Introduction
In this report, my mystery solar system is composed of nine planets. From these, five form the inner solar system while four from the outer solar system. From the planets forming the inner solar system, I chose planets one and five to research and report on. On the other hand, for the outer solar system, I chose planets two and four to research and reported on.
Mystery solar system
The table below shows some important data about the aforementioned planets.
I believe planets 1 and 5 of the inner solar system fall within the terrestrial planets category since they are close to the sun (0.21 and 1.24 AU, respectively). Moreover, this is attested by the fact that they have no moons. If that is not enough, analysis of their sizes reveals that they are either smaller or almost equal to that of the planet earth (radius of 0.68 and 1.07 earth masses for planets 1 and 5, respectively). In order to arrive at the probable composition of these planets, their densities are what drove me to my conclusion. These planets are denser (5.5 and 4.53 g/cm3 for planets 1 and 5, respectively) vis-Ã -vis the other two outer solar planets. To this end, I concluded that they are made up of both rocky substances and heavy metals. Of note, the gases that are most likely to be dominant in these planets that are closer to the sun are the heavy gasses. As such, I concluded that these planets are encapsulated by carbon dioxide and nitrogen gases. Finally, with the composition of these two planets in mind, I concluded that they are heated internally courtesy of radioactivity (due to unstable heavy metals), accretion, and differentiation (when materials drop from a higher point).
On the other hand, I believe that planets 2 and 4 of the outer solar systems fall under jovian planets since they are gigantic (10.66 and 8.78 earth radii). Moreover, this is underscored by the fact that they are far away from the sun (9.84 and 53.21 AU from the sun). Data revealing their densities confirm that these planets are composed of lighter materials. The densities of planets 2 and 4 are 1.12 and 0.68 g/cm3, respectively. These are less than those of the other two planets forming the inner solar system. As such, I concluded that they have composed of both lighter gasses (He and H) and ices (H2O). The other evidence that confirms my conclusion is that these planets have relatively higher spin (15.2 and 8 hrs respectively) as compared to those of the inner solar system (8057.21 and 40.87 hrs, respectively). This makes them have relatively flattened poles. Having the composition of the planets in mind, I concluded that the internal heat of the planets emanates, chiefly, from the friction between gasses.
Planet 1 and 5 (Terrestrial planet)
When one is on the surface of planet one, he/she will weigh less since the gravitational pull is less than that on the earth. Basically, the force of gravity is proportional to the planetary mass. Since its mass is 0.305 earth masses, the gravitational pull is expected to reduce by this factor.
Assuming person 1 weighs x N on earth;
This person will weigh 0.305*x N Ξ 0.305x N.
Conversely, while on planet five, this person will weigh slightly heavier due to the fact that this person will experience a greater gravitational pull that is proportional to the planet’s mass (1.013 earth masses). Therefore, this person will weigh 1.013*x N Ξ 1.013x N.
The interior of terrestrial planets are likely to be hot enough to power geological activities now or in the past owing to the internal processes that continue to happen in situ. The energy derived through the processes of accretion, differentiation, and radioactivity are the ones responsible for the geological activities witnessed in these worlds. Radioactive decay is particularly an important process that initially generated a lot of interior heat on these worlds when they were still young. This process is significant in heat generation since these worlds are dominated by radioactive isotopes. Vitally, the heat generated through this process (E=mc2) is proportional to the planetary mass and the percentage composition of the heavy metals. As such, a lot of heat is anticipated from this process. Basically, a combination of these processes generates a lot of interior heat vital in driving geological activities.
The surface processes that are likely to happen on the surfaces of these worlds include impact cratering, volcanicity, tectonics, and erosions. Impact cratering happens when impactors, particularly comets, bombard the surfaces of terrestrial planets at terrific velocities (30,000 – 250,000 Km/hr), thereby creating craters on their surfaces. On the other hand, volcanicity happens when magma rises to shoot outside through a vent owing to an inbuilt pressure within the mantle. Plate tectonics happens when the plates forming the crust collide, shear, or separate. The forces behind these motions originate from the hot mantle that is always under convectional current. Finally, erosion happens when the rocky materials are shifted thanks to the agents of erosion.
The surface temperature of a planet is given by the formula below:
T= b/λ.
The constant of proportionality b is given by 2.9×10-3 m.K, and the variable λ is the wavelength of a planet’s irradiation.
Therefore, planet 1has a surface temperature T = 2.9 x 10-3/ (4.908 x 10-6) K Ξ 590.87 K
Planet 5 has a surface temperature T = 2.9 x 10-3/ (1.2293 x 10-5) K Ξ 235.91 K
No-greenhouse temperature is defined as the temperature of a planet in the absence of infrared absorbers that include carbon dioxide and water droplets, among others. For planets 1 and 5, this temperature is equivalent to 570 and 228 degrees Celsius, respectively. In comparison with the surface temperatures of the planets (591o C and 236o C for planets 1 and 5, respectively), it is evident that the greenhouse gasses are responsible for the increased temperature.
The fact that there are differences between the no-greenhouse temperatures and the surface temperatures of the planets, it goes without saying that these planets are encapsulated by atmospheres. Nonetheless, planet 5 is likely to have a thicker atmosphere than the planet one because it is massive and far a distance from the sun. As such, this planet has a greater gravitational pull and hence, less likely to suffer from atmosphere escape, a function of temperature.
The gases that are more likely to form the atmospheres of planets 1 and 5 are the heavy gases that can withstand the escape velocity. These atmospheres are dominated by carbon dioxide gas, oxygen, methane, sulfur dioxide, ammonia, nitrogen, and water. The composition of the atmosphere is such that as one moves away from the sun, the more a planetary atmosphere is dominated by lighter gases. To this end, planet 1 is likely to be dominated by CO2 gas, while planet five is probably dominated by both nitrogen and ammonia.
Conclusion
It is improbable that one would visit the planet one because of the high temperatures and the lack of oxygen. Planet 5 is hospitable because it is more like the planet earth. It has enough oxygen, and the temperatures are favorable.
Planets 2 and 4 (Jovian planets)
For planet 2, the composition of hydrogen and helium as a fraction of the whole mass is approximately equal to 13/100 or 0.13. Similarly, for planet 4, this fraction accounts for approximately 0.13.
Planet 2 is likely to have metallic hydrogen liquid because it is relatively massive with respect to planet 4. Metallic hydrogen liquid is a function of pressure. As such, planet 2 is less likely to possess this metallic hydrogen liquid.
The surface temperature T= b/λ.
Therefore, for planet 2: T = 2.9 x 10-3/ (3.8555*10^-5) K Ξ 75.2 K
For planet 4: T = 2.9 x 10-3/ (8.7588*10^-5) K Ξ 33.1 K
The clouds surrounding these two planets are made up of hydrogen, helium, and their compounds. These are very colorful.
The moons are less likely to have atmospheres for the reason that they lack sufficient gravitational pull owing to their relatively small sizes.