THE EARTH MOVESYes yes you all know that right? But DO YOU KNOW IT?
And so do all the other planets, stars etc
Let us assume for a minute that your job is SPACE NAVUGATOR and you have to be able to find your way home...
Let us look first at just the Earth
The Secrets of the Universe
What is the Speed of the Earth?This page deals with the actual speed of the Earth moving through space. There are many directions of travel and various speeds that have to be taken into consideration. We will divide this into categories and will provide two explanations. One in lay terms so the average person may easily understand the complex movements our planet and the other in scentific details.
Why is this of importance?
Why is this of importance? For any discussion on the posibility or the probabiliy of space flight dealing with interstellar flight, it is necessary to have this data.
Imagine for a moment that you have a faster than light or warp capable star ship...
Considering the speed at which the Earth moves, even a short mission away from Earth would result in the planet being
millions of miles away from the point of origin at the time you left. Nasa calculations to reach a simple point like the Moon require enormous calculations and pin point accuracy. Any small error left uncompensated would result in Astronauts missing the Earth on return.
Motion, Speed and Direction of Travel of Earth Through Space
Or
"How the Hell Do I Calculate the Way Home"
A study by R. Schmidt July 21, 2006
Disclaimer:The following figures are approximate values for demonstartion only! Please DO NOT use them to calculate actual flight paths. We are not responsible for people getting "Lost in Space".
Consider yourself sitting at your computer on a chair...How fast are you moving?
1. The Earth "wobbles" on its polar axis. This motion is not relevant (IMO) to the calculations needed to return to earth from interstellar space as it is an "in situ" motion, but it exists.
2. The Earth revolves {spins} on its axis. For these calculations we will use the equator with a circumference of approx. 25,000 miles. One rotation of Earth is approx. 24 hours. Again this is "in situ" motion so not relevant to space travel, but adds to our "stationary chair" model
25000/24 =1041.7 MPH
3. The Earth is orbiting the Sun once a year. The circumference of the Earth's orbit is approx. 607.6 million miles {or 940 million kilometers}. One year is approx. 365 days
365 days X 24 = 8760 hours
607,600,000/8760 = 69,360.73 MPH
So far we have basically 3 Directions of Motion {Wobble, Spin and Orbit} and a combined speed of 1041.70 + 69,360.73 = 70,402.43 MPH for a person sitting in a chair at the Equator.
{Note: We will do the actual vector calculations at the end}
The following source gives more detail and a more precise calculation based on your latitude and more exact figures. Anyone dizzy yet? A little motion sickness perhaps?
NASA - What is the speed of the Earth?When you take into account the three-dimensional picture of the Sun's movement through our Milky Way Galaxy, things get very complicated.
4. The sun {and hence the solar system} is moving towards the constellation Hercules, namely to the star Lambda Herculis at 12 miles per second {or 20 kilometers per second} which is 43,200 MPH
5. The Solar system is also moving upwards, at 90 degrees to the plane of the Milky Way, at 4.34 miles per second or 15,624 MPH. But we are actually leaving the Galaxy, out about 50 light years now and will be moving out to 250 light years before it reverses. Details of the mechanics of this are explained in the link below. We also crossed the Galactic plane 2 million years ago.
6. The Solar system is orbiting around the Galaxy at an "estimated" speed of 124 miles per second {or 200 kilometers per second} which is 446,400 MPH. The way that figure has been calculated can be found at the link below.
Stanford University - What is the speed of the Solar System? This is where finding our way home becomes difficult, as we do NOT have an actual true figure for this calculation. The further out we go, taking into account the various motions and speed, the more difficult it becomes to get precise calculations ergo the more room for error. Until we can actually go and measure the distances, a "best guess" is all we have. Over the past few decades these values have been revised several times, and are constantly being added to today.
From an Astronomer's point of view this is not a problem, as they are merely observing from Earth and can fix their calculations when they get new data… no harm done… just reprint the maps.
BUT from a spaceship pilot point of view…touring just within our own galaxy… the problems are enormous.
From a navigator's point of view, we can leave out the "wobble" and the Earth's rotation as those movements are "in place". For later calculations we could also leave out the Earth orbiting the Sun, because if we can make it back to the Sun, I am sure we can locate Earth.
So our "armchair Astronaut" is now moving through 6 different directions and a combined speed of approximately 574,585 MPH
69,361 MPH Spin and Orbit
43,200 MPH Towards Lambda Herculis
15,624 MPH Perpendicular to Galactic Plane
446,400 MPH Orbiting the Galactic Center {or Galactic Spin Rate}
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574,585 MPH Speed of Earth within Our Galaxy
So for every hour you are away from the solar system, your planet is moving half a million miles, and in several directions…
Now if you want to leave the galaxy add another 1,339,200 MPH to the calculations. This is the speed the galaxy is moving through the universe. But THEN you really get into difficulties pin pointing you reference point. Details can be found here…
So you see… the propulsion unit is the least of your worries….
You better have a REALLY GOOD NAVIGATOR.
NASA - What is the Speed of our Galaxy?