Carbon dioxide in Earth's atmosphere if half of global-warming emissions are not absorbed. Credit: NASA/JPL/GSFC
By definition, pollution refers to any matter that is “out of place”. In other words, it is what happens when toxins, contaminants, and other harmful products are introduced into an environment, disrupting its normal patterns and functions. When it comes to our atmosphere, pollution refers to the introduction of chemicals, particulates, and biological matter that can be harmful to humans, plants and animals, and cause damage to the natural environment.
Whereas some causes of pollution are entirely natural – being the result of sudden changes in temperature, seasonal changes, or regular cycles – others are the result of human impact (i.e. anthropogenic, or man-made). More and more, the effects of air pollution on our planet, especially those that result from human activity, are of great concern to developers, planners and environmental organizations, given the long-term effect they can have.
Venus is often referred to as “Earth’s Twin” (or “sister planet”), and for good reason. Despite some rather glaring differences, not the least of which is their vastly different atmospheres, there are enough similarities between Earth and Venus that many scientists consider the two to be closely related. In short, they are believed to have been very similar early in their existence, but then evolved in different directions.
Earth and Venus are both terrestrial planets that are located within the Sun’s Habitable Zone (aka. “Goldilocks Zone”) and have similar sizes and compositions. Beyond that, however, they have little in common. Let’s go over all their characteristics, one by one, so we can in what ways they are different and what ways they are similar.
There may be a volcanic vent on the central peak of Tycho crater, according to an Indian research team. (Image: NASA Goddard/Arizona State University)
[/caption]
A team of researchers at India’s Physical Research Laboratory (PRL) claims it has found evidence of relatively recent volcanic activity on the Moon, using data from NASA’s Lunar Reconnaissance Orbiter and the Chadrayaan-1 spacecraft. According to the findings the central peak of Tycho crater contains features that are volcanic in origin, indicating that the Moon was geologically active during the crater’s formation 110 million years ago.
In an article by the Deccan Herald, a Bangalore-based publication, the PRL researchers claim that vents, lava channels and solidified flows of inner crustal material found within Tycho were made as recently as 100 million years ago — after the creation of the crater.
This could indicate that there was pre-existing volcanic activity within the Moon at the site of the Tycho impact, lending credence to the idea that the Moon was recently geologically active.
In addition, large boulders ranging in size from 33 meters to hundreds of yards across have been spotted on Tycho’s central peaks by LRO, including one 400-foot (120-meter) -wide specimen nestled atop the highest summit. How did such large boulders get there and what are they made of?
A 400-foot-wide boulder within the central peak of Tycho. (NASA/GSFC/LROC)
The researchers hint that they may also be volcanic in origin.
“A surprise findings revealed the presence of large boulders–about 100 meter in size –on top of the peak. Nobody knew how did they reach the top,” said Prakash Chauhan, a PRL scientist.
Without further studies it’s difficult to determine the exact origin and ages of these lunar formations. The team awaits future research by Chandrayaan-II, which will examine the Moon from orbit as well as land a rover onto the lunar surface. Chandrayaan-II is expected to launch in early 2014.
The PRL team’s findings were published in the April 10 issue of Current Science.
