For all of human history we have been exploring the unexplored, from discovering new lands to the seas and to the skies. Now as we have conquered those challenges we are presented with our next goal, space. In it is filled with billions upon billions of galaxies, stars and even other solar systems. Planets that roam their parent star outside of our own system are called extrasolar planets or exoplanets for short. Here are 5 of my favorite exoplanets discovered up to date.
1. First siting – Pulsar PSR B1257+12A
Located 1000 light years away from our sun PSR B1257+12 became wasthe first confirmed detection of a pulsar with several large masses orbiting it. It was later confirmed in 2007 that 3 exoplanets (with masses of 4.3x, 3.9x, and 0.02x the mass of our earth) orbit the pulsar.
Fun Fact #1: Pulsars are rapidly rotating neutron stars.
2. Two incredibly close orbits – star Kepler-36a
Located 1,200 light years away, the star system Kepler-36 and 2 of its orbiting planets have been striking a craze recently, why you may ask? Because these 2 planets have very dangerously close orbits, so much that the gravity from the 2 planets Kepler-36b and Kepler-36c would have significant tidal forces on each other (if either of them had any large bodies of water on them, like oceans or seas). Kepler-36b is a large terrestrial planet with 4.5x the mass of the earth also known as a super Earth. And Kepler-36c is a large Neptune like gas planet 8 times the mass of our planet. Every 97 days or so the 2 planets would synchronize with each other and will get as close as 1.9 million kilometers, or about 5 times the distance from the ground to the moon. Although 1.9 million kilometers may not sound anything short of a long way it is 20 time times the distance from our planet is Venus at 39 million kilometers away. But if all these numbers are too difficult to imagine (and I sure bit it will be especially because it is in the metric system). Here’s a photo-shopped picture of how the skies may look from the surface of rocky super Earth Kepler-36b. From the surface of Kepler-36b the other planet (Kepler-36c) would take up 3 or 4 times as much sky space as a full moon on Earth would.
Fun Fact #2: Super Earths can be classified as any rocky planet with a significantly higher mass than that of our earth. So the planet Kepler-36b has a mass of 4.5x that of our Earth, so it can be classified as a Super Earth; however Kepler-36c cannot be a super earth, although it is 8 times the mass of our earth, it is a gas planet.
3. Largest exoplant yet – Star TrES-4
The planet TrES-4b was discovered in 2006 and is currently known as the largest planet outside of our solar system to date. TrES-4b is70% larger than Jupiter, however, strangely enough it only contains 70% of the mass of Jupiter making it a very low density gas planet. In fact TrES-4b is just about as dense as the cork found on your champagne bottle.
Fun fact #3: Exoplanets are named from their parent stars in order of their discovery and not the distance from the central star, which can often lead to confusion. However the central star has its own name reserved as whatever name then lowercase letter ‘a’. So for example Kepler-36a or Kepler-36 is the star name, while Kepler-36b, c, d … and so on are left for the orbiting planets.
4. Triple Star System – HD 188753
Located approximately 150 light years (which is about 1.5 quadrillion kilometers) from the constellation Cygnus. With a central star mass of 1.06 solar masses (1 solar mass = the mass of our sun), along with a pair of smaller stars with a combined mass of just 1.63 solar masses. A Jupiter like gas planet has been detected in the triple system; it orbits its main star in a mere 3.5 earth days. So from the surface of this planet you'd seee not one, not two, but 3 stars rising and setting. 2 small suns and one large one.
Fun Fact #4: In the constellation Cygnus exists an earth like planet existing in the habitable zone, or as some like to call it, the Goldilocks Zone. An area where a planet is neither too far or too close to its host star, allowing a nice temperature fit for life. Earth resides in the middle of a goldilocks zone in our solar system. Kepler-22b was the first goldilocks planet discovered by the Kepler space telescope in 2009 and was later confirmed to exist in 2011.
5. Diamond planet – PSR J1716-1438b
This is another planet that orbits a pulsar which spins at 10,000 revolutions per minute or about 167 times per second. But what’s incredibly interesting about this planet is that because of its high density and gravity, it is possible that the exoplanet’s own gravity may have crushed the carbon within into crystalized diamonds, that's right diamonds. It exists about 4,000 light years (40 quadrillion kilometers) from the Earth in the constellation Serpens. Shown below is the system with the pulsar in the center with the exoplanet orbiting around it.
Last Fun Fact #5: 1 light year = about 10 trillion kilometers
If you liked this "top five exoplanets" then you may also like "Top Five Stellar Phenomena" found here: http://expertscolumn.com/content/final-frontier-space-top-five-stellar-phenomena