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Deep space network

I was discussing with a friend of mine about why early pictures of moon, say from the apollo missions, were so blurry. Well, astronomers don't enjoy the kind of speeds you and I do every day on our mobile phones, laptops and desktops. Most of us get impatient about low internet speeds, curse our service if the internet connection changes from 3G/H/H+to 2G. On the other hand, the data transmission rate from space craft back to earth is in the range of 100s of kbps. Deep space network, the title of this post, is a collection of radio antenna distributed all over the earth which are used to communicate with space craft and DSN NOW is a site which shows which antenna is communicating with which satellite, what the transmission rate is, what frequency they are transmitting at and so on. There are a lot more satellites than there are antenna so i guess data is pulled from the satellites based on demand or maybe periodically. As of now, MAVEN, the NASA mars mission is operating at a data rate of ~500 kbps.  On the other hand, MOM, the ISRO mars mission is operating at a 999 bites per second. You can check it yourself. Before i comment on the large different in data rates, I shall check a couple more times to see if this is a temporary rate of transmission. Coming back to the point, I hope you can understand now why the images from the Apollo are grainy. In fact, in efforts to increase this data transmission rate from space, NASA scientists have developed OPALS, an instrument on the ISS which can communicate with a base station on earth using lasers and were successful in communicating with the ISS for over 2 minutes while reaching a maximum data transmission rate of 50 mbps! With those speeds, astronauts can finally buffer youtube videos and watch netflix movies with ease!

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