and the object’s area (A). For those who are interested, the equation is: D = ½ × C × ρ × A × v². But you don’t have to understand the equation to grasp why it is so hard to calculate drag.
The spacecraft’s velocity is easy to measure fairly accurately using observations. However, the other parameters are highly uncertain – making it difficult to determine Tiangong-1’s path. For vehicles such as cars and aircraft, C can be estimated theoretically or with computational fluid dynamics and measured experimentally in a wind tunnel. The main problem here is that Tiangong-1’s shape is complex, and the object is uncontrolled and tumbling chaotically, resulting in a constantly changing C.
The other unknown is the density of the atmosphere, which decreases with altitude. However, particularly at high altitudes, this varies due to a number of unpredictable factors – the most important of which is solar activity.
(Excerpt) Read more at space.com ...
Now it's 118.46 miles up and doing 17424.97 MPH
Why is this so hard if NASA can predict the weather 100 years out? (sarc)
It's very nice.
Yeah, but it was a good episode anyway!
That’s not nearly as complex an equation, but it depends greatly on money. Her probability of stopping is inversely and exponentially related to the money she can raise.
HPPCII = 1/($cf + $bt + $gc + $sc)**3
Where
HPPCII is Hillary’s Probability of Putting a Cork In It
$cf is dollars from the Clinton Foundation
$bt is dollars from the book tour (almost zero)
$gc is dollars from graft and corruption
$gs is dollars from evil people like George Soros
(**3 is ‘cubed’)
It will burn lots higher up than 50 mi. Once it gets below 100 miles up, you’re looking at reentry within minutes.
Are you trolling? Since I actually saw part of skylab at the Miss Universe pageant in 1979? And of course, everytime the ISS flies overhead, I watch it if it’s not cloudy outide. And I’ve seen plenty of non-photoshopped pics...and I used to go to church with Rick Husband.
OOPS! Wrong subscript on the last variable... Should be:
HPPCII = 1/($cf + $bt + $gc + $gs)**3
Where
HPPCII is Hillary’s Probability of Putting a Cork In It
$cf is dollars from the Clinton Foundation
$bt is dollars from the book tour (almost zero)
$gc is dollars from graft and corruption
$gs is dollars from evil people like George Soros
(**3 is ‘cubed’)
Beat me to it
Thats the Tide Pod mother ship
You use to go to church with Rick’s Husband? kinky
Anyone can see a moving satellite with their own eyes if they choose to. Just spend enough time looking at the sky after dark or before dawn. I’ve seen dozens.
I told him we’ve already got one.
~snicker~
Hook that sucker up to a go-kart.
He’s trolling. Lonely loser club member. Will talk to anyone just to keep from killing himself.
There you go....using logic again!
What was strange was "Heavens Above" satellite tracking did not have anything going over at that time.
I hope it lands on my old boat even though it’s
parked next to my house.
I like it. Now it all depends upon whether Russian collusion is commutative, associative , or distributive!
Flat earther too?
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