3-Feb-2023: Space debris identified by India

Government of India has announced that 111 payloads and 105 space debris have been identified as Indian objects orbiting Earth. All orbiting debris will affect the future of outer space and future missions. ISRO has also been carrying out several studies on the impact of growing space debris on the space environment.

Space debris are man-made objects in Earth's orbit that no longer serve a useful purpose. These include defunct satellites, spent rocket stages, and fragments of debris from collisions or other events.

Potential hazards:

• Threat for Operational Satellites: Collisions with debris can leave satellites dysfunctional
• Kessler Syndrome: Overpopulation of space with debris
• Reduction of Orbital Slots: Accumulation of debris can limit availability of desirable orbital slots
• Space Situational Awareness: Tracking and predicting orbits becomes more challenging

Initiatives to curb space debris:

India:

• In 2022, ISRO set up the System for Safe and Sustainable Operations Management(IS 4 OM): Monitors objects posing collision threats, predicts evolution of debris, and mitigates risk.
• 21 collision avoidance manoeuvres carried out in 2022 to avoid collisions with other space objects.
• Centre for Space Debris Research: Monitors and mitigates debris threat
• Project NETRA: An early warning system to detect debris and other hazards to Indian satellites

Global:

• Inter-Agency Space Debris Coordination Committee (IADC): An international forum to coordinate efforts between spacefaring nations to address debris issue
• The United Nations has established the Committee on the Peaceful Uses of Outer Space (COPUOS): Develops guidelines for long-term sustainability of outer space activities, including debris mitigation
• ESA Clean Space initiative: reduces amount of debris and promotes sustainable space activities

Solutions:

• Reusable Launch Vehicles to reduce the number of new debris generated from launches.
• Improved Tracking and Monitoring mitigates risks to operational satellites and human space missions.
• Materials and Design Improvements using more durable materials and designing satellites for eventual de-orbiting can reduce the number of debris generated in long term.

28-Jan-2023: Visible Line Emission Coronagraph (VLEC), the primary payload on board Aditya-L1, was handed over to ISRO by the Indian Institute of Astrophysics (IIA).

VELC Payload:

• Main payload among seven designed to study various aspects of the Sun
• Designed in 15 years, one of the most precise instruments made in India
• Significance
  • Helps study temperature, velocity and density of corona
  • Understand processes that result in heating of corona and acceleration of solar wind
  • Aid studies on drivers of space weather
  • Measures magnetic field of corona
  • Study development and origin of coronal mass ejection

India's First Solar Mission (Aditya-L1)

• To be Launched using Polar Satellite Launch Vehicle (PSLV)
• 7 payloads (instruments) will be on board
  • VELC (Visible Line Emission Coronagraph) - primary payload
  • Solar Ultraviolet Imaging Telescope (SUIT)
  • Solar Low Energy X-ray Spectrometer (SoLEXS)
  • Aditya Solar wind Particle Experiment (ASPEX)
  • High Energy L1 Orbiting X-ray Spectrometer (HEL1OS)
  • Plasma Analyser Package for Aditya (PAPA)
  • Advanced Tri-axial High Resolution Digital Magnetometers

Objective:

• Study the Sun’s corona, photosphere, chromosphere, solar emissions, solar winds, flares and Coronal Mass Ejections (CMEs)
• Carry out round-the-clock imaging of the Sun

L1 (Lagrangian/Lagrange Point 1)

• Position in space where the gravitational forces of a two-body system produce enhanced regions of attraction and repulsion
• Aditya-L1 will be launched to L1 orbit which is about 1.5 million km from Earth
• Allows Aditya-L1 to continuously view the Sun without any occultation/eclipses
• Home to the Solar and Heliospheric Observatory Satellite (SOHO)

Other Missions to the Sun:

• NASA's Parker Solar Probe
• Helios 2 Solar Probe
• Solar Orbiter

Other active spacecraft monitoring the Sun: Advanced Composition Explorer (ACE), Interface Region Imaging Spectrograph (IRIS), WIND, Hinode, Solar Dynamics Observatory, and Solar Terrestrial Relations Observatory (STEREO).

Read more ...