NASA's Spitzer Space Telescope has spotted something great about 40 light-years (or about 229 trillion miles) from Earth. It's not a black hole, an exploding star, or an alien ship, but a system of seven temperate terrestrial planets revolving around a young, ultracool dwarf star known as TRAPPIST-1, named after The Transiting Planets and Planetesimals Small Telescope in Chile.
The latest discovery is unprecedented. All of the planets in the system could have water, with the chances of liquid water higher on the three planets within the habitable zone. Yes, not unlike in our own solar system with one planet in the Goldilocks Zone, TRAPPIST-1 has three worlds that might have the best conditions to support life.
TRAPPIST-1 is a red dwarf or M-dwarf star. Such stars outnumber and outlast yellow stars like our own sun.
How Spitzer Found The 7 Wonders Of TRAPPIST-1
The multimillion-dollar telescope in Chile was glued observing the young star over 21 days to measure the drop in light as the planets around it passed in front of it. It is far from being a simple process but in English, it involved watching out for tiny specks eclipsing the 500-million-year-old star to determine their mass, sizes, and possible atmospheric properties.
"The majority of stars are M-dwarfs, which are faint and small and not very luminous. So the majority of places where you would look for planets are around these cool, small stars. We are interested in the nearest stars, and the nearest stars are mostly M-dwarfs," said Martin Still, program scientist at NASA headquarters in Washington.
TRAPPIST-1 is about the size of Jupiter with the planets around it roughly similar to Earth's size and mass.
Below is a video by NASA's Jet Propulsion Laboratory and California Institute of Technology that provides an overview of how the planets were discovered:
What We Know About The 7 Exoplanets Of TRAPPIST-1
Revolving around TRAPPIST 1 are planets simply named as TRAPPIST-1 b, c, d, e, f, g and h.
Using the data obtained by Spitzer, scientists determined that the planets are likely to be rocky. Further studies are needed to determine if they could have liquid water or other secrets. The outermost planet's mass has not been determined and it might be an icy world.
The planets might also be tidally locked to TRAPPIST-1. This means that one side is always facing the star. Having a perpetual day one one side and perpetual night on the other has big implications on what the weather could be like on such planets.
Below is an artist's concept of how the planets might look like and a tabulation of their distances from TRAPPIST-1, radii, masses, and orbital periods as compared to Earth.
In case you're wondering what it will be like on the surface of one these alien worlds, check out the NASA VR that puts us on the surface of TRAPPIST-1d. Enjoy the 360-degree view:
Is There Life On TRAPPIST-1 Planets?
With such interesting findings come the usual questions. Are there life forms on TRAPPIST-1? Have we made contact with aliens? Can we someday move and live on these planets?
Whether there is life or not will remain a big question for a long time. There will be experts who will say a straight no while there will be those who will say perhaps.
"We've come up with these theoretical reasons why such a planet might struggle to be habitable. Then we look at those theoretical concerns with a little bit more detail, and find out it's not that big of a concern. Then some other theoretical concern crops up," said NASA research space scientist Shawn Domagal-Goldman.
TRAPPIST-1 is a very young star compared to our sun. Like other young stars, it is in its tantrum stage where it blasts nearby planets with a great amount of radiation and lethal flares.
Some think that life might exist and adapt is such harsh environments.
"Maybe the atmosphere can recover, and it's just fine. You have regular events, but life is used to this. It just deals with it. We certainly see life on Earth capable of hibernating for very extended periods of time. We see that life goes into a state where it shuts down, sometimes for years or decades. So I think we shouldn't, probably, rule it out, but we should put a lot of effort into studying whether this is a place where we think life could thrive," said senior scientist Tom Barclay of the NASA Ames Research Center in California.
Follow-up studies are planned using Spitzer, Kepler and Hubble. A more sensitive telescope, the James Webb Space Telescope, that will be operation starting 2018 will also be tapped. In combination, these equipment will help scientists get to know the planets of TRAPPIST-1 more and determine if they are really habitable.
The findings of scientists about TRAPPIST-1 appear in the journal Nature.
