📡 Technical Breakdown: The Pre-Launch Communication Link

zaasmi

@Danish-Bhatti said in 📡 Technical Breakdown: The Pre-Launch Communication Link:

The transfer of a satellite—such as the PakSat-MM1 or the iCube-Qamar—involves much more than just shipping a box. It is a multi-stage technical and diplomatic procedure.

In the high-pressure environment of a satellite launch, the “handshake” between SUPARCO and Chinese launch authorities (like CGWIC) is governed by specific technical protocols. These ensure that the satellite remains healthy and that the Pakistani controllers have full “visibility” of their asset while it sits on a Chinese rocket.

📡 Technical Breakdown: The Pre-Launch Communication Link

Before liftoff, a sophisticated data umbilical is established. This isn’t just a simple connection; it’s a high-speed, redundant system designed to manage the satellite’s “life support.”

1. Telemetry, Tracking, and Command (TT&C)

The core of the communication is the TT&C link. During the countdown:

The Umbilical: A physical cable (the umbilical) connects the satellite inside the rocket fairing to the ground support equipment (GSE).
Real-time Monitoring: SUPARCO engineers monitor critical health parameters such as battery voltage, internal temperature, and transponder status.
Protocol Standard: Most missions follow the CCSDS (Consultative Committee for Space Data Systems) standards, which allow different agencies (Pakistan and China) to share data packets seamlessly.

2. The Remote Mission Control Setup

While the rocket is in China, the mission is often shadowed by SUPARCO’s Mission Control Center (MCC) in Islamabad or Karachi.

Dedicated Leased Lines: High-security, low-latency fiber links or satellite relays connect the Chinese launch site (e.g., Xichang or Jiuquan) to Pakistan.
Data Mirroring: Every bit of telemetry received by the Chinese launch pad is mirrored to Pakistani screens, allowing local experts to give the final “Green Light” for their specific payload.

3. The “Aliveness” Sequence

Minutes before launch, the satellite undergoes an “Aliveness Test”:

Command Verification: A signal is sent from the ground to the satellite to confirm it can receive commands.
Internal Power Switch: The satellite is switched from “Ground Power” (provided by the launch pad) to “Internal Power” (its own batteries). This is a critical “Point of No Return.”

🛰️ Milestones: Pakistan’s Recent Orbital Fleet

The frequency of these transfers has increased as Pakistan builds out its “Vision 2047” space policy.

Satellite Name	Launch Site (China)	Key Technical Protocol	Status
PRSC-EO1	Jiuquan	Indigenous Electro-Optical Link	Active (Jan 2025)
PakSat-MM1	Xichang	SBAS (Augmentation System)	Active (May 2024)
HS-1	Jiuquan	Hyperspectral Data Stream	Active (Oct 2025)
PRSC-EO2	Sea-Launch	Mobile Sea-to-Ground Link	Active (Feb 2026)

⚠️ The “Safe Mode” Protocol

If a technical glitch occurs during the final 10 minutes of the countdown, the “Hold” protocol is triggered.

Automated Safing: The satellite is commanded into a low-power “Safe Mode.”
Nitrogen Purge: If the launch is scrubbed (canceled), nitrogen is pumped back into the fairing to keep the Pakistani hardware cool and dry.
Data Lock: All communication is encrypted to ensure that the sensitive technical specs of Pakistan’s imaging or communication tech remain confidential during troubleshooting.

Would you like to detail the specific orbital insertion maneuvers that happen once the satellite separates from the Chinese rocket?

zaasmi

said in 📡 Technical Breakdown: The Pre-Launch Communication Link:

Would you like to detail the specific orbital insertion maneuvers that happen once the satellite separates from the Chinese rocket?

When the Long March rocket reaches its target altitude, the most delicate part of the journey begins: The Separation and Orbital Insertion. This is where the satellite transforms from “cargo” into an independent spacecraft.

Here is the step-by-step technical breakdown of how a Pakistani satellite (like PakSat-MM1 or HS-1) finds its home in the stars.

🛰️ Phase 1: The “Clean” Separation

At the precise second of orbital injection, the rocket’s computer triggers the separation sequence.

Pyrotechnic Bolts/Clamps: Explosive bolts or motorized clamps release the satellite from the rocket’s payload adapter.
Spring Ejection: Heavy-duty springs push the satellite away from the upper stage at a specific velocity (usually around to m/s) to ensure there is no “re-contact” between the rocket and the satellite.
The “Tumble” Control: Small thrusters on the satellite immediately fire to stop any spinning caused by the separation, a process called Detumbling.

🔥 Phase 2: Orbit Raising (The Hohmann Transfer)

Most Pakistani satellites are launched into a Geostationary Transfer Orbit (GTO)—an elliptical path that is not yet their final home. To reach a circular Geostationary Orbit (GEO) at 36,000 km, the satellite must perform several “burns.”

Apogee Kick Motor (AKM) Firing: When the satellite reaches the highest point of its ellipse (the apogee), its internal engine fires to increase its velocity.
Circularization: This maneuver changes the orbit from an egg-shape to a perfect circle.
Inclination Correction: Since China’s launch sites are at a different latitude than the equator, the satellite must “tilt” its orbital plane to sit directly above the Earth’s equator.

Technical Note: This process uses the Hohmann Transfer Orbit principle, calculated using the change in velocity, known as Delta-V ().

🛠️ Phase 3: Deployment and Testing

Once the final orbit is reached, the satellite “wakes up” fully.

Solar Array Deployment: The folded solar panels unfurl like wings to begin generating power from the sun.
Antenna Deployment: Communication dishes open up to start sending and receiving signals from SUPARCO ground stations.
Station Keeping: The satellite uses its thrusters to fight “orbital drift” caused by the gravity of the moon and sun, keeping it locked at its assigned longitude (e.g., 38.2° East for PakSat-MM1).

📋 The “First Light” Checklist

Task	Description	Timeframe
LEOP	Launch and Early Orbit Phase; high-intensity monitoring.	Days 1–10
IOT	In-Orbit Testing; checking if all transponders/cameras work.	Weeks 2–6
Handover	Official transfer of control from the launch team to SUPARCO.	Month 2

❓ FAQ: Post-Launch

Q: What happens if the satellite misses its target orbit?
A: If the rocket under-performs, the satellite can use its own fuel to “make up the difference,” though this shortens the satellite’s total lifespan (usually 15 years) because it uses up its station-keeping propellant.

Q: Can SUPARCO see the satellite immediately after separation?
A: Yes. As soon as the satellite separates, it begins “shouting” a beacon signal. Ground stations in Karachi and Islamabad, along with Chinese tracking ships in the ocean, listen for this “first breath.”

Would you like to see a comparison of the different propulsion systems (Chemical vs. Electric) used by these satellites to stay in orbit?

zaasmi

said in 📡 Technical Breakdown: The Pre-Launch Communication Link:

Would you like to see a comparison of the different propulsion systems (Chemical vs. Electric) used by these satellites to stay in orbit?

Once a Pakistani satellite reaches its target orbit, its survival depends on its Propulsion System. For decades, satellites used liquid chemicals (combustion), but recent missions like PakSat-MM1 and the newest PRSC series are increasingly moving toward Electric Propulsion (EP).

Think of it as the difference between a high-octane drag racer and a solar-powered marathon runner.

🏎️ Chemical Propulsion: The “Old Guard”

Chemical propulsion relies on a rapid exothermic reaction (combustion) of fuel and an oxidizer.

How it works: Liquid propellants (like Hydrazine) are mixed and ignited, shooting hot gas out of a nozzle.
Best For: Fast maneuvers, like the initial “Apogee Kick” to get into orbit or rapid collision avoidance.
The Downside: It’s heavy. Half the weight of a traditional satellite is often just the fuel tank.

⚡ Electric Propulsion (Ion/Hall Thrusters): The “New Frontier”

Electric propulsion uses electricity from the satellite’s solar panels to accelerate gas (typically Xenon or Argon) using magnetic or electric fields.

How it works: It strips electrons from atoms to create ions, then uses a high-voltage grid to “spit” them out at incredible speeds—up to m/s.
Best For: Long-term “Station Keeping” (staying in the right spot) and deep-space missions.
The Downside: The thrust is tiny (about the weight of a sheet of paper), so it takes months to change an orbit.

📊 Side-by-Side: Which is Better for Pakistan?

Feature	Chemical Propulsion	Electric Propulsion (EP)
Thrust Level	High (Instant speed)	Low (Gradual speed)
Fuel Efficiency	Low (s)	Extreme (–s)
Mission Life	10–15 years (Fuel limited)	20+ years (Efficiency limited)
Launch Weight	Very Heavy (Bulky tanks)	Light (Saves 30–50% mass)
Primary Use	Launch/Orbit Insertion	Orbit Maintenance/Station Keeping

The “Hybrid” Strategy

Most modern SUPARCO satellites now use a Hybrid System:

Chemical: For the fast ride from the rocket drop-off point to the Geostationary belt.
Electric: Once parked, it switches to electric thrusters for the next 15 years to stay perfectly aligned with Pakistan’s ground stations. This allows the satellite to carry more “Payload” (better cameras and more transponders) instead of heavy fuel.

❓ FAQ: The Future of SUPARCO’s Engines

Q: Does Electric Propulsion work in a vacuum?
A: It only works in a vacuum. The thrust is so low that even a tiny bit of air resistance on Earth would stop it from moving.

Q: Is Xenon fuel expensive?
A: Yes, Xenon is rare and can cost over $3,000/kg. However, because the system is so efficient, you only need a small amount compared to tons of chemical fuel.

Q: Can we see these thrusters firing?
A: Chemical thrusters produce a visible flame. Electric thrusters produce a ghostly blue or violet glow (plasma), which is often captured by “Selfie-Cams” on modern satellites.

Lovely queen

said in 📡 Technical Breakdown: The Pre-Launch Communication Link:

said in 📡 Technical Breakdown: The Pre-Launch Communication Link:

Would you like to see a comparison of the different propulsion systems (Chemical vs. Electric) used by these satellites to stay in orbit?

Once a Pakistani satellite reaches its target orbit, its survival depends on its Propulsion System. For decades, satellites used liquid chemicals (combustion), but recent missions like PakSat-MM1 and the newest PRSC series are increasingly moving toward Electric Propulsion (EP).

Think of it as the difference between a high-octane drag racer and a solar-powered marathon runner.

🏎️ Chemical Propulsion: The “Old Guard”

Chemical propulsion relies on a rapid exothermic reaction (combustion) of fuel and an oxidizer.

How it works: Liquid propellants (like Hydrazine) are mixed and ignited, shooting hot gas out of a nozzle.

Best For: Fast maneuvers, like the initial “Apogee Kick” to get into orbit or rapid collision avoidance.

The Downside: It’s heavy. Half the weight of a traditional satellite is often just the fuel tank.

⚡ Electric Propulsion (Ion/Hall Thrusters): The “New Frontier”

Electric propulsion uses electricity from the satellite’s solar panels to accelerate gas (typically Xenon or Argon) using magnetic or electric fields.

How it works: It strips electrons from atoms to create ions, then uses a high-voltage grid to “spit” them out at incredible speeds—up to m/s.

Best For: Long-term “Station Keeping” (staying in the right spot) and deep-space missions.

The Downside: The thrust is tiny (about the weight of a sheet of paper), so it takes months to change an orbit.

📊 Side-by-Side: Which is Better for Pakistan?

Feature Chemical Propulsion Electric Propulsion (EP)

Thrust Level High (Instant speed) Low (Gradual speed)

Fuel Efficiency Low (s) Extreme (–s)

Mission Life 10–15 years (Fuel limited) 20+ years (Efficiency limited)

Launch Weight Very Heavy (Bulky tanks) Light (Saves 30–50% mass)

Primary Use Launch/Orbit Insertion Orbit Maintenance/Station Keeping

The “Hybrid” Strategy

Most modern SUPARCO satellites now use a Hybrid System:

Chemical: For the fast ride from the rocket drop-off point to the Geostationary belt.

Electric: Once parked, it switches to electric thrusters for the next 15 years to stay perfectly aligned with Pakistan’s ground stations. This allows the satellite to carry more “Payload” (better cameras and more transponders) instead of heavy fuel.

❓ FAQ: The Future of SUPARCO’s Engines

Q: Does Electric Propulsion work in a vacuum?
A: It only works in a vacuum. The thrust is so low that even a tiny bit of air resistance on Earth would stop it from moving.

Q: Is Xenon fuel expensive?
A: Yes, Xenon is rare and can cost over $3,000/kg. However, because the system is so efficient, you only need a small amount compared to tons of chemical fuel.

Q: Can we see these thrusters firing?
A: Chemical thrusters produce a visible flame. Electric thrusters produce a ghostly blue or violet glow (plasma), which is often captured by “Selfie-Cams” on modern satellites.

Would you like to explain how the “Solar Arrays” on these satellites are designed to power such high-energy electric thrusters?

zaasmi

@Lovely-queen said in 📡 Technical Breakdown: The Pre-Launch Communication Link:

Would you like to explain how the “Solar Arrays” on these satellites are designed to power such high-energy electric thrusters?

To run a high-efficiency electric engine in the freezing vacuum of space, a satellite needs a massive, reliable power source. Since there are no gas stations in orbit, Pakistani satellites like PakSat-MM1 rely on advanced Solar Array technology to harvest energy from the sun.

☀️ The Powerhouse: Multi-Junction Solar Cells

Unlike the silicon panels on a house roof (which are about 20% efficient), space-grade panels use Multi-Junction (MJ) cells.

Layered Design: These cells are made of different materials (like Gallium Arsenide and Germanium) stacked on top of each other.
The Spectrum Catch: Each layer is “tuned” to catch a different color of sunlight. The top layer catches blue light, the middle catches green/yellow, and the bottom catches infrared.
Efficiency: This allows them to reach efficiencies of 30% to 35%—critical when every square inch of the satellite’s surface is precious “real estate.”

🔌 From Sunlight to Plasma: The Power Flow

The process of turning a photon into thrust is a complex engineering feat managed by the Power Processing Unit (PPU).

Collection: Solar arrays (some spanning over 25 meters, like those on the PakSat-MM1) collect DC electricity.
Regulation: The PPU acts as the “brain,” stabilizing the voltage.
The “Kick”: For Electric Propulsion, the PPU must boost the voltage to roughly 300V to 800V.
Ionization: This high-voltage electricity is used to strip electrons off Xenon atoms, turning them into a glowing blue plasma that is then accelerated out of the thruster to move the satellite.

📊 Solar vs. Battery: The Day/Night Cycle

Satellites in Geostationary orbit spend most of their time in the sun, but they do face “Eclipse Seasons” where the Earth blocks the sun for up to 72 minutes.

Component	Role during “Day” (Sunlight)	Role during “Eclipse” (Shadow)
Solar Arrays	Powering the satellite + Charging batteries.	Offline (No power generation).
Batteries	Storing excess energy.	Providing 100% of power to keep the satellite “alive.”
Thrusters	Operating at full power for maneuvers.	Usually Powered Down to save battery life.

🛠️ Design Feature: Radiation Hardening

In space, solar panels are constantly bombarded by high-energy particles (Radiation).

Cover Glass: Each cell is protected by a thin layer of “Ceria-doped” glass to prevent the sun’s UV rays and cosmic radiation from “fogging” the panels.
Degradation: Engineers expect a satellite to lose about 1% of its power every year due to radiation damage. A satellite designed for a 15-year mission starts its life with much more power than it actually needs to account for this “wear and tear.”

❓ FAQ: Solar Power in Space

Q: Do the solar panels follow the sun?
A: Yes. Most Pakistani satellites use Solar Array Drive Assemblies (SADA)—motorized hinges that slowly rotate the panels so they always face the sun directly, even as the satellite moves.

Q: What happens if a panel fails to unfurl?
A: This is a “mission critical” failure. To prevent this, SUPARCO uses redundant springs and “burn wires” (small heaters that melt a plastic restraint) to ensure the panels pop open once the satellite is in space.

Q: Can solar panels be used to recharge the “fuel”?
A: No. Solar panels only provide the energy to push the fuel (Xenon). Once the Xenon gas is gone, the satellite’s mission ends, even if the solar panels are still working perfectly.

Would you like to learn about the “End of Life” protocol—how SUPARCO moves these satellites into a “Graveyard Orbit” once their fuel finally runs out?

zaasmi

said in 📡 Technical Breakdown: The Pre-Launch Communication Link:

Would you like to learn about the “End of Life” protocol—how SUPARCO moves these satellites into a “Graveyard Orbit” once their fuel finally runs out?

When a satellite like the PakSat-MM1 reaches the end of its 15-year lifespan, it doesn’t just “turn off” and drift. To prevent it from becoming a dangerous piece of space junk that could collide with active satellites, SUPARCO follows international protocols to move it to a Graveyard Orbit.

Here is how Pakistan and China plan for the “retirement” of their orbital fleet.

🪦 The Graveyard Orbit (Supersynchronous Orbit)

For Geostationary (GEO) satellites, returning to Earth is not an option—it would require too much fuel to slow down. Instead, they are pushed outward.

The Location: The graveyard orbit is located approximately 300 km above the functional Geostationary belt (which is at 35,786 km).
The Math: Pushing a satellite up into the graveyard requires only about 11 m/s of velocity change (), whereas bringing it down to burn up in the atmosphere would require a massive 1,500 m/s.
The Room: Space is vast. If we space retired satellites 100 km apart, we could fit thousands of them in this “junk orbit” without them ever touching.

🛠️ The 3-Step Decommissioning Process

Once SUPARCO and Chinese partners determine a satellite has reached its “End of Life” (EOL), they execute a final mission plan.

1. The Final “Re-boost”

Before the fuel runs out completely, engineers use the last remaining drops of propellant (Chemical or Electric) to fire the thrusters one last time. This raises the perigee (the lowest point of the orbit) safely above the active GEO ring.

2. Passivation (Making it “Safe”)

A “dead” satellite with full batteries or pressurized tanks is a ticking time bomb—it could explode and create thousands of pieces of debris. Passivation involves:

Venting Propellant: Emptying all fuel tanks and pressurized gases into space.
Discharging Batteries: Depleting the chemical energy in the batteries so they don’t short-circuit or explode.
Power Down: Permanently disconnecting the solar arrays from the internal electronics.

3. The “Silent Drift”

Once passivated, the satellite becomes an inert “hunk of metal.” Because there is no air in space to slow it down, it will stay in the graveyard orbit for millions of years, circling the Earth as a silent monument to Pakistan’s space history.

🌍 Responsibility and “Space Ethics”

Pakistan adheres to the IADC (Inter-Agency Space Debris Coordination Committee) and United Nations guidelines.

The “25-Year Rule”: For Low-Earth Orbit (LEO) satellites (like the PRSC imaging series), the rule is different. Instead of a graveyard, they are lowered into the atmosphere to burn up within 25 years of their mission ending.

📊 Decommissioning Comparison

Satellite Type	Final Destination	Time to “Disappear”
LEO (Imaging)	Atmospheric Re-entry	< 25 Years (Burns up)
GEO (Communication)	Graveyard Orbit	Millions of Years (Drifts)
Deep Space (Lunar)	Solar Orbit / Moon Impact	Permanent

❓ FAQ: The End of an Era

Q: What happens if a satellite dies suddenly before it can be moved?
A: This is a major concern. If a satellite loses power unexpectedly, it becomes “trapped” in the active orbit. This is why SUPARCO monitors “Fuel Gauges” very closely and usually begins the move while there is still a small safety margin of fuel left.

Q: Can we go up and “tow” a dead satellite away?
A: Currently, “Space Tugs” are being developed by companies in the US and China. In the future, Pakistan might hire a service to “refuel” an old satellite or tow it to the graveyard if it breaks down prematurely.

Q: Has any Pakistani satellite reached the graveyard yet?
A: Yes, older generations like Badr-B and the original PakSat-1 (which was a leased satellite moved to Pakistan’s slot) have already completed their missions and paved the way for the high-tech fleet we see today.

Would you like to summarize this entire “Satellite Journey”—from the factory in China to the Graveyard Orbit—into a single infographic-style timeline for your article?

zaasmi

said in 📡 Technical Breakdown: The Pre-Launch Communication Link:

Would you like to summarize this entire “Satellite Journey”—from the factory in China to the Graveyard Orbit—into a single infographic-style timeline for your article?

To wrap up our exploration, let’s visualize the entire journey of a Pakistani satellite. This “Cradle-to-Grave” timeline summarizes the collaboration between SUPARCO and China, from the initial blueprints to the final drift in the graveyard orbit.

🛰️ Infographic: The Lifecycle of a Pakistani Satellite

Phase 1: Birth & Earthbound Journey

Design (Years 1-3): SUPARCO engineers collaborate with Chinese specialists to design the payload (cameras/transponders) and the bus (the satellite body).
Assembly & Testing: The satellite is built in a sterile “Clean Room.” It undergoes “Shake & Bake” tests to simulate the violence of a rocket launch.
The Transfer: The satellite is placed in a nitrogen-purged container and flown via specialized cargo jet from Pakistan to a Chinese launch hub (Xichang, Jiuquan, or Hainan).

Phase 2: The Ascent

Integration: In China, the satellite is mated to a Long March rocket.
Launch: Ignition! The rocket carries the satellite through the atmosphere.
Separation: At the correct altitude, the satellite is “pushed” away from the rocket stage.
First Breath: The satellite unfurls its solar arrays and sends its first “heartbeat” signal back to ground stations in Karachi and Islamabad.

Phase 3: Operational Life (The “Prime” Years)

IOT (In-Orbit Testing): For the first 2 months, every system is checked.
Utilization (Years 1-15): The satellite performs its mission—providing 5G internet, monitoring floods, or aiding national security.
Station Keeping: Small electric or chemical thrusters fire regularly to keep the satellite from drifting out of its “parking spot.”

Phase 4: Retirement (The Graveyard)

End-of-Life Maneuver: With the last 1% of its fuel, the satellite is commanded to climb 300 km higher than its working orbit.
Passivation: All remaining energy is drained, and fuel tanks are vented to prevent accidental explosions.
The Eternal Drift: The satellite becomes a permanent, silent part of the “Graveyard Orbit,” ensuring the active space lanes remain clear for the next generation of Pakistani satellites.

Summary Table: The Evolution of Pakistan’s Fleet

Satellite Era	Key Technology	Launch Partner	Final Status
Badr Series (1990s)	Basic Radio	China / Russia	Re-entered Atmosphere
PakSat-1R (2011)	Digital Comm.	China (Xichang)	Active / Approaching EOL
PRSS-1 (2018)	High-Res Imaging	China (Jiuquan)	Active
PRSC-EO2 (2026)	Advanced EO	China (Sea-Launch)	Just Launched

Ehsan Malik

From SUPARCO to the Stars: The Life and Legacy of Pakistan’s Satellite Fleet

nazirkhan engineer

@Ehsan-Malik said in 📡 Technical Breakdown: The Pre-Launch Communication Link:

From SUPARCO to the Stars: The Life and Legacy of Pakistan’s Satellite Fleet

From SUPARCO to the Stars: The Life and Legacy of Pakistan’s Satellite Fleet

Published: February 2026

Category: Aerospace & Technology

Reading Time: 8 Minutes

The successful launch of the PRSC-EO2 on February 12, 2026, marks another milestone in the “all-weather” friendship between Pakistan and China. But what does it actually take to get a satellite from a lab in Islamabad to a stable orbit 36,000 km above the Earth?

In this article, we explore the high-stakes journey of a Pakistani satellite—from its birth to its final “retirement” in the graveyard orbit.

🏗️ Phase 1: The Logistics of Sovereignty

Before a satellite reaches the launch pad at Xichang or Jiuquan, it undergoes a rigorous “Transit Campaign.”

Clean Room Certification: Satellites are tested for “vibration” (to survive the rocket) and “thermal vacuum” (to survive space).
The Secure Transfer: High-value hardware is transported via chartered cargo aircraft in nitrogen-purged containers. This bypasses standard customs to ensure the technology remains secure and pristine.
The Chinese Handshake: Upon arrival, Pakistani engineers from SUPARCO and Chinese teams from CGWIC conduct “aliveness tests” to confirm no damage occurred during flight.

🚀 Phase 2: The Ascent and “First Breath”

Once encapsulated in the fairing of a Long March rocket, the satellite enters the most dangerous minutes of its life.

Separation: At the target altitude, pyrotechnic bolts release the satellite.
Detumbling: Small thrusters fire immediately to stop the satellite from spinning.
Solar Deployment: Like wings, the Multi-Junction solar arrays unfurl. These advanced panels are over 30% efficient, converting sunlight into high-voltage electricity to power the onboard systems.

⚡ Phase 3: The Engine Room (Chemical vs. Electric)

Modern Pakistani satellites, such as the PakSat-MM1, utilize a “Hybrid” propulsion strategy to maximize their lifespan.

Chemical Thrust: Used for the initial “heavy lifting” to reach the correct orbital slot.
Electric Propulsion (EP): Once in place, Ion or Hall Thrusters take over. These use solar energy to accelerate Xenon gas at speeds up to 40,000 m/s. While the thrust is gentle, it is incredibly efficient, allowing satellites to stay operational for 15–20 years.

🪦 Phase 4: The Final Goodbye (The Graveyard Orbit)

Pakistan adheres to international “Space Ethics.” When a satellite reaches the end of its life, it isn’t left to drift in active lanes.

The 300km Boost: Using its final drops of fuel, the satellite climbs to a Graveyard Orbit safely above the active Geostationary belt.
Passivation: Engineers drain the batteries and vent the tanks to prevent accidental explosions, leaving the satellite as a silent, safe monument in the stars.

📊 Quick Reference: The Evolution of the Fleet

Mission	Launch Date	Purpose	Tech Highlight
PakSat-1R	2011	Communication	First major GEO collab
PRSS-1	2018	Remote Sensing	Dual-satellite launch
PakSat-MM1	2024	Broadband	Hybrid Propulsion
PRSC-EO2	2026	Earth Observation	Sea-based Launch

❓ Frequently Asked Questions (FAQ)

Who controls the satellite? > While China provides the launch vehicle, the “steering wheel” belongs to Pakistan. Ground stations in Karachi and Islamabad manage daily operations.
What is the “25-Year Rule”? > For Low-Earth Orbit satellites, they must be designed to burn up in the atmosphere within 25 years of their mission ending to keep space clean.

Looking Forward

As SUPARCO looks toward Vision 2047, the collaboration with China remains the backbone of Pakistan’s presence in the final frontier. From the sea-borne launches of 2026 to future lunar exploration, the journey is only just beginning.