ExoMars, Mars - Current Affairs Questions and Answers

ANSWER: Tonga

Explanation:
The world's newest island - formed during a volcanic eruption in the remote Pacific three years ago - may offer clues to how life potentially developed on Mars, NASA said on Dec 13, 2017.

The island of Hunga Tonga Hunga Ha'apai rose from the seabed about 65 km northwest of the Tongan capital Nuku'alofa in late 2014 or early 2015.

Scientists initially expected the island - created when vast quantities of rock and dense ash spewed from the earth's crust - to wash away within a few months.

But NASA said it had proved more resilient than expected, possibly because warm sea water combined with ash during the volcanic explosion to create a concrete-like substance known as "tuff".

While the island - which initially measured one km wide, two km long and about 100 metres high - has undergone significant erosion, it is now expected to last anywhere from six to 30 years.

Mars had many similar volcanic islands.

ANSWER: Aeolis Dorsa

Explanation:
Mars had a surface environment that supported liquid water about 3.5 billion years ago, according to a study of river deposits spread across the red planet.

A region of Mars named Aeolis Dorsa contains some of the most spectacular and densely packed river deposits seen on the planet, researchers said.

These deposits are observable with satellite images because they have undergone a process called “topographic inversion,” where the deposits filling once topographically low river channels have been exhumed in such a way that they now exist as ridges at the surface of the planet, they said.

With the use of high-resolution images and topographic data from cameras on orbiting satellites, researchers identified fluvial deposit stacking patterns and changes in sedimentation styles controlled by a migratory coastline.

They also developed a method to measure river paleo-transport direction for a subset of these ridges.

Together, these measurements demonstrate that the studied river deposits once filled incised valleys. On Earth, incised valleys are commonly cut and filled during falling and rising eustatic sea level, respectively.

Cardenas and colleagues conclude that similar falling and rising water levels in a large water body forced the formation of the paleo-valleys in their study area.

Cross-cutting relationships are observed at the valley-scale, indicating multiple episodes of water level fall and rise, each well over 50 metres, a similar scale to eustatic sea level changes on Earth, researchers said.

The conclusion that such large water level fluctuations and coastline movements were recorded by these river deposits suggests some long-term stability in the controlling, downstream water body, which would not be expected from catastrophic hydrologic events.

ANSWER: Both of the above

Explanation:
Mars is the basic target for scientists searching for life outside planet earth. Liquid water is the most important and critical prerequisite for life.

• But global scientists have found that the Red Planet is incredibly dry and has been so for millions of years
• More than 3 billion years ago, Mars was wet and habitable
• Latest research reaffirms just how dry the environment is currently
• Life is therefore not possible in Mars
• Scientists examined a cluster of meteorites at Meridiani Planum- just south of the equator and at a same latitude to Gale crater
• Researchers calculated the chemical weathering rate for Mars and how long it takes for rust to form from metallic iron present in the meteorites
• Chemical weathering process depends on the presence of water
• It takes 10 to 10,000 times longer on Mars to reach the same levels of rust formation on dries deserts on earth
• President day aridity has prevailed in the Red Planet for millions of years

ANSWER: China

Explanation:
Just after appointing an ambassador to India, China appointed the first ambassador to Mars to promote the country’s plan to send a spacecraft to Mars by the year 2020.

• Along with 10 other Chinese celebs, the ambassadors will popularise the space programme, encouraging interest in science and technology among the Chinese youth
• In April 2016, China launched the plan to send a rover to Mars to explore the red planet
• The aim is to launch it around 2020
• China is pursuing a lot into its space program, though India beat them with the mission to Mars in Sept 2014
• The United States has successfully landed two rovers on Mars while the former Soviet Union and the ESA have also sent missions to the arid planet
• China’s first attempt to send a satellite to Mars fell apart in 2011

ANSWER: Neither 1 nor 2

Explanation:

• 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.

ANSWER: Mars

Explanation:

• Mars had a warm and wet climate about four billion years ago and provided a more favourable environment for life, say scientists who have discovered fossilised riverbeds on an ancient region of the red planet.
• The study identified over 17,000 km of former river channels on a northern plain called Arabia Terra, providing further evidence of water once flowing on Mars.
• 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.

ANSWER: None of the above

Explanation:
Gullies on the surface of Mars were not carved out by flowing water. according to US space agency NASA.

• Gullies on the surface of Mars are similar to gullies found on the exterior parts of the Earth.
• Gullies found on the Earth are carved out by flowing water.
• There is no evidence of water being the cause of gullies found on the Martian surface
• According to NASA Mars Reconnaissance Orbiter, gullies on Mars appear to light up in different shades
• Martian gullies are a widespread and common feature on the planet as per observations by MRO High Resolution Imaging Science Experiment camera.
• These slopes appear in both hemispheres and occur on slopes that face towards the pole.

ANSWER: Water

Explanation:
The recurring slope lineae (Latin for line), dark streaks that change seasonally, on Martian slopes indicate presence of flowing water, as per a new study detailing thousands of such features in the red planet’s largest canyon system.

• Study investigated these warm season features in the Valles Marineris region near Mars equator.
• Some sites displayed seasonal flows including isolated peaks and canyon ridges, ground shapes that make it hard to explain the streaks resulting from underground water directly reaching the surface.
• It is unlikely that shallow ground ice would be present as a source for seasonal melting given the warm temperature in the equatorial canyons, according to researchers.
• Water pulled from the atmosphere by salts or mechanisms with no flowing water involved remain possible explanations for the features at these sites.
• These features are called recurring slope lines and since they were discovered in 2011, Martian RSL has become one of the hottest topics in planetary exploration, the strongest proof of liquid water on the Martian surface, even if it is transient.
• Occurrence of these slope lines in these canyons is much more widespread than previously recognised.
• They appear as dark lines extending downslope during the warm season, then fading away during the colder part of the year, then repeating the progression

ANSWER: Both b and c

Explanation:
Vegetables grown on soil in Mars have been found safe for human consumption according to Dutch scientists.

• In the greenhouses at Wageningen University in the Netherlands, scientists have worked on growing crops in Mars and Moon soil simultants since 2013
• The first experiment demonstrated that crops could grow on soil simulants with researchers mixing indelible parts of the 2013 plants into the simulant and succeeded to grow 10 different crops
• Heavy metals such as copper, lead and cadmium present in soils could contaminate the crops
• In case there are too high levels of heavy metals from the soil absorbed in edible plant parts, crops can become poisonous
• Wamelink indicated that radishes, peas, rye and tomatoes grown here can be eaten as no dangerous level of Copper, Zn, Fe or lead were found indicating the crops were safe to eat

ANSWER: Sol

Explanation:

• The term sol is used by planetary astronomers to refer to the duration of a solar day on Mars. A mean Martian solar day, or "sol", is 24 hours, 39 minutes, and 35.244 seconds.
• Mars has an axial tilt and a rotation period similar to those of Earth. Thus it experiences seasons of spring, summer, autumn and winter much like Earth, and its day is about the same length. Its year is almost twice as long as Earth's.