Context:
Recently, NASA launched the first of two climate satellites aimed at studying heat emissions at Earth’s poles. The second satellite is set to be launched in the coming days. This mission, named PREFIRE (Polar Radiant Energy in the Far-InfraRed Experiment), focuses on understanding polar heat emissions.
Relevance:
GS III: Science and Technology
Dimensions of the Article:
- Significance of Measuring Heat Emissions at Earth’s Poles
- The PREFIRE Polar Mission Explained
Significance of Measuring Heat Emissions at Earth’s Poles:
Understanding Earth’s Energy Budget:
- Definition: Earth’s energy budget is the balance between incoming heat from the Sun and outgoing heat from Earth into space.
- Climate Impact: The difference between these two determines the planet’s temperature and climate.
Heat Emission Details:
- Arctic and Antarctic Emissions: A significant amount of heat from these regions is emitted as far-infrared radiation.
- Far-Infrared Radiation: Wavelengths range from 3 μm to 1,000 μm within the infrared spectrum.
Current Knowledge Gap:
- Measurement Limitations: There is currently no method to measure far-infrared radiation, creating a gap in understanding the planet’s energy budget.
CubeSats:
Basic Definition:
- Design: Miniature satellites with a 10 cm x 10 cm x 10 cm cube structure, known as “one unit” or “1U.”
- Weight: Each unit weighs no more than 1.33 kg.
- Size Configurations: Depending on the mission, CubeSats can be configured in sizes like 1.5, 2, 3, 6, and 12U.
Development and Purpose:
- Origin: Developed in 1999 by California Polytechnic State University at San Luis Obispo and Stanford University as educational tools.
- Advantages: Low cost and reduced mass compared to traditional satellites, making them suitable for technology demonstrations, scientific research, and commercial uses.
PREFIRE Mission CubeSats:
- Specifications: Each PREFIRE satellite is a 6U CubeSat, about 90 cm in height and 120 cm in width with deployed solar panels.
- Function: The solar panels provide necessary power for satellite operations.
Difference from SmallSats:
SmallSats Definition: Spacecraft with a mass less than 180 kilograms, roughly the size of a large kitchen fridge.
Variety in Size and Mass:
- Minisatellite: 100-180 kilograms
- Microsatellite: 10-100 kilograms
- Nanosatellite: 1-10 kilograms
- Picosatellite: 0.01-1 kilograms
- Femtosatellite: 0.001-0.01 kilograms
The PREFIRE Polar Mission Explained:
Overview:
- The PREFIRE (Polar Radiant Energy in the Far-InfraRed Experiment) polar mission comprises twin satellites, each equipped with an instrument, tasked with measuring the poles approximately six hours apart.
Objective:
- The primary goal of the mission is to unveil the complete spectrum of heat loss from Earth’s polar regions, thereby enhancing the accuracy of climate models.
Aim:
- The PREFIRE mission aims to fill knowledge gaps and furnish data to refine predictions related to climate change and sea level rise.
- It seeks to offer fresh insights into how Earth’s atmosphere and ice impact the radiation of heat from the Arctic and Antarctic into space.
Satellite Operation:
- Cube satellites, akin to the size of a shoebox, will be launched aboard an Electron launch vehicle.
- Equipped with Mars-tested technology, these satellites will measure an underexplored portion of Earth’s radiant energy.
- Twin satellites housing a thermal infrared spectrometer will orbit near-polar asynchronously, covering overlapping areas near the poles every few hours.
- Weighing less than 6 pounds (3 kilograms) each, the instruments will employ thermocouples, similar to those found in household thermostats, for data collection.
Mission Objectives:
- Understand the disproportionate warming of the Arctic compared to the rest of the planet since the 1970s.
- Gain insights into the efficiency of far-infrared heat emission by substances like snow and sea ice, and the influence of clouds on far-infrared radiation escaping to space.
- Enable researchers to forecast changes in heat exchange between Earth and space, and their repercussions on phenomena such as ice sheet melting, atmospheric temperatures, and global weather patterns.
-Source: Indian Express
