Late February was a very exciting time for astronomy. The National Aeronautics and Space Administration (NASA) announced to the world that it had discovered seven rocky, earth-sized planes orbiting a nearby cold, small star. The amazing news is that these seven planets could potentially have liquid water.
Is this a big deal? Short answer is yes. Three of these stars were found in what is known as the habitable zone around the star. It is known as the ‘Goldilocks zone’, where the temperature surrounding the star is not too hot, but not too cold – just right for liquid water to be present and therefore for life to flourish, given the right conditions.
This planetary system was named Trappist-1, after the Belgian-operated telescope in Chile discovered two of the seven planets in 2016. This led to NASA shifting its sights onto this planetary system by using the Spitzer space telescope. Along with the help of several ground-based telescopes, NASA discovered five more planets.
So how do astronomers detect such celestial objects which are so far away? The answer is that they have to observe the star to a very high degree over a very long period of time. It is not like pointing a telescope in the right patch of sky and physically seeing such planets.
What astronomers look for is a small tiny ‘dip’ in the radiance of the star. This dip would show that something has moved in front of the star similar to how light dims when one places a finger in front of a torch or during an eclipse.
Astronomers also look for a very slight ‘wobble’ in the star. This is because a planet would tug on the star just as much as the star pulls the planet towards it. This effect is similar to someone spinning on a ‘merry-go-round’.
By using these methods, astronomers are able to conclude to a very high degree the temperature and size of the star, how many planets are orbiting the star, their orbital period, as well as their sizes.
These planets are very close to one another so if we were to inhabit them, sunsets would be an astoundingly spectacular sight. So could we someday potentially inhabit these planets?
The answer is that we do not know yet. Inhabiting these planets would take a colossal effort which humanity does not yet have the means to do.
Getting to these planets would require a very long time and more research is required into human space flight. However, one thing is for certain, the quest for human knowledge and exploration will never cease to exist.
Did you know!
• Mars hosts Olympus Mons, the solar system’s largest volcano, standing 22km high. Two-and-a-half times as tall as Mount Everest (as measured from sea level), Olympus Mons is a large shield volcano dominating the red planet’s landscape. It was probably possible for such a massive feature to form on Mars but not on earth because of the lesser Martian gravity and also due to the probably higher lava flow rates on Mars in its initial stages after formation.
• Saturn’s largest moon, Titan, is the only moon in the solar system known to have an extensive atmosphere, which is even denser than earth’s atmosphere. Titan is the second largest moon in the entire solar system following Jupiter’s Ganymede, and is also larger than planet Mercury in diameter. Titan’s atmosphere is composed primarily of methane and nitrogen. Titan has surface lakes made of liquid methane and ethane, predominantly nearer to the Northern pole region, and these contribute to a methane cycle analogous to earth’s water cycle.
For more trivia see: www.um.edu.mt/think
Sound bites
• A storm of ice and fire led to snowball earth, dubbed as a ‘once in a billion year event’
Researchers have pinpointed the start of what’s known as the Sturtian snowball earth event to about 717 million years ago – give or take a few 100,000 years. At around that time, a huge volcanic event devastated an area from present day Alaska to Greenland, resulting in a global cooling event.
https://www.sciencedaily.com/releases/2017/03/170313160813.htm
• Record-setting star orbits dangerously close to its parent black hole
A white dwarf star nearly 15,000 light-years from earth apparently whips around its companion black hole once every 28 minutes, a new study suggests. That means the two objects are likely separated by just 2.5 earth-moon distances, making it the tightest such orbit ever observed around a black hole, study team members said.
http://www.space.com/36053-black-hole-closest-orbiting-star.html
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