What are the justifications for space activities?

“Exploration is inherent to humankind… and it makes us human”. [1] Wanting to explore and understand the world is one of the main characteristics of Homo sapiens as species. Space exploration is a process expanding the human knowledge and the mankind’s range of action. [2] This is the ‘Space Age’, and space exploration is at least as important now as sailing in search of new discoveries was for the great explorers of the 15th – 16th centuries

In the past half a century, space exploration had a significant scientific, strategic, military and economic contribution. Space exploration allows many new discoveries. Never before has mankind achieved as much in scientific research. Such exploration is of crucial importance in this technological era. Why space exploration? In President Obama’s words,

…because broadening our capabilities in space will continue to serve our society in ways that we can scarcely imagine. Because exploration will once more inspire wonder in a new generation - sparking passions and launching careers. And because, ultimately, if we fail to press forward in the pursuit of discovery, we are ceding our future and we are ceding that essential element of the American character. [3]

The space race generated by the Cold War brought a significant improvement in people’s life. Space flight required highly developed computers and miniaturization. Humanity owes the existence of many gadgets, contributing to life improvement, to space exploration. For example, the development of sophisticated personal computers allowed the evolvement of distance learning: An online education in Space Studies was made possible by the existence of such advanced technology. It is also fair to say the progress made in medical technology has the same sources. Space exploration is also a wonderful opportunity for international cooperation in various missions. Since the end of the Cold War in 1991, such joint missions brought significant scientific discoveries. To give only an example, Cassini-Huygens, a joined mission between the American, European and Italian space agencies NASA, ESA, and ASI, has provided the scientific community with important information on planet Saturn and its moons.

Both robotic and manned exploration means are of significant importance in space exploration. Robotic missions are crucial in exploring places humans cannot reach yet. Astrophysicist Neil DeGrasse Tyson underlined this importance by referring to one of the most useful non-human tools scientists have for space exploration:

“The greatest explorer today is not even human. It’s the Hubble Space Telescope, which for nearly two decades has offered us all a mind-expanding window to the cosmos”. [4]

Human space flight has both and immediate and long-term importance. Direct exploration offers closer insights, familiarizing the human species with life in space, and it is likely to provide further survival on other celestial bodies when planet Earth will be no longer suited for human habitation.

To summarize, there seem to be a few good reasons to add to the inherent human trait of curiosity and need to discover new territories, as to why space should be explored:

• understanding and discovering the unknown
• unravel the secrets of the universe and understand our place in it
• further survival of the human species when Earth will no longer be habitable
• defense on a national, but also global basis
• advances in technology
• international cooperation by sharing a common goal.

Finally, in the process of space exploration, humans have re-discovered Earth. One of the most remarkable experience by a crew in space was that of Apollo 8 watching the Earth rising. In the documentary “In the Shadow of the Moon”, Jim Lovell shared this amazing experience as follows:

…We learned a lot about the Moon, but what we really learned was about the Earth. The fact that just from the distance of the Moon, you can put your thumb up, and you can hide the Earth behind your thumb. Everything that you have ever known, your loved ones, your business, the problems of the Earth itself, all behind your thumb. And how insignificant we really all are. But then how fortunate we are to have this body, and to be able to enjoy living here amongst the beauty of the Earth itself. [5]

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Notes:

[1] Dordain, Jean-Jacques. “Space exploration in the 21st Century: Global opportunities and challenges”. http://www.nasa.gov/offices/oce/appel/ask/issues/38/38i_space.html (accessed September 19, 2011), 2.

[2] Ibid, 2.

[3] Martin, Rachel, Travers, Karen. “On the Defensive, President Obama Pledges Commitment to NASA, Space Exploration”. ABC News, 15 Apr. 2010. http://abcnews.go.com/WN/president-obama-touts-billion-budget-boost-nasa-potential/story?id=10387427 (accessed September 19, 2011), para. 4.

[4] Tyson, Neil deGrasse. “Why America Needs to Explore Space”. Parade Magazine. August 5, 2007. http://www.haydenplanetarium.org/tyson/read/2007/08/05/why-america-needs-to-explore-space (accessed September 19, 2011), para. 10.

[5] Sington David. In the Shadow of the Moon. Discovery Films, 2007.

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 References

Dordain, Jean-Jacques. “Space exploration in the 21st Century: Global opportunities and challenges”. NASA Project Management Challenge 9 Feb 2010. http://www.nasa.gov/offices/oce/appel/ask/issues/38/38i_space.html (accessed September 19, 2011)

Martin, Rachel, Travers, Karen. “On the Defensive, President Obama Pledges Commitment to NASA, Space Exploration”. ABC News, 15 Apr. 2010. http://abcnews.go.com/WN/president-obama-touts-billion-budget-boost-nasa-potential/story?id=10387427(accessed September 19, 2011)

Sington David. In the Shadow of the Moon. Discovery Films, 2007.

Tyson, Neil deGrasse. “Why America Needs to Explore Space”. Parade Magazine. August 5, 2007. http://www.haydenplanetarium.org/tyson/read/2007/08/05/why-america-needs-to-explore-space (accessed September 19, 2011).

Falcon 9

The Falcon 9 is a low cost launch vehicle designed by SpaceX, powered by liquid oxygen (LOX) and rocket grade kerosene (RP-1).[1] This vehicle has been chosen by NASA to take over re-supplying the International Space Station after the retirement of the Space Shuttle in July. Falcon 9 has just completed a wet dress rehearsal at Cape Canaveral, Florida, in August, and it is scheduled to launch on November 30^th to deliver the first payload to the International Space Station.[2] 

First launched on June 4^th 2010, Falcon 9 successfully placed the Dragon capsule in orbit, opening the way for a whole new generation of private rockets as cargo suppliers and eventually astronauts carriers to the international research laboratory in Earth’s orbit, and further into deep space. While NASA had already built its rockets with private companies, Falcon 9 is even more private, and much more cost-effective: the 1.6 billion contract between NASA and SpaceX covers a minimum of 12 flights to the ISS.[3] The launch vehicles developed by SpaceX seem to have increased reliability and performance, and reduced cost by a factor of ten.[4] Falcon 9 is estimated to cost between 54 and 59.5 million dollars per flight.

The Falcon 9 is equipped with nine Merlin engines designed by SpaceX and believed to be very reliable, with the capability of sustaining an engine failure during the flight, and still completing the mission successfully. The vehicle also has a hold-before-release system that holds it down until confirmed that all of the vehicle’s systems function properly, with an automatic shutdown and propellant unloading if any problem is detected.[5] Each of the nine engines has a 125,000 lbf sea level thrust, giving the rocket a total thrust at liftoff of just over 1.1 million lbf. Falcon 9 has a length of 180 ft, and a width of 12 ft.[6]

The November 30^th launch carrying the Dragon capsule to the International Space Station is the first under the partnership between NASA and the commercial space industry for using private rockets to deliver payload to the ISS, and an important milestone in developing the role of the private sector in space flight.[7] Dragon has autonomous rendezvous and docking systems, and it is re-usable through its water landing parachute design. A successful Falcon 9 will be followed by Falcon Heavy, believed to be the world’s most powerful rocket, able to lift nearly twice the payload of the Space Shuttle. Falcon Heavy will be the first rocket with propellant cross-feed from the side boosters, to the center core, allowing the center core to carry most of its propellant after the side boosters jettison, a performance similar to a three-stage rocket.[8]

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[1] SpaceX, Falcon 9 Overview, 2011. http://www.spacex.com/falcon9.php#falcon9_overview (accessed September 5, 2011).

[2] Clark, Stephen, SpaceX fuels Falcon 9 rocket; Dragon to arrive next month, Spaceflight Now, August 16, 2011. http://spaceflightnow.com/falcon9/003/110816wdr/ (accessed September 5, 2011).

[3] SpaceX, Falcon 9 Overview, 2011. http://www.spacex.com/falcon9.php#falcon9_overview (accessed September 5, 2011).

[4] ORBCOMM, I. c., ORBCOMM and SpaceX Set Plans to Launch Satellites on Next Falcon 9 Launch. Business Wire. EBSCOhost. (accessed September 5, 2011).

[5] SpaceX, Falcon 9 Overview, 2011. http://www.spacex.com/falcon9.php#falcon9_overview (accessed September 5, 2011).

[6] SpaceX, Falcon 9 Launch Vehicle Payload User’s Guide. http://www.spacex.com/Falcon9UsersGuide_2009.pdf (accessed September 5, 2011), p. 8.

[7] Clark, Stephen, SpaceX fuels Falcon 9 rocket; Dragon to arrive next month, Spaceflight Now, August 16, 2011. http://spaceflightnow.com/falcon9/003/110816wdr/ (accessed September 5, 2011).

[8] SpaceX, Falcon Heavy Overview, 2011. http://www.spacex.com/falcon_heavy.php (accessed September 5, 2011).

Pluto – Planet of Dwarf Planet?

For many years, the scientific field of astronomy has acknowledged that the solar system is made of a star and many bodies in orbit around it. While such celestial bodies were found by the million, only nine of them stood up by exhibiting peculiar properties. These nine objects were called planets. Because some of them are easily visible with the naked eye, they were known to humanity since ancient times. Others waited to be discovered. The smallest and the last of the nine, Pluto was discovered in 1930 and proudly took its place as the ninth planet of the solar system. Pluto was considered a planet for 75 years, until a new discovery came along.

In 2005, a cosmic object five percent bigger than Pluto was discovered. This new celestial body was named Eris. Scientists believed Eris was the tenth planet of our solar system. This discovery rekindled the idea of what exactly a planet is, and Pluto had to be re-evaluated. Classification is necessary in order to understand the place of an object in the universe. As scientists explore space, they discover more and more celestial objects every day, and in a field evolving at such a rapid pace, classification should be flexible. Planet classification changed over time. The ancient Greeks, observing the night sky, realized that some of the points of light move against the background of fixed stars. They called these lights ‘planet’, the ancient Greek word for ‘wanderer’. For thousands of years, the word planet, a term inexact scientifically, was sufficient to distinguish other celestial objects than stars. From this point of view, Earth was not a planet, as it was not wondering on the sky of the Ancient Greece. This view changed completely with the invention of the telescope. While at the time of its discovery in 1930 Pluto was considered a planet, with the recent discoveries in the Kuiper Belt it only made sense that a re-classification of the celestial objects in the solar system was in place. Therefore, the International Astronomical Union voted to downgrade Pluto from the rank of planet, to that of dwarf planet. This act stirred up a lot of controversy, as Pluto has been the ninth planet for 75 years. Many astronomers still do not accept the official classification of planets and dwarf planets given by the International Astronomical Union. Planet or dwarf planet, the debate over the demotion of Pluto is more a sociological matter than a scientific one. The topic of defining a planet is still being vigorously debated in the world of astronomy (NASA Headquarters).

According to the new classification, a planet has to have the following three characteristics: to orbit the sun, to have enough gravity to assume a nearly round shape, and to have cleared its neighborhood of other objects. Unlike planets, dwarf planets did not clear their neighborhoods, and they are also not classified as moons of other planets (NASA Headquarters). Pluto orbits in the Kuiper Belt, and therefore its neighborhood is very busy with other objects. When it comes to controversy, it is quite easy to debate the issue of clearing a celestial object’s neighborhood. Many astronomers assert Jupiter has not completely cleared its orbital path of Trojan asteroids, and therefore it cannot be considered a planet. However, with Jupiter being the largest object in the solar system after the sun, it would be hard to disqualify it to the level of dwarf planet, not to mention that Jupiter has actually cleared its neighborhood, and still clears other planet’s neighborhoods, by swallowing most of the asteroids or comets on their path to other planets, an important detail for the earthlings’ hope for a peaceful life. Since not clearing its orbital path is not a property of a planet, the criterion is actually fulfilled. Other astronomers debate that, if any of the planets would orbit the sun inside the Kuiper Belt, it would not classify as a planet, as it would not be able to clear such a busy neighborhood. They claim that the new planet classification focuses more on what is around a planet, rather than its properties. This idea is also debatable, because Mars and Jupiter are separated by the asteroid belt, and they still cleared their neighborhood long time ago.

Pluto has other peculiar characteristics making it quite different than all the planets in the solar system. Its orbit is tilted 17° out of the plane of the solar system, it moves in an eccentric ellipse, and its orbit crosses the orbit of another planet. Unlike the planets, Pluto is neither rocky, nor gaseous, but made mainly of three types of ice: carbon monoxide, methane and nitrogen. Its moon Charon has a rotation tidally locked by Pluto, and while our planet has done the same thing to its moon, Charon is pretty large as compared to Pluto, and still it has tidally locked Pluto’s rotation (deGrasse 3).

Pluto is therefore a very peculiar celestial body, and its only common characteristics with the planets are that Pluto also orbits the sun, although in an eccentric ellipsoidal orbit, and its shape is round and similar to the planets. While some people might say that not clearing its neighborhood of space debris and having a few unique traits should not mean Pluto does not deserve to be called a planet, it does not matter so much what Pluto is, but rather that it is a member of the solar system, and has its own contributions.

In the meantime, scientists should stay flexible in regard to classification. Classification can and should change based on new knowledge. Humanity is barely making its first baby steps in space exploration, and therefore the amount of surprise waiting out there is so huge, that human classification based on limited knowledge may not mean so much. As far as Pluto is concerned, NASA’s New Horizons mission, a space probe traveling from Earth to the end of the solar system, with an estimate time of arrival in 2015, will provide new insights about the dwarf planet and its surroundings, and who knows how the classification of the celestial objects in the solar system will look like at that time?

References

Nasa Solar System. What is a Planet? A video electronically retrieved from http://www.youtube.com/watch?v=zKRBrlnOUOM 

deGrasse, T. N. (1999).Pluto is not a planet. Natural History Magazine, February 1999. Electronically retrieved from http://www.planetary.org/explore/topics/topten/tyson_pluto_is_not.html

Earth Rising

We learned a lot about the Moon, but what we really learned was about the Earth. The fact that just from the distance of the Moon, you can put your thumb up, and you can hide the Earth behind your thumb. Everything that you have ever known, your loved ones, your business, the problems of the Earth itself, all behind your thumb. And how insignificant we really all are. But then how fortunate we are to have this body, and to be able to enjoy living here amongst the beauty of the Earth itself (Jim Lovell).