Terence Park's Blog - Posts Tagged "exoplanets"
Life out there: Trappist-1 exoplanets
The recent exoplanet announcement for Trappist-1 has received decent press. The Guardian reports Exoplanet discovery: seven Earth-sized planets found orbiting nearby star and in The Daily Telegraph, Sir Martin Rees, Astronomer Royal heralds this discovery with These new worlds are just the start. There are many more life-supporting planets out there waiting to be discovered. In brief what they are saying is that this is significant because there are many more Trappist-1 types of star than Sol types of star. Trappist-1 is Class M, a dwarf star; dwarf stars make up ¾ of all stars. They aren't as luminous so it's tough to work out what their systems are like; that's why this info is a snifter of (potentially) great things. Sol is of course Class G - 1 in 13 stars are like our Sun. These exoplanets have short years - in this case they range from a 1½ day year to a 20+ day year. From what we can tell they don't have moons but then again, the other planets are so close they will loom bigger in the sky than the Moon does to us. But no days, or months, just short years and a weird, planet filled sky.
What we know also places caveats on the discovery.
• Orbital speed is measured in days which implies a tidal lock - ie no rotation so no day or night, thus night side will lose heat and day side will be a heat sink, leaving only the borders habitable. See Zelazny's Jack of Shadows for a science fantasy depiction of such a world.
• Proximity of the star means 'weather phenomena' such as tectonic activity, radiation emissions and magnetic field, are much less attenuated by distance - the full planetary system is 10 times closer than the Earth is to Sol, noting that Trappist-1 is considered to be rich in metals.
• Proximity of other planets raises the question of orbital resonance - they pass closer to each other than the moon to the Earth.
• Sir Martin Rees mentions Tectonic in the context of evolution. There's another consideration: the Earth's molten core means a prodigious complement to the heat cycle of the Earth¹.
• The Moon - a Moon. Life here, particularly our form of life is closely dependent on the Moon, whether it's a romantic atmosphere, tides or regulating fertility.
• Taking this a step further, life here is attuned to the diurnal cycle, the lunar cycle and the orbital cycle - day, month, year. We've no idea what breaking these dependencies will do... we might say, heroically, 'it won't do nuthin'. :-)
• Panspermia ( a common source for life somewhere out there) deserves an honorary mention. We know that meteors have traces of organic compounds; if here then pretty much everywhere. Leaving aside the questions of source, age and prevalence; it's not a question of is there life out there? but where?
This helps build a picture of what is about us. The first waves of humanity out of Africa, doubtless took a keen interest in the world about them. Know the land, know the threats, know your enemies. We aren't able to get out into space yet but we can build up mental maps of where it might be useful to go. Of course that assumes nothing inimical.
More interesting (and more deadly for us) would be signs of advanced life. The language is SciFi but there are serious issues to be thought through. The fact that there's been no welcome committee to our dabblings in space up to this point, hopefully means just that. Not welcome. It is my hope that we remain unnoticed while we learn more; I can think of many bad things that would flow from being noticed and given our track record in planetary stewardship 'not welcome' is the best we could hope for.
¹ This facet has considerable significance for terraforming as a preliminary to colonising other planets. In my novel, The Tau Device, terraforming is forbidden, i.e. we are forbidden from making planets suitable for human habitation, this is an explicit precondition for humans to be granted access to space travel technology. The alien equivalent of terraforming, planetary seeding, won’t result in earth-like planets; alien biologies are different. The Tau Device works to a bigger picture, for example, Planetary Seeding is part of a larger process that begins with a Planet Survey.
We build a cosmology from fragmentary information. Discoveries of this kind help illuminate the quest for knowledge and are often an inspiration to SF writers. There is a cross fertilisation of ideas between the genre and the science and I take Robert Heinlein's view: writers ought to be acquainted with the science. First contact issues would have a significant impact on us as a species and are well worth exploring. They feature strongly in two of my books:
• The Tau Device: Humanity is a junior species in space... this shows I have a soft spot for the underdog.
• A Guide to First Contact: We've been contacted by aliens. They're not remotely interested in what we have to offer but the fact that we're not alone is tearing us apart... and the apocalypse has kicked off: delving into how humanity is programmed (the title is a play on words).
What we know also places caveats on the discovery.
• Orbital speed is measured in days which implies a tidal lock - ie no rotation so no day or night, thus night side will lose heat and day side will be a heat sink, leaving only the borders habitable. See Zelazny's Jack of Shadows for a science fantasy depiction of such a world.
• Proximity of the star means 'weather phenomena' such as tectonic activity, radiation emissions and magnetic field, are much less attenuated by distance - the full planetary system is 10 times closer than the Earth is to Sol, noting that Trappist-1 is considered to be rich in metals.
• Proximity of other planets raises the question of orbital resonance - they pass closer to each other than the moon to the Earth.
• Sir Martin Rees mentions Tectonic in the context of evolution. There's another consideration: the Earth's molten core means a prodigious complement to the heat cycle of the Earth¹.
• The Moon - a Moon. Life here, particularly our form of life is closely dependent on the Moon, whether it's a romantic atmosphere, tides or regulating fertility.
• Taking this a step further, life here is attuned to the diurnal cycle, the lunar cycle and the orbital cycle - day, month, year. We've no idea what breaking these dependencies will do... we might say, heroically, 'it won't do nuthin'. :-)
• Panspermia ( a common source for life somewhere out there) deserves an honorary mention. We know that meteors have traces of organic compounds; if here then pretty much everywhere. Leaving aside the questions of source, age and prevalence; it's not a question of is there life out there? but where?
This helps build a picture of what is about us. The first waves of humanity out of Africa, doubtless took a keen interest in the world about them. Know the land, know the threats, know your enemies. We aren't able to get out into space yet but we can build up mental maps of where it might be useful to go. Of course that assumes nothing inimical.
More interesting (and more deadly for us) would be signs of advanced life. The language is SciFi but there are serious issues to be thought through. The fact that there's been no welcome committee to our dabblings in space up to this point, hopefully means just that. Not welcome. It is my hope that we remain unnoticed while we learn more; I can think of many bad things that would flow from being noticed and given our track record in planetary stewardship 'not welcome' is the best we could hope for.
¹ This facet has considerable significance for terraforming as a preliminary to colonising other planets. In my novel, The Tau Device, terraforming is forbidden, i.e. we are forbidden from making planets suitable for human habitation, this is an explicit precondition for humans to be granted access to space travel technology. The alien equivalent of terraforming, planetary seeding, won’t result in earth-like planets; alien biologies are different. The Tau Device works to a bigger picture, for example, Planetary Seeding is part of a larger process that begins with a Planet Survey.
We build a cosmology from fragmentary information. Discoveries of this kind help illuminate the quest for knowledge and are often an inspiration to SF writers. There is a cross fertilisation of ideas between the genre and the science and I take Robert Heinlein's view: writers ought to be acquainted with the science. First contact issues would have a significant impact on us as a species and are well worth exploring. They feature strongly in two of my books:
• The Tau Device: Humanity is a junior species in space... this shows I have a soft spot for the underdog.
• A Guide to First Contact: We've been contacted by aliens. They're not remotely interested in what we have to offer but the fact that we're not alone is tearing us apart... and the apocalypse has kicked off: delving into how humanity is programmed (the title is a play on words).
