Flowing water on mars
Q. Which of the following is/are true regarding Mars?
1) On Earth, inverted channels often occur in rainforest areas or areas with high rainfalls.
2) Lack of inverted channels on Mars suggests that Mars had water long back but was more of a dry area.- Published on 01 Sep 16a. Only 1
b. Only 2
c. Both 1 and 2
d. Neither 1 nor 2
ANSWER: Neither 1 nor 2
- Since the 1970s, scientists have identified valleys and channels on Mars which they think were carved out and eroded by rain and surface runoff, just like on Earth.
- Similar structures had not been seen on Arabia Terra until the team analysed high resolution imagery from NASA's Mars Reconnaissance Orbiter (MRO) spacecraft.
- While a few valleys were identified, the team found the existence of many systems of fossilised riverbeds which are visible as inverted channels spread across the Arabia Terra plain.
- The inverted channels are similar to those found elsewhere on Mars and Earth. They are made of sand and gravel deposited by a river and when the river becomes dry, the channels are left upstanding as the surrounding material erodes.
- On Earth, inverted channels often occur in dry, desert environments like Oman, Egypt, or Utah, where erosion rates are low - in most other environments, the channels are worn away before they can become inverted.
