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Rishik Dhar
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Mind boggling facts. Amazing how our perception is so limited in its capability. 
How fast is Spaceship Earth traveling through space? : The answer is not as simple as one would assume. Because all motion is relative. So it could be a variety of different answers. Depending on the frame of reference, the answer could be zero or a variety of different answers. We do know that everything is moving. The Earth, the Sun, the Milky way, the local galactic cluster..... all of it. Read on to look at the motion from different perspectives....

Article Extract: The problem with motion is that “true motion” doesn’t exist.  The best we can do is talk about “relative motion” and that requires something else to reference against.  What you consider to be stationary (what you chose to define your movement with respect to) is a matter of personal choice.  The universe isn’t bothered one way or the other.

Relative to the Earth: The Earth turns on its axis (you may have heard), and that amounts to about 1,000 mph at the equator.  The farther you are from the equator the slower you’re moving.  This motion can’t be “ignored using relativity”, since relativity only applies to constant motion in a straight line, and movement in a circle is exactly not that.On a planetary scale it’s responsible for shaping global air currents.

Relative to the Sun: The Earth orbits the Sun at slightly different speeds during the year; fastest around new years and slowest in early July (because it’s farther from or closer to the Sun respectively).  But on average it’s around 66,500 mph.  By the way, the fact that this lines up with our calendar year (which could be argued to be based on the tilt of the Earth, which dictates the length of the day) to within days is a genuine, complete coincidence.  This changes slowly over time, and in several thousand years from now it will no longer be the case.

Relative to the Milky Way: The Sun moves through the galaxy at somewhere around 52,000 mph.  This is surprisingly tricky to determine.  There’s a lot of noise in the the speed of neighboring stars (It’s not unusual to see stars with a relative speed of 200,000 mph) and those are the stars we can see the clearest.  Ideally we would measure our speed relative to the average speed of the stars in the galactic core (like we measure the speed at the equator with respect to the center of the Earth), however that movement is “sideways” and in astronomy it’s much much easier to measure “toward/away” speed using the Doppler effect.  Of the relative speeds mentioned in this post, the speed of our solar system around the galaxy is the only one that isn’t known very accurately.

Relative to the CMB: The Milky Way itself, along with the rest of our local group of galaxies, is whipping along at 550 km/s (1.2 million mph) with respect to the Cosmic Microwave Background.

Article Link and source:

Spaceship Earth concept:

Spaceship earth from Discovery:

From Urban Astronomer :

Rotational motion (NASA) :

Earlier post on spaceship earth:

Our solar system's tail :

Does the sun rotate? :

Pics courtesy: Main pic on left - Pic right top - from NASA via Pic right center: The solar system is not a vortex (artist's impression) - from Right bottom - from Chandra

#space #science #earth #spaceship #speed #relativemotion  
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Brand Ambassador Me!

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One of my favorite contemporary Bollywood music albums. All songs are phenomenal compositions.

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Straight from the expert...

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A very concise explanation of OSGi framework and its goals in solving problems of tight coupling and dependency management by means of service oriented architecture within a JVM. A must read for beginners.!files/pdf/Kriens-WhyOSGI.pdf

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It was so cool to meet a role model, here I am with Rod Johnson at GraphConnect after party on Nov 6th, San Francisco. #Graphconnect   #neo4j  

Wonderful two days of learning Neo4j and exploring the idea of Graph DB right from the Core API, to overall NoSQL landscape, deployment, data modelling and open challenges.

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My Bullet!
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