Question: Sentinel-6, which has been launched recently as joint effort of US-European space program, is a-
a) Military satellite
b) Navigational Satellite
c) Space Telescope
d) Global Ocean Monitor
Answer: (d)
Related Facts:
- On November 21, 2020, the Sentinel-6 a US-European satellite was launched to undertake measurements regarding global sea level rise.
- The satellite was projected into the orbit by SpaceX Falcon 9 rocket, from California’s Vandenberg Air Force base.
- The Sentinel-6 Michael Freilich satellite after acquiring its orbit deployed its solar panels and made the first contact with controllers at a ground station in Alaska.
- NASA has renamed this key ocean observation satellite in honor of Earth scientist Michael Freilich, who retired last year as head of NASA’s Earth Science division, a position he held since 2006.
Description of the Satellite:
- Sentinel-6 is actually a series of two satellites Sentinel-6a and Sentinel-6b
- The present one is Sentinel-6a, the first of two identical satellites — the second to be launched in five years.
- Sentinel-6b will provide measurements of unprecedented precision until at least 2030.
- The twin satellites will measure sea-level rise, tracking changes threatening to disrupt tens of millions of lives within a generation.
- Each Sentinel-6 probe carries a radar altimeter, which measures the time it takes for radar pulses to travel to Earth’s surface and back again.
- The satellites will circle the planet in the same orbit as earlier missions that supplied sea-surface height data over the last three decades, mapping 95 percent of Earth’s ice-free ocean every ten days.
- The satellite’s main instrument is an extremely accurate radar altimeter that will bounce energy off the sea surface as it sweeps over Earth’s oceans.
- In the next launch Sentinel-6B will ensure continuity of the record.
- The Sentinel satellites are each about the size and shape of a large minivan topped with slanted solar panels and weigh nearly 1,200 kilos, including rocket fuel.
- They are designed to last for five-and-a-half years but could provide data for far longer.
- Europe and the United States are sharing the $1.1 billion (900 million euro) cost of the mission, which includes the twin satellite.
Sea level rise a grave problem:
- Nearly 800 million people live within five metres of sea level, and even an increase in sea level of a few centimeters can translate into vastly more damage from high tides and storm surges.
- Sea-surface heights are affected by heating and cooling of water, allowing scientist to use the altimeter data to detect such weather-influencing conditions as the warm El Nino and the cool La Nina.
- The measurements are also important for understanding overall sea-level rise due to global warming that scientists warn is a risk to the world’s coastlines and billions of people.
- Karen St. Germain, NASA’s Earth Science Division director said our Earth is a system of intricately connected dynamics between land, ocean, ice, atmosphere and also, of course, our human communities, and that system is changing,.
- She explained that 70 percent of the Earth’s surface is the ocean, the oceans play an enormous role in how the whole system changes.
By – Rajesh Tripathi
Links:-
https://www.firstpost.com/tech/science/nasa-esa-launch-sentinel-6-michael-freilich-satellite-to-monitor-the-oceans-9042931.html
https://www.nasa.gov/sentinel-6