Greetings from Palmia Observatory
Well the early morning skies have been cloudy and I am reluctant to set an alarm clock anyway in order to measure Mercury's retrograde motion, so let's just scan the internet for science type news.
As the world starts to open up more for travel, we watch our upcoming cruise to Iceland for the latest news and it seems we might have a volcano, which is active right now, welcoming us to Reykjavik, when our cruise goes in a couple of months.
|Active volcano on outskirts of Reykjavik, Iceland (Source: phys.org)|
In other world news, we are saddened to see ongoing rocket launches aiming at targets inside Israel. This photo from the morning TV news showed the red glare of incoming rockets. Now for us here in relative safety we welcome the chance to look up at the sky and see the "string of pearls" of Starlink satellites, but watching incoming missiles is way beyond what we can understand of the anxiety of those seeing them. When I saw this image, I couldn't help but recall the refrain from the Star Spangled Banner, "and the rocket's red glare, ... that the flag was still there", but reimagine it to, "seeing the rocket's red glare, I wondered if my house would still be there." Hopefully, all will be resolved with peace and justice!
|These string of lights are of rocket red glare and not Starlinks (Source: KTLA 5)|
In other SpaceX news from Boca Chica we see lots of ongoing activity and hope to plan our second trip back there soon. In the meantime, there is so much activity going on there as we can see in this photo showing the traffic jam on Highway 4 as the Starship nosecone stress test fixture is transported back to the production site following completion of the stress tests.
|Traffic jam in Boca Chica as Starship prototype moves back to production yard (Source: @Spadre)|
In addition, there is another traffic jam of some sort on South Padre Island as photographers stack out their viewing positions. We hope to be there soon or maybe even better in a high rise hotel room, sipping a margarita, while waiting for the next test launch.
|Traffic jam at South Padre Island beach looking toward SpaceX launch site (Source: @Spadre)|
Speaking of the next launch, it seems that SpaceX is electing to go ahead and try using Starship SN15 again, just after its successful landing last week. Here you can see in this photo from BocaChicaGal, Mary, that SN15 has been lifted back onto the launch stand. This will be the first time a Starship attempts a 2nd launch and will go a long way on demonstrating the safety and reusability of the Starship.
|Starship SN15 back on launch pad for next test launch (Source: @BocaChicaGal)|
Ok, we just have to wait and try to get a sense as to when the next test launch will be and then see if we can still find flights down to Boca Chica. In the meantime, let's return to our previous topic of trying to understand the nature of cryptocurrency and Bitcoin with the help of the MIT Open Course Ware -- Block Chain and Money. There are new editions of the course, and there are a lot of technical details that we can't cover here, but let's just comment on a couple of items. If you want an easy, but technical introduction to Bitcoin, look up the paper by the infamous Bitcoin originator, Satoshi Nakamoto, " Bitcoin: A Peer-to-Peer Electronic Cash System."
Cryptocurrency, like Bitcoin, rely on modern mathematical and software concepts like cryptography of public and private keys, hash coding and consensus on a majority of online users to generate immutable blockchains of transactions. These functions make it possible to reduce the risk associated with transactions and thus each purchaser or trader can rest assured that the transaction will occur. It also does not need or rely on any central authority like a bank or government to achieve these goals.
|The history of cryptographic technology (Source: MIT Open Course Ware)|
The blockchain technology used in cryptocurrency relies on the public/private code keys, but for now let's bypass any discussion about that aspect and comment briefly about use of the hash function and consensus building among the participants.
I remember using some similar forms of hash functions when studying error correcting codes The hash function in cryptocurrency is used to generate signatures of the messages. Comparison of the hash values guarantees that the received message indeed came from the identified sender and that the message has not been modified by any other parties on the internet.
The hash function reduces a complex message to a standard sized group of characters. It is is easy to generate the hash function and virtually impossible to recreate the message from the hash, but you know that the message received has not been modified. The sender generates a hash function of the message and the receiver after decoding the message performs another hash function and the received hash better match the generated hash or the receiver knows the message has been altered.
|Hashing generates a signature of the original message (Source: MIT Open Course Ware)|
Consider the following example showing the hash value difference between two text messages. The two messages here are exactly the same except the 2nd one has a lower case letter instead of a capital case letter in the text "Palmia Observatory." The hash is 64 hexadecimal characters. You can see in this example how just a single change in the text message results in a different hash function with no recognizable connection to the change.
|Example showing how the hash changes with just a single error (Source: moveable-type.co.uk)|
Another key requirement of the blockchain technology is how consensus is reached so that a given set of messages and transactions are valid and should be added to the blockchain. Remember that one of the key benefits of cryptocurrency is that it reduces the risk of default among participants who do not know or maybe not trust each other to deliver on their promised transactions. Consensus building, and the agreement that the transaction is valid, is performed by participants called "bitcoin miners", who vie for the chance to generate consensus and add the transaction to the blockchain, by calculating the answer to a cryptographic puzzle. Solving this puzzle takes a lot of compute time and energy, but earns them the right to append to the block chain. The miners voluntarily do it because they get compensated with newly minted bitcoins
Refer back to the listed MIT Open Course Ware lectures for the details, but for now just keep in mind that this consensus building, which generates the trusted blockchain, consumes a lot of electrical power to keep the computers running. This power consumption is one of the recognized drawbacks to the Bitcoin process. Some bitcoin users don't accept this huge use of energy and are actively looking for and devising other techniques to achieve consensus without just burning up a lot of power. Many references list the amount of electrical power used, just to gain worldwide consensus, is the same as the total electrical power consumption of a country, like Austria. New techniques are being developed to generate consensus without consuming so much energy. One example of these improved techniques is call Etherium.
If you are interested in this consensus building technique and the operation of mining bitcoins, be sure to follow up with other lectures and readings listed on the MIT Open Course Ware site. In the meantime, so big users, such as Elon Musk, have backed away from Bitcoin and gone to other currencies that are more energy efficient.
|Growing interest in moving to "environmentally greener" cryptocurrencies (Source: @Telegraph Tech)|
Finally, since the clouds are in the way and we have spent way too much time on cryptocurrency, we end with a fun Facebook post from David N. about a smartwatch with a much needed keyboard. Hmm, at least I like the sort of steam-punk style of the thing!
|Finally, a smart watch with a keyboard (Source: D. Naiditch)|
Until next time, here from our burrow, stay safe, as we recover more of our freedom,