Why In News?

NASA-funded scientists found that Teghaza 001, a rose-coloured meteorite discovered in the Sahara Desert in 2022, is one of the oldest pieces of Mars ever found on Earth.  

What Is Teghaza 001?

Discovery And Basic Features

  • Origin Of Name: The meteorite is named after the Teghaza salt plain in Mali, where it was found in 2022.  

  • Size And Colour: It is a rose-coloured rock weighing nearly 800 grams. 

  • Martian Identity: It is one of roughly 435 Martian meteorites identified on Earth. Scientists at the University of New Mexico first confirmed its Martian origin by analysing its oxygen isotopes.  

Rock Type

  • Igneous Rock: Teghaza 001 is a coarse-grained igneous rock, a plagioclase-rich gabbro. Its structure shows that it cooled slowly, probably underground.  

  • Unique Composition: Its texture and chemistry do not match any other known group of meteorites.  

  • Single Rock Type: Unlike some ancient Martian meteorites that are made of broken fragments, Teghaza 001 is a single, intact piece of ancient crust.  

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Age

  • Over 4.1 Billion Years: Uranium–lead dating of its zircon crystals gave an age of about 4.11 billion years, with an uncertainty of only about 13 million years.  

    •  Zircon traps uranium but excludes lead when it forms. As uranium decays into lead at a known rate, scientists can measure the ratio to date the rock precisely.   

  • Second Clock: A separate rubidium–strontium analysis gave a consistent but less precise age of about 4.24 billion years.  

  • Minimum Age: The researchers note that a heating event around 4.1 billion years ago may have reset these clocks, so the rock may be even older. 

Why Is Teghaza 001 Scientifically Significant?

Evidence Of Ancient Water

  • Water-Altered Rock: Chemical markers show that subsurface water altered the rock about 4.1 billion years ago.  

  • Active Water Cycle: This points to a more dynamic water cycle on early Mars than scientists previously understood. 

  • Window On Habitability: It is a direct witness to a time when Mars was wet and possibly suitable for life to emerge.  

Insights Into Mars' Evolution

  • Early Crust Formation: It shows how Mars' crust formed from cooling magma and was later changed by water.  

  • Atmospheric Loss: Its age coincides with the period when Mars began losing its early atmosphere to space.  

  • Guide For Exploration: Matching its chemistry to orbital data can help choose landing sites for future missions. 

What Are Meteoroids, Meteors And Meteorites?

 

Meteoroid

Meteor

Meteorite

Meaning

Small solid object orbiting the Sun

Streak of light seen when a meteoroid burns in the atmosphere

Meteoroid that survives the atmosphere and hits the ground

Location

Outer space

Inside a planet’s atmosphere

On the surface of a planet

Physical State

Solid rock or metal fragment

Glowing, burning body, often called a “shooting star”

Solid fragment that has survived entry

Size

From dust grains to about 1 metre

Visible light trail, usually from small meteoroids

Varies from small pebbles to large rocks

Visibility

Not visible from Earth

Seen as a bright flash or fireball in the night sky

Can be collected and studied in laboratories

Origin

Debris from asteroids, comets or planetary collisions

Created when a meteoroid enters the atmosphere at high speed

Fragments of asteroids, the Moon or Mars

Example

Debris from Comet Swift–Tuttle

Perseid meteor shower

Teghaza 001 (Martian meteorite)

 

 

Source: livemint

PRACTICE QUESTION

Q. Consider the following statements about Teghaza 001:

  1. It is a Martian meteorite discovered in the Sahara Desert in Mali.

  2. Its age was determined using zircon crystals.

  3. It shows no evidence of contact with liquid water.

Which of the statements given above is/are correct?

(a) 1 and 2 only

(b) 2 and 3 only

(c) 1 only

(d) 1, 2 and 3

Answer: (a)

Explanation:  

Statement 1 is correct: Teghaza 001 is a rare, rose-colored Martian meteorite discovered in 2022 in the Sahara Desert in Mali (named after the salt plain where it was located).

Statement 2 is correct: Researchers analyzed tiny zircon crystals (using uranium-lead dating alongside in-situ rubidium-strontium dating) to determine its crystallization age of at least 4.1 billion years, establishing it as one of the oldest known pieces of Mars ever found on Earth.

Statement 3 is incorrect: A key finding published in Science is that the meteorite preserves clear geochemical evidence of alteration by subsurface liquid water around 4.1 billion years ago, indicating a dynamic early Martian hydrological cycle.