Neil Armstrong - A Rare Interview, 2011

The First Artificial Satellite

On October 4, 1957 life as everyone knew it was to forever change. The Homo sapiens has become the first species to ever space fare by deploying the first object to orbit the Earth. It was called Sputnik, I and it was the first artificial satellite of the Blue Planet. Sputnik I was followed by Sputnik II and the first living being ever to reach space, the dog Laika. Needless to say, an entire constellation of satellites followed afterwards, pervading Earth’s orbit with manned-made objects, and changing the life of the earthlings in a multitude of ways. This paper summarizes the launches and features of the first two Soviet satellites Sputnik I and II, as well as of the first successfully launched American satellite Explorer I, focusing on some of the systems aboard each satellite.

Sputnik I was the first Soviet satellite to launch into space and the first manned made object to orbit Earth. It was launched from Baikonur Cosmodrome on October 4, 1957 atop the Old Number Seven rocket.[1] Sputnik I orbited the Earth for 92 days, had about 184 pounds, and it was a contribution to the International Geophysical Year (1957-1958). Its main mission was to successfully launch into space and orbit Earth as the first artificial satellite ever built and deployed by humans. Sputnik I was an aluminum sphere with a diameter of 58 centimeters and equipped with four whip-like antennas about 2.4 to 2.9 meters long, deployed at 35 degrees angles. [2] The sphere was filled with nitrogen under pressure. The power source was made of three silver-zinc batteries housed inside a sealed capsule, while a ventilator was used for thermal regulation. [3] Sputnik I also had a one-watt transmitter that was received by amateur radios on Earth. Its beeping signal first hit the United States in the evening of October 4, 1957. [4] The orbital parameters of Sputnik I were: periapsis – 215 km, apoapsis – 939 km, period – 96 minutes, inclination – 65 degrees and eccentricity 0.05. [5]

Sputnik I was not equipped with an attitude stabilization system of any kind. Its communications system transmitter had one-watt of power and its signals were of 0.4 seconds alternatively at forty and twenty megahertz wavelengths. The power system consisted of three silver-zinc batteries. The satellite had four whip antennas of 2.4 and 2.9 meters length. [6] Sputnik I was indeed the embodiment of simplicity. It did not even have a payload other than its own body, the aluminum sphere and the beeping radio. Sputnik I did not receive any commands from ground stations, being only equipped with a transmitter and not a receiver. The thermal control system, powered by the three batteries onboard, consisted of a fan, a dual thermal switch and a control thermal switch. [7] The thermal control system successfully operated as planned.

Sputnik I operated for 1,400 orbits of the Earth, a mission of three months. The first artificial satellite was able to communicate with the ground for about three weeks, the actual duration of the batteries supplying the transmitter with power. The limiting factor in its ability to communicate was of course the short life of the batteries. The main mission of Sputnik I was massively met because it successfully reached the orbit of Earth and it stayed there for three month, simply demonstrating that humans are able to launch objects into space. The launch of Sputnik I in 1957 opened a whole new world of adventure for humanity. It was the beginning of what turned out being known as the space age.

Neil Armstrong: First Man on the Moon

The Sun and Earth's Climate

The effects of space weather on Earth's climate are currently still a controversy. The idea that solar activity affects climate on our planet is a given, considering that the sun is our source of energy and heat. We are all familiar with a cloudy and rainy day and its colder temperatures as opposed to a sunny, warm day. But does solar activity affect climate in the long run?

One idea was that sun spot activity could relate to changes in short term weather cycles and long term climate changes. In the beginning of the 20th century some scientists concluded that higher sun spot numbers contributed to a rainier and colder weather in some areas of the planet. Others claimed that more sun spots meant a brighter star and hence more heat on Earth. [1]

While short term effects on weather could be eventually verified, this was not the case with long term climate changes, so speculations on this matter went even further. Slight changes in solar radiations were blamed for ice ages on Earth, to the extent that such changes were mentioned in textbooks as possible causes for ice ages, shifts in ocean currents and volcanic dust. [2] These speculations were unconfirmed as soon as the space age started and spacecraft were able to measure ultraviolet radiation, which turned out to fluctuate during high peak solar activity, however which are not able to pass through the stratosphere and have an impact on the climate. Solar wind was also blamed for climate changes. It was suspected that high energy particles generated by solar wind could have an impact on the climate. [3]

In 1980 NASA tried to solve the mystery of the solar constant and its effect on climate by adding a special instrument to a satellite. This instrument detected small variations in the constant, depending on the number and position of sunspots. [4] Since the only assumed way solar activity could affect climate was in the amount of the sun’s output of energy, more and more scientists focused on this idea. During the Nineties, scientists focused on other similar stars and noticed their output of energy varies. As it later turned out, those stars were not so similar to ours after all. [5] With the beginning of the 21st century the increase in global temperatures over the previous century were yet again blamed on solar activity. With the help of numerous satellites, accurate sea surface temperatures were taken and a connection between temperature small variations and the 11 years solar cycle were noticed. [6]

I believe that so far very small influences of solar activity on the climate were revealed, and it does not seem that solar activity would be the main engine behind climate change on Earth. So far human activity has proven a much stronger engine that drives climate changes. Since there is not much we can do to influence solar activity, but there is a lot we can do in terms of our behavior and activities, we should definitely put more energy into that in regard to climate change. Solar activity has other strong effects on our planet and it is important to understand how these work and what we can do to prevent such issues.
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Notes:
[1]
American Institute of Physics. Changing Sun, Changing Climate?  February 2013. http://www.aip.org/history/climate/solar.htm (accessed April 26, 2013), para. 4-6.
[2] Ibid, para. 10-11.
[3] Ibid, para. 13.
[4] Ibid, para. 36.
[5] Ibid, 41.
[6] Ibid, 47.

Space Control

Space control is a method of watching and protecting space from any type of non peaceful space faring undergone by any nation of the world. From the beginning of the Space Race, it was soon realized that using space for anything but peaceful endeavors would have serious consequences on the future of the human race, and therefore international treaties were created and signed by the space faring nations of the time, stipulating that space can and must be used for peaceful purposes only and for the benefit of all mankind. Therefore, methods of space control must always be in place to assure such stipulations are continuously respected and maintained. During the Cold War era, one such method of space control were the reconnaissance satellites, [1] developed early in the Space Race mainly as response to the launch of Sputnik I and the suspicion that the Soviet Union already had such reconnaissance capabilities in place. Another implemented method was that of the anti-satellite systems, which of course implied the complete aggressive destruction of the enemy target. Such aggressive methods were however found to be quite repulsive after the end of the Cold War, and therefore new and less aggressive methods of space control had to be implemented.

Nowadays, a non-destructive space control tool implies temporarily and reversibly affecting the functionality of the enemy target without blowing it up. [2] This method does support the above mentioned definition of space control because it implies disabling the enemy hardware by make it dysfunctional and hence stopping any type of possible aggressive use of space. It also gives the participating nations a chance for discussing the issue on a diplomatic level rather than a military one. Answering aggression with aggression does not bear peaceful fruits, and therefore a space control tool that does not imply military action but still protects space is an excellent method. Another huge advantage of a non-destructive space control tool is the avoidance of generating more space debris. [3] Space debris has become a huge issue in orbit, and any more anti-satellite actions could only make the situation worse. Especially after China’s 2007 anti-satellite action, this issue has become an important one. This is yet another reason why answering an anti-satellite action with the same method would not be a smart way of space control. Besides this, such method would further contribute to the reduction of space debris simply by its capability to deactivate any anti-satellite weapon before detonation. In the same time, using a non-destructive space control method does not contravene international treaties that forbid the use of any type of weapons in space. An example of such non-destructive space control tools are the ones deployed to interfere and possibly jam the Libyan, Iranian and Chinese communication satellites. [4]