JUAN IN SPACE

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!

We've mentioned in our previous article that Diwata-1 took an ISS orbit while Diwata-2 will be launched to a Sun-synchronous orbit. We've also mentioned that Agila-1 and Agila-2 were previously positioned to a certain degree of orbital slot.  But what are these things called orbit? Do I need to know these things? Why should I care? Orbit is the path followed by a satellite. You are probably aware that the moon orbits the Earth -- and moon is a natural satellite! There are several types of orbits, and each has their pros and cons. Let us take a look at some of the most common satellite orbits. Low Earth Orbit (LEO) Satellites in this orbit resides from 180 km to 3000 km from the Earth's surface. Due to its closeness to the surface, this orbit is easily accessible and launch opportunities are common, keeping the launch cost low. This orbit is popular for remote sensing applications since small and relatively less powerful cameras can work well from this dist...

Some satellites have an elliptical orbit. For these types of orbit, there are two commonly used terms: Apogee - This is the point at which the satellite is furthest from the Earth Perigee - This is the point at which the satellite is closest to the Earth   The terms apogee and perigee are specific to Earth. When the reference point is the Sun, these points are instead called aphelion and perihelion. The general term that describes these point is called apsis, and for any reference objects, the points are called apoapsis or apocenter and periapsis or pericenter. One important note is that the satellite travels more slowly at apogee than at any other point in orbit. Thus, when viewed from the Earth's surface, the satellite takes a long time to traverse the sky providing the user with a longer access or link time.

Just a year after acquiring Agila-1 , the Philippines acquired its second satellite, Agila-2. However, compared with Agila-1, Agila-2 is designed for a Philippine company and is not acquired while already in orbit. Agila-2 is a telecommunications satellite built by Space Systems/Loral (SS/L) for Mabuhay Satellite Corporation. It was launched to space from Xichang Satellite Launch Center via the Chang Zheng 3B rocket on August 19, 1997 (17:50 UTC) and was positioned at the 146°E longitude orbital slot. The mass varies from sources, but according to Gunter's Space, its launch mass is 3775 kg while its dry mass is 1800 kg (Wikipedia reports 2,820 kg launch mass). Agila-2 is claimed to be the most powerful telecommunications satellite in the entire Asia-Pacific region, and one of the most efficient in the industry. It carries 24 C-band, 24 Ku-band, and 6 extended C-band transponders, making it the satellite with the largest number of active transponders compared to any oth...

I am not sure how many of you is aware of this, but Diwata-1 is not the Philippines' first satellite. In 1996, Mabuhay Satellite Corporation under PLDT acquired Palapa B2-P, an Indonesian satellite that has been in space since March 20, 1987. From there, it was renamed to Agila-1 and became the Philippines' first satellite acquired while in orbit. Palapa B2-P was launched from Cape Canaveral aboard the Delta-3920 PAM-D rocket. It has a mass of 692 kg at the beginning of its life. It is a telecommunications satellite operating in the C-band - receiving from 5.925 GHz to 6.415 GHz and transmitting from 3.7 GHz to 4.2 GHz. Until the acquisition on 1996, it occupies the 113°E orbital slot. On August of the said year, it moved to its new orbital slot at 144°E. The Philippine's possession of the satellite was not long however, since it was deorbited 1998 - only more than a year after it was acquired. References: Gunter's Space Page: Palapa B1, B2, B2P, B2R, B4 ...

Everyone has their own mission in life, even a satellite. Well, harsh as it may sound but strictly speaking, a satellite exists only for the purpose of fulfilling its mission. And honestly, without a good mission, it is hard to get funding support for development and launch. Today, we will take a look at some common satellite mission categories. These categories also serve as satellite's classification by function which I mentioned in my previous post. Hopefully, this article will help us recognize the benefits of having a satellite. I mentioned before that space gives us opportunities to solve our problems, and these are some problems that satellite solve. I'm also actually paving the path for the sensitive topic of space economy and politics which I've been trying so hard to avoid, but well, we will get there. Haha. For now, here are your satellite missions. Communications Communication satellites dominate the space market. If you’ve watched NBA Live on your t...

There are many ways to classify satellites. These categories can be by function , by type of orbit or by mass. We will discuss satellite's functions and orbit in our next articles but for now, we will focus on satellite's classification by mass. Satellite's mass has direct impact on its cost, its development cycle and its launcher. The larger the satellite, the bigger is the development cost. This is because larger satellites carries more equipment such as redundancy modules, propellant, and more solar panels. Also, since it has more components and the lifetime and reliability expectation is higher, design reviews and tests conducted are also more than smaller satellites. Finally, larger satellites occupy larger space in the rocket, entailing higher launch cost. The names of the categories by mass is not an official convention. We can still, however use it for generic purposes: Large satellite - 1000 kg Medium-sized satellite - 500 kg to 1000 kg Small satellites...