The harsh realities of space that Chandrayaan 3 is built to brave

Subject :Science and technology

Section: Space technology

The Solar Wind and Spaceflight Challenges

Solar Wind and Earth’s Magnetic Field

The sun’s scorching hot surface emits a constant stream of charged particles known as the solar wind.
Solar wind includes protons and electrons moving at high speeds.
Earth’s magnetic field deflects and guides solar wind particles toward the magnetic poles.
Interaction of solar wind particles with oxygen and nitrogen in Earth’s upper atmosphere leads to collisions.
Oxygen and nitrogen atoms absorb electrons, releasing excess energy as photons (light) of different frequencies.
Oxygen contributes to green and orange hues, while nitrogen contributes to blues.
These interactions create the mesmerizing phenomenon of the northern lights.

Vulnerability of Spacecraft

Unlike on Earth, spacecraft lack natural protection from solar wind and other space hazards.
Spacecraft equipment must withstand impacts from solar wind particles to avoid catastrophic failure.
Example: Canada’s Anik E2 satellite experienced complete malfunction due to solar wind impact in 1982.

Solar Wind Effects on Electronics

Displacement Damage
- Result of charged particles displacing atoms in electronic chips.
- Leads to permanent chip performance decay.
- Caused by strong impacts from solar wind particles.
Single-Event Transients (SET)
- Temporary signal fluctuations due to solar wind particles.
- Corrupts transmitted messages momentarily.
- Example: Belgium’s 2003 election – a bit flip in a voting machine led to miscounted votes.

Radiation-Hardened Electronics

Engineers develop radiation-hardened electronics to safeguard spacecraft electronics from radiation effects.
Radiation-hardened design considers radiation levels during chip design, manufacturing, and packaging.
Multiple layers of protective measures are integrated into software and hardware components.
Triple modular redundancy (TMR) involves transmitting three identical signal copies.
In signal corruption (single-event transients), other uncorrupted signals can outvote the corrupted one.

Other Challenges and Safeguards

Instruments onboard spacecraft must withstand vibrations during launch from the launchpad.
Severe vibrations experienced during the launch process can affect instrument functionality.

Temperature Fluctuations and Material Challenges

Spacecraft in space face extreme temperature fluctuations.
Chandrayaan 3’s operational temperature range is -200°C to 200°C, depending on its position relative to the Moon and the Sun.
Extreme temperatures can lead to wire breakage, solder failure, and chip cracking.
Copper materials in solar panels can become more ‘active’ and seep through solar cells, affecting efficiency.
Outgassing occurs when some materials release trapped air molecules in a vacuum.
Example: Outgassed air molecules can deposit on a camera lens, affecting image quality.

Metal Coatings and Unexplained Problems

Some metal coatings form electrically conductive protrusions called whiskers.
Whiskers can short circuits and lead to satellite failures.
Whisker growth is attributed to built-up stress in the metal during vacuum conditions.
Expert selection and application of metal coatings are essential to prevent whisker-related issues.