JUAN IN SPACE

Radiation and charged particles in space can be harmful to electronics, thus design mitigations should come into play. There are several sources of these elements in space, and we list out three of the most common sources. Sun Activity  Sun is basically a giant thermonuclear fusion reactor. Not only does it emit the Ultraviolet (UV) rays that you dread at noon, it also expels plasma at high velocity in  he name of solar wind. There are also these gigantic bursts erupting on the Sun's surface called solar flares. Sunspots serve as indicator for significant disturbances on the Sun. You can visit this link of you wish to see long-term historical record of solar activity from 1700. Galactic Cosmic Rays This is similar to the Sun's solar wind and activities, but coming from distant stars. Cosmic Rays are composed of many different elements such as Hydrogen, Helium and Carbon, and cover a very wide range of energies. They have sufficient energy to penetrate very ...

Satellites can also be endangered due to the presence of other satellites, space junks, and natural materials such as dust, comets or meteoroids. These floating objects can potentially collide, and with their high velocity movement, the impact will be severe.  Once a satellite is no longer functioning, it becomes a space debris or space junk. And right now, there may be hundreds of thousands pieces of space junks floating around. With these realization and challenge, responsible use of space is being actively promoted. Some satellites incorporate de-orbit mechanisms to prevent them from being an unwanted junk. Space Environment Vibration and Shock Gravity   Atmosphere Vacuum   Space junks Radiation and charged particles

Space is popular for its near-vacuum characteristic. However, along with this environment are potential issues with the satellite: Out-gassing From Earth's surface to space, pressure drops very significantly. This change of pressure can cause trapped gasses to be released, and these can re-condense to cause contamination or degradation of certain materials. While this is usually not a big issue, it can still affect delicate sensors and chips.  The concern on out-gassing is heightened when there are people involved, such as in the case of the ISS. A satellite bound for an ISS orbit stays in ISS for a certain duration (usually about a month). Since there are people living in the ISS, the released gasses can cause threat to their health. Cold Welding Moving parts in satellites such as deployment mechanisms entail challenges not only in the aspect of launch (vibrations and shock) but also in terms of successful operations (deployment). In vacuum, cold welding occurs...

Atmosphere affects satellites residing at the Low-Earth Orbit in the following ways: Drag Drag is a force that causes a satellite to fall back to Earth faster, shortening its lifetime. At less than 600 km from the Earth's surface, drag varies depending on how the atmosphere expands or contracts due to variations in solar activity. The impact of drag on the satellite also depends on the satellite's speed, size, shape and orientation. For instance, deployable panels can make the drag more prominent, leading to satellite's shorter lifetime. Atomic Oxygen Radiation and charged particles c an cause O 2 molecules to split apart in space, creating atomic oxygen, O. In this form, metal oxidation leading to corrosion or rusting becomes more intense. This can cause degradation of exposed areas and create issues with interconnects on solar arrays and on optical surfaces. Space Environment Vibration and Shock Gravity   Atmosphere Vacuum   Space junks R...

Contrary to what some people think, there is gravity in space only that it gets weaker with distance. Gravity is responsible for keeping the moon and other satellites orbit the Earth. However, it is also gravity that causes satellites, especially those near the Earth's surface to 'fall back' to Earth.  Slowly, as the satellite moves in space, it constantly gets pulled back to Earth. This event is aggravated by atmospheric drag, which is discussed in the next article. The closer a satellite is to the Earth's surface, expect that it will have a shorter lifetime. With this knowledge, you normally would want to bring your satellite to a higher altitude if you want it to stay in space for a longer time. Gravity can also help determine the amount of propellant that the spacecraft needs to move between orbits.  Space Environment Vibration and Shock Gravity  Atmosphere Vacuum   Space junks Radiation and charged particles References: NASA: What is Micr...

If you already tried riding an airplane, probably the most unforgettable moments of the ride would be the take-off and landing. During such times, you normally experience uncomfortable movements. It's not a perfect analogy, but basically, your satellite also experiences such uncomfortable movements during launch -- vibration and shock Vibration are relatively long-duration movements that occur during launch. There are several types of vibration that are attributed to various phenomena: Quasi-Static Acceleration attributed to: - Acceleration of the launch vehicle during launch - Low frequency vibrations due to staging effects Sinusoidal Vibration attributed to: - Structural response of the launch vehicle Random Vibration attributed to: - Aerodynamic events - Combustion phenomena Shock are short duration but high impact movements that occur due to the following: - Separation of fairing - Separation of other satellites on launcher - Separation of...

The 24th Session of the Asia-Pacific Regional Space Agency Forum (APRSAF-24) will be held in Bengaluru, India on November 14-17, 2017. This event is a good opportunity to meet space agencies, companies, universities and many other space-faring groups. You can learn a lot from attending this event, and even possibly find collaborators.  Last year, APRSAF was held in Manila, Philippines from November 15 to 18, 2016.  For more information on this event, you can visit their website .

The PHL-Microsat Program bagged the best paper award for their entry: Development of Deployable Antennas for Diwata-2 Microsatellite's Amateur Radio Payload during the COMNETSAT 2017 .  COMNETSAT is an IEEE sponsored International Conference on Communication, Networks and Satellite. The event is held annually and this year, it was held at Semarang, Indonesia. Image Courtesy of Ms. Salvatus Congratulations to the team!