summary task
. Task 1. Secondary Research
1.1. Preparation of rocket fuel and its difficulties
In aerospace industry, the use of solid rocket propellant showed its effectiveness, ability to be storable, and compact propulsion system. As it known that old solid propellant has reduced performance; a rocket propellant’s increasing age increases surface area and also, consequently, its burn rate. However, Arizona State University researchers discovered unexplained significant number of motors failures despite avoiding old propellant. Their solid fuel was created with old components, and no documentation had existed regarding this problem. Even though that the cost of the old chemicals in the solid propellant is competitive against alternative solid or liquid rocket propellants, the aerospace engineers should be cautious in using old chemicals because of its unpredictable nature in new propellants.
Liquid hydrogen fuel is considered an alternative fuel of rocket propulsion systems. Liquid hydrogen is can be consider as good choice, knowing that it can be made from renewable energy and it doesn’t produce emissions. However, some grounded tests were done, it was conducted to observe rocket engine with no occurred launch. The results show that liquid hydrogen consider a safety hazard. Leakage of hydrogen can lead to combust, emergency situation will occurs if hydrogen and oxygen tanks burst, and one of the important hazardous is the mixture of hydrogen-air and hydrogen-oxygen. These results show that liquid hydrogen consider to be a safety issue.
1.2. Preparation and safety for radiation
Radiation has some major impacts on the human life and it considered r one of the biggest challenging among the other space hazards. The human mission to explore space is hindered by the difficulty to visualize since the space radiations are invisible to the human eye. The radiation effect the human body with many diseases, such as, damages the central nervous system, and increases the risk of cancer and NASA has explored and documented the effects on biological samples caused by radiation. Even thought that space station is located within the protective magnetic field of the earth. This implies that astronauts are exposed to several higher radiations, it is still a lesser dose compared to what is kept by the deep space. To reduce the effects of radiation, rockets and deep space vehicles should have considerable alerts, dosimetry, and protective shielding such as graphene.
As it is known that exposing to high-level radiation and having no atmosphere will prevent humans to be a live on Mars for example. So, shelter or space suit is one of the important aeronautical engineering materials when it comes to space travel. Recent research shows that, at standard conditions, graphene seems to be a promising shielding material when compared with other materials, its ability of diminishing space explorer introduction to unsafe radiation during travel makes it fundamental material in designing and building shelters and spacesuit.
1.3. Human safety in space
Through the research conducted, it has been clear that space travel is associated with microgravity, psychic stress, weak immune system, and other diseases. As a result of long space travel, the human body tries to make some adjustments to the new space environments. The changes in how immunity functions are affected can be attributed to the alterations of various levels of some hormones in the human body. These changes, in turn, have been attributed to the weakening of the human immune system. Also, space travel has impaired the human immune system as a result of exposer to concentrated radiations that leads to an imbalanced response to the body to various human diseases such as cancer. In a nutshell, a long duration of space travel has led to the dysfunction of the immune system inefficiency to function normally. It is very clear that further studies are needed for space travel, for the safety of the astronauts before, during, and after the long-term space travel.
1.4. The Potential shielding effect of a graphene space suit (Need to be revised by Abdullah)
With the development of human society and the advancement of science, space travel will often be mentioned in the future. Fortunately, we are already studying the security issues needed for space travel. This part discusses the selection of spacesuit materials and their safety.
As it is known to us, solar radiation can have a terrible influence on the human body. For example, an important environmental factor that may interact synergistically with cosmic radiation is sleep deprivation. Thus, the essential thing for astronauts is how to protect humans from exposure to high-level radiation. To find out the materials which offer an excellent shield to reduce the radiation intensity. After reading the peer-reviewed article, there are 32 kinds of materials have been tested during the experiment. The experiment uses a radiation modeling tool to investigate thirty-two potential shielding materials. It simulated environment is that radiation exposure during the return to Mars is estimated to be 360 days. Each substance's ability to reduce the radiation dose received by computer phantoms in the stars' cosmic radiation was evaluated. (Squire, Buchanan, and Elsaleh).
The experiment shows that Graphene consists of a hexagonal network of carbon atoms and has many favorable attributes, including immense strength, flexibility, and heat conductivity. It could be made into fibers to create a material suitable to be worn during transit. There was a significant dose reduction when the graphene material was simulated around the phantom within the spacecraft.
The conclusion is that a graphene-based astronaut suit could diminish space explorer's intake of dangerous radiation during travel to Mars. A tornado cellar utilizes fuel as a hindrance, likewise, diminished the radiation portion during a solar particle event (Squire, Buchanan, and Elsaleh). In the future, we can continue applying Graphene as the primary materials when building and designing new shelters and spacesuit.