<u>RESEARCH ON PROXIMA CENTAURI:</u>
- Robert Innes discovered proxima centauri which is closest to the Sun in 1915 and it is believed to be 4.85 billion years old.
- Innes used a blink comparator though later he was in competition with another scientist named, Voute who provided theoretical values pertaining to the star more accurately than Innes.
- The recent findings found a planet which is located close to the Proxima Centauri making it the closest planet to our Solar System.
Answer: D. It can melt to a depth of a few meters in summer, then refreeze in winter.
Explanation:
Permafrost is ground which remains frozen for two or more years. Permafrost consists of soil, rock and sand fused together by ice. Mostly found in areas in high altitude, the Arctic, Antarctica, it is common in periglacial environments where temperatures are below freezing
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The topmost layer of permafrost can melt in summer and refreeze in winter. This thawing and refreezing produces a ground pattern called columnar joints similar to the one formed when molten lava cools.
Antarctica and Greenland provide examples of polar climates.
Happy Studying! ^-^
The inflation theory is your answer!