Discussion 1 – Astronomy
In this discussion activity, you will have the opportunity to reflect upon what you have learned during this module and how that has influenced your views on the existence of extraterrestrial life, intelligent or otherwise.
Thoroughly answer the following questions:
- Based on what you have learned in this module, what would you say are the most important ingredients or conditions required for the emergence of life? Support your answer.
- Are you more or less likely now, after what you have learned in this module, to believe that there is extraterrestrial life “out there somewhere?” Intelligent life? What is it that you learned that leads you to have that view?
- Do you think we should try to contact alien civilizations? Do you think an intelligent alien civilization would want to communicate with us? Why or why not?
To earn full credit, you must also reply to the initial posts of at least 2 classmates. In your replies to classmates:
- Compare and Contrast his/her answer on what is necessary for life to arise with yours.
- Agree or disagree with a classmate’s argument for or against the likelihood of the existence of extraterrestrial life in our galaxy. Support your argument.
- Agree or disagree with a classmate’s view on whether or not we should try to communicate with aliens and whether an intelligent alien civilization would want to communicate with us. Support your argument.
Initial post:
Vincent’s post:
This discussion will examine the key ingredients or conditions required for the emergence of life. I will also research if I believe that there is extraterrestrial life somewhere in the universe. Finally, I will discuss my viewpoint on should we try to contact alien civilizations. After the universe that we know of today was formed over 14 billion years ago the creation of life has been a captivating subject. Where did life begin in the universe is Earth the only planet in the universe that sustains living organisms. There is limited knowledge on this subject because scientist does not have evidence outside of Earth that shows life on distant planets in the universe. I will start with understanding the requirement from life on Earth before making any assumptions about life in distant worlds.
Life according to the textbook requires elements such as carbon, oxygen, and nitrogen combined with other elements in space to produce compounds needed to form life on Earth (OpenStax, 2016, p. 1114). “In particular, life on Earth is based on the presence of a key unit known as an organic molecule, a molecule that contains carbon” (OpenStax, 2016, p. 1114). Hydrogen and carbon when combined creates hydrocarbons, which are key chemical compounds that serve as a basis for biochemistry (OpenStax, 2016, p. 1114). According to Astrobiology Primer v2.0, there are five major stages of the origin of life (Domagal-Goldman et al, 2016). “First, the simplest organic building blocks were synthesized, starting from the inorganic substrates”, which contacted amino acids, carboxylic acids, nucleobases, and carbohydrates (Domagal-Goldman et al, 2016). “Second, small organic molecules started self-organizing, giving rise to larger, more complex organic molecules” that contained small proteins, peptidomimetics and nucleotides (Domagal-Goldman et al, 2016). “Third, complex molecules started interacting with each other, giving rise to the first reaction pathways” in protein, peptide-RNA, and RNA worlds (Domagal-Goldman et al, 2016). “Fourth, macrostructures arose from the spontaneous aggregation of the simpler molecules, which led to compartmentalization” of membrane, metabolism, and replicator (Domagal-Goldman et al, 2016). “Fifth, the system was capable of being shifted from chemical equilibrium, maintaining homeostasis and undergoing evolution” creating protein-RNA-DNA life (Domagal-Goldman et al, 2016).
After reading this module, I believe there is extraterrestrial life inside our universe. If we take in consideration the evidence that we have collected for Mars we can assume that during the early life of the planet conditions were set to sustain living organisms. Some of the evidence that were collected show that Mars once had liquid water, which is one primary ingredient, needed for life that we know of on Earth (OpenStax, 2016, p. 1126). Although the NASA Viking landers never found any evidence of organic molecules, which is needed to make life, does not mean billions of years ago life did not exist on Mars. This is an example of how life could exist on other planets besides Earth. When we look at the five stages of life that I laid out earlier in the discussion, I believe that there are intelligent life forms somewhere out there.
I honestly believe that we should not try to contact alien civilizations until we gather enough data that can prove they are peaceful alien civilizations. The most difficult problem that we would face is how we communicate with intelligent life forms were we could engage in a common dialog. I believe that if we did not have a common dialog we could cause harm to both sides, which could result in hostility. I think that they are trying to communicate with us now but because there is some much that we do not know about other galaxies and planets, we cannot notice their messages. Maybe they have advance technology that we have not developed yet to receive and transmit message back to them.
Your response:
Carlos response:
In my opinion, there several ingredients that are essential for the development and further evolution of life. Most importantly, the location of the host planet, will be the biggest factor in the sustainment of life. It will need to be a rocky planet similar to ours, with an atmosphere, orbiting a G-type star like our sun at the perfect distance to replicate the living conditions we found on earth. In addition, I think it will even need to have a tilt similar to the one Earth has, not to mention the most essential requirement; water. Furthermore, this planet will need to be under the perfect conditions in order to be a host to life. At least life as we know it, there could be total different set of organism perfectly adapted to harsher environments out there. The biggest thing that leads me to believe that there is life out there, is the vastness of the Universe. There are billions upon billions of stars in the cosmos, stars so distant that we can’t even see. Seems a little naïve to think that earth is the only living planet in a Universe full of galaxies, and stars. Somewhere out there, out of our technological reach there has to be a planet with life millions of years ahead of us or behind us. On a different note, I don’t necessarily believe that we should reach out to other possible civilizations. Perhaps, they could be more advanced, and who knows what kind of intentions they could have with our vulnerable species. Maybe, decades down the road when our technology evolves to a point where we can master interstellar travel, and evolve as a civilization, maybe then we can reach out other worlds.
Your response: