AST251 Project 3

Julian Yan 1006887415 April 3rd 2023 AST251 Project 3 P1 Q1. - This message is of intelligent origin, I am not 100% certain about how I have decoded it, but it is evident that the code is not random. It could resemble a humanoid figure; under it, it can be assumed to be an arrow. However, I don't know what the line could mean. The code will initially tell us that P1 has received our message. The content of the message could be them telling us what they look like and sending it to us. Q2. - With the information provided below, we can calculate the temperature and the density of the planet. - Spectral Type G - Stellar Luminosity (Solar Units) = 0.471 - Stellar Mass (Solar Masses) = 0.828 - Distance to Star (lightyears) = 177.6 - Planet Mass (Earth masses) = 1.4 - Atmospheric Pressure (atm) = 2.2 - Using Kepler's third law, we can calculate the semi-major axis of the exoplanet, determining the distance of the planet from the star. - T 2 = 4 π 2 G M s a 3 - 4 π 2 G = 1 ,T 2 = a 3 , 0.828 Solar Masses = 1.6468 ∗ 10 30 ( kg ) - 1.4 Earth Masses = 8.361 ∗ 10 24 ¿ ) - 515 2 = 1 1.6468 ∗ 10 30 a 3 ,a = 138,674,348,942 , P1’s Semi Major Axis is 9,026,240,885,876 (meters) - Radial Velocity curve is sitting at 0.135 m/s - Calculating the planet’s eccentricity - e = √ ( 1 − G M p aM s v radial ) - e = √ ( 1 − ( 6.6674 ∗ 10 − 11 m 3 k g − 1 s − 2 )( 8.361 ∗ 10 24 ) ( 9,026,240,885,876 )( 1.6468 ∗ 10 30 )( 0.135 ) ) ≈ 1

Julian Yan 1006887415 April 3rd 2023 AST251 Project 3 - N 2 = 13.8% - CO 2 = 26.9% - O 2 = 26% - H 2 O = 33% - N 2 O = 0.334% - With an atmospheric 2.2 times the amount of earth’s, the albedo of P1 could be estimated to be around 0.5. The atmosphere's composition containing oxygen, water, carbon dioxide and other essential gasses, appears to be similar to earth, making potentially intelligent life sustainable. - Temperature of P1’s host star, we will use this equation - L = 4 π R 2 σ T star 4 L star M star 2 - L star = 5600 K - Now we can calculate the temperature of the planet - T eq = ¿ - a: is the albedo of the star; σ : is the Stefan-Boltzmann constant; D: is the distance between P1 and its host star. - By plugging in all these variables, we can derive the equilibrium temperature of 283.6K (around 10.5 degrees Celsius), a little warmer than Earth’s, around 255K. However, this is only the equilibrium temperature of the planet to calculate the surface temperature of the planet. We must consider the atmospheric composition since the atmosphere has more CO2 and H2O. We could assume that the surface temperature could be between 30.5 degrees to 5 degrees Celsius. Q3. - This planet is habitable for intelligent life. However, because there is 51 % oxygen in the atmosphere, if the life on the planet does not grow as big as possible, it will experience oxygen poisoning, similar to when dinosaurs existed on Earth. During the time dinosaurs existed, the same animals today were much larger than before due to the extreme abundance of oxygen, which took up 30% of the atmosphere. Therefore, I believe that this planet can habit life, and the signals we receive are from humanoid creatures who are way larger than us. These creatures will also be able to withstand heat better than humans since the planet’s temperatures will be way higher than Earth’s. - On the other hand, their biochemistry will be similar to ours since there is CO2 in the atmosphere, and carbon is one of the most abundant elements in the universe and is crucial for creating life.

Julian Yan 1006887415 April 3rd 2023 AST251 Project 3 - e = √ ( 1 − G M p aM s v radial ) - e = √ ( 1 − ( 6.6674 ∗ 10 − 11 m 3 k g − 1 s − 2 )( 4.181 ∗ 10 24 ) ( 3,728,632,421,115 )( 7.6971 ∗ 10 29 )( 0.14 ) ) ≈ 1 - H 2 S = 36.3% - N 2 = 38.9% - C O 2 = 10.5% - SO = 9.2% - SO 2 = 2.53% - HF = 0.0507% - CO = 1.72% - S 2 O = 0.000625% - S 2 O 2 = 1.36 ∗ 10 − 5 % - With an atmospheric 9.6 times the amount of earth’s, the albedo of P1 could be estimated to be around 1. The composition of the atmosphere mostly contains oxygen and sulphur. - Temperature of P1’s host star, we will use this equation - L = 4 π R 2 σ T star 4 L star M star 2 - L star = 2966 K - Now we can calculate the temperature of the planet - T eq = ¿ - a: is the albedo of the star; σ : is the Stefan-Boltzmann constant; D: is the distance between P1 and its host star. - By plugging in all these variables, we can derive the equilibrium temperature of 70K (around -203.15 degrees Celsius), which is extremely cold. Even if the atmosphere can cause a greenhouse effect and warm the planet up a little, the planet’s temperature will still be deemed uninhabitable for intelligent lifeforms. Furthermore, the atmosphere contains ample sulphur, causing acid rain, which could be lethal to all lifeforms. Q3. - It is evident that the message sent from the planet is not random. There are many assumptions we can make as to how the civilization lightyears away survived on this extremely cold planet. - One assumption could be that their biochemistry is completely different. They have adapted to the freezing environment and have figured out ways to use acid rain for survival. Granting them free movement on the planet's surface.

Julian Yan 1006887415 April 3rd 2023 AST251 Project 3 - Another assumption could be that the star in their solar system was originally much hotter, but it has reached its limit and is dying, so they have evacuated their host planet in search for another suitable planet. On top of that, they have also depleted their planet’s resources and caused enough pollution to the atmosphere that the planet is now uninhabitable. - This gives us an understanding of this civilization that is way older than us, and their technology could be far more advanced than ours. For all we know, they could be a type 2 civilization that uses Dyson spheres and has colonies on all the planets in their solar systems. Works Cited Atmospheric pressure. Education. (n.d.). Retrieved April 6, 2023, from https://education.nationalgeographic.org/resource/atmospheric-pressure/