Super Earth

Planet KOI-172.02 - Super Earth

KOI-172.02, which stands for Kepler Object of Interest, is a super Earth-size planet, meaning it has a radius 1.5-2 times the size of the Earth. While that may seem insignificant, it means that its mass is much more than that of the Earth, resulting in different properties such as a thicker gaseous atmosphere. It has been described as the most similar to our home planet yet.

The Kepler Mission, launched by NASA in March 2009, was specifically designed to survey a portion in our region of the Milky Way Galaxy to discover Earth-sized planets near the habitable zone, and to determine realistically how many of the billions of stars in our galaxy have such planets. The habitable zone is the region around a star where water might exist on the surface of a planet which provide favorable conditions for life.

The mission is designed to detect orbiting planets as they pass in front of their stars, causing a small decrease in the star’s brightness.

The Kepler Spacecraft and photometer, used to observe the stars, orbits the sun each year trailing behind the Earth. This spacecraft has found over 2,500 planets.

Kepler found planets by looking at just one large region of the Milky Way in the constellations Lyra and Cygnus. This region of space was picked due to certain limiting constraints; an environment rich in stars as well as one that can be continuously viewed and monitored throughout the mission “without obstruction of the Sun to the regions at any point of the spacecraft’s orbit”, say Dr. Howell, Deputy Project Scientist of the Kepler Mission at Ames.

Over the course of the mission, the Kepler spacecraft measures the variations in brightness, using the photometer, of 150.000 stars every 30 minutes, searching for tiny dips in the light output that occurs whenever a potential planet passes or “transits” in front of its star. Depending on the planet’s orbit and the type of star it orbits, this effect can last anywhere between an hour to about half a day.

Transits are only seen when a star’s planetary system is perfectly aligned with our line of sight, so if all the orbits are randomly distributed, as it should be, then Kepler – even if every star had a planet – would only see 1% of those stars having transits.

This is called “transit method” and is Kepler’s principal method in finding planets.

Regardless, the data received from the spacecraft is extensive in its own merit. Dozens of thousands of transit-like signals were analyzed and potential new planets were identified. Since not all variations in brightness necessarily represent a transit of a potential planet, there exist false positives. For example, there exist stars much like our Sun which can vary in brightness themselves. Such temporary phenomenon include “Sunspots” which create visible dark spots caused by intense magnetic activity. For that reason, the discovery of a planet is confirmed by observing a minimum of three transits.

Why three transits constitute a candidate planet? According to Dr. Alan Gould, co-investigator of the Kepler mission, the need for three transits explains as follows: Three transits are required for planet discovery by the transit method mainly because that is the minimum to assure that there is in fact a planet. One transit gives only the barest indication that a planet exists and an extremely rough idea at best of what the period of the planet might be. Two transits would pinpoint the period of the planet pretty pretty precisely, by virtue of the time between transits and allow accurate prediction of when the next transit is expected to occur. Actual observation of the third transit confirms the prediction and hence helps confirm the planet discovery”.

This would mean planets that are Earth-like and orbit around a star like our sun (every year) would take at least 3 years to get the three transits needed to be confirmed by Kepler to be a candidate planet. Once the planet candidate has been observed, it is then given the designation of KOI – Kepler Object of Interest). In terms of this new Super-Earth candidate KOI-172.02, it was the 172nd candidate in their running list of candidates to see if it really is a planet and has the right kind of star.

For the KOI-172.02 in particular, the 4 transit signals acquired by Kepler indicate that the planet orbits its star around every 243 days. We also know a lot about the star which KOI-172.02 orbits, which is very similar to our sum, but slightly smaller and colder.

The nominal mission of Kepler was 3.5 years, ending October 2012. Then it was in what NASA calls the extended mission. The next couple of years, Kepler started providing many more planets around stars like the sun that are much more like the Earth.

We have begun to contemplate our origins. Our loyalties are to the species and the planet. We speak for Earth. Image : © Megan Jorgensen.

Another Space-Time

Another Space-Time? - Pulsars

Ticking and blinking like a cosmic metronome, pulsars keep far better time than the most accurate ordinary clock, and anyone can see the beam of this cosmic lighthouse flash once each rotation of any planet (astronomers wonder how the sky would look from the surface of a planet rotating around a pulsar).

Long-term timing or the radio pulse rate of some pulsars suggests that these objects may have one or more small planetary companions. It is conceivable thus that a planet could survive the evolution of a star into a pulsar. Or a pulsar may have captured a planet at a later time.

If you could somehow survive the gravitational tides and radiation flux trying to land on a pulsar, it is just possible that you might emerge in another part of space-time – somewhere else in space, somewhen else in time. Might gravity tunnels provide a kind of interstellar or intergalactic subway, permitting us to travel to inaccessible places much more rapidly than we could in the ordinary way? Can pulsars serve as time machines, carrying us to the remote past or the distant future? The fact that such ideas are being discussed even semi-seriously shows how surreal the universe may be.

Such worm holes in space, a little like those in an apple, have been suggested by physicists and astronomers, although these phenomena have by no means been proved to exist.

May be, it’s for better, because we must be the most backward technical society in the Galaxy. Any society still more backward would not have radio astronomy at all. If the doleful experiences of cultural conflict on Earth were the galactic standard, it seems we would already have been destroyed, perhaps with some passing admiration expressed for Shakespeare, Bach and Vermeer.

But this has not happened. Perhaps alien intentions are uncompromisingly benign. Or might it be, despite all the pretensions about UFOs and ancient astronauts, that our civilization has not yet been discovered?

On one hand, if even a small fraction of technical civilizations learn to live with themselves and with weapons of mass destruction, there should now be an enormous number of advanced civilizations in the Galaxy. We already have slow interstellar flight, and think fast interstellar flight a possible goal for the human species. On the other hand, there is no credible evidence for the Earth being visited, now or ever. Is this not a contradiction? Pulsars, what role do they play in this? Will we ever know the answer?

Why are they not here, on Earth? May another space-time dimension play a role in this enigma? Image: © Megan Jorgensen.

The Function of Consciousness

The Function of Consciousness: Integrating the Two Worlds

How, without consciousness, would you know how you feel& That is the function consciousness. It is not only intrinsically introspective, it is also evaluative. It imparts value. It tells us whether something is “good” or “bad”; and it does that by making things feel good or bad (or somewhere in between). That is what consciousness, feeling, is for. (And that is why psychiatrists are interested in modifying the chemical outputs of these core brainstem nuclei.)

The evaluative function of our conscious “state” has its roots in the visceral monitoring structures of the core brain. This function of consciousness is therefore intrinsically biological. Its evolutionary survival vale is obvious: How long would we survive if we did not have a way of monitoring the delicate economy of the internal milieu of our bodies? The organ systems of our bodies can only function effectively within a very narrow range of set-points – with respect to temperature, blood-sugar level, and so forth. The most basic function of consciousness, then, is to monitor the state of these homeostatic systems and to report whether they are “contented” or not.

But bodily self-monitoring is only the most basic function consciousness. All our vital inner needs can only be met in the external world. The inner state of consciousness (which tells us, above all, what our current needs are) therefore has to be brought into connection with the current state of the world around us. Although, as we have seen, it is not necessary to be conscious of the external environment in order to perceive it, it is nevertheless useful. It is useful to able to say things like, “I feel like this (hungry), so I want to eat that thing over there,” or, “I feel like this (upset), because thing over there bit me.” In this way, consciousness – that is, value – is imparted to objects, and objects come to be known as “good” or “bad”. Consciousness is not only what you feel, it is what you feel about something.

The similarity between Freud's model and Damasio's is very striking. Photo by Elena.

Thus, even if the evolutionary “dawn of consciousness” was purely introspective, in a rudimentary biological sense, it probably quickly generalized, and our external perceptual modalities, too, became imbued with feeling (with consciousness). In this way, our external perception was transformed from being a set of (unconscious) information-processing channels into being the generator of the rich texture of perceptual qualities (conscious sights, sounds, smells, etc.) that we are now able to experience. This is consistent with the anatomical fact that the output of the core brain nuclei in question is broadcast very widely to the forebrain, and with the psychological fat that such “bottom-up” activation is necessary before higher cortical processes can become conscious.

Damasio therefore concluded that consciousness consists of more than mere awareness of our inner states; rather, it consists of fluctuating couplings of the current state of the object world. Each unit of consciousness forges a link between the self and objects. These momentary “units” of conscious time are probably generated by the rhythmical oscillations (the 40-hertz oscillations that characterize visual awareness). The oscillations are generated by pulses of activation of cortex, emanating from deep “reticulate” thalamic nuclei, thereby coupling the two varieties (or sources) of consciousness with one another many times per second. This is how we generate “the feeling of what happens” that provided the title of Damasio's book. Consciousness thus consists of feelings (evaluations) projected onto what is happening around us. Or, to put it the other way round, consciousness consists of awareness of what is happening around us, grounded in a background medium of self-awareness. Note especially that this explanation of consciousness solves both the binding problem and the homuncular problem. The various “channels” of consciousness are bound together by the grounding “state” of consciousness, which is itself the homunculus; the little person in your head is literally a projection of your bodily self.

Damasio calls this coupling mechanism “core consciousness.” Some further complications of consciousness exist.

There are many points of contact between Damasio's neuroscientific theory and those of other psychoanalytic theorists. Photo by Elena.

Limits of Knowledge

The Limits of Our Knowledge about Our Brain

Blindsight

The term blindsight (Weiskrantz, 1986) is applied to patients with damage to the visual cortex of the occipital lobes – the primary visual cortex – which is where most of the nerve fibers from the retinae terminate. Such patients suffer from “cortical blindness”; they are blind because the part of the cortex that generates visual consciousness is no longer working. Blindness, then, means a lack of visual awareness. Thus, if you were to hold an object before these patients' eyes and ask them what they see, they would respond with the obvious: “I don't see anything; I'm blind.” But when they respond in this way, they are actually mistaken. They are erroneously equating “seeing” with “seeing consciously.” The distinction between vision and conscious vision is demonstrated when you ask these same patients to make a “forced choice” between various options (in other words, you encourage them to guess). The results of such experiments reveal that they guess correctly at a level well above chance, which demonstrates that these patients are seeing – are processing visual information – without realizing it (see Weiskrantz, 1986). They are seeing unconsciously. This occurs because some visual information is projected from the retina onto other parts of the cortex (intact in these patients) that do not generate visual consciousness but are, nevertheless, equipped to process the visual information they receive. In other words, these patients – as far as visual information is concerned – act like the “zombies”. Their brains compute visually, but they do not possess visual consciousness.

Implicit Memory

The same thing occurs with respect to other cognitive faculties. It is not all that rare for neurological patients to lose the ability to lay down new memories. This condition is called amnesia. These patients remember (recall consciously) nothing that happens to them after the onset of their brain disease or injury. If you were to read a list of words to such patients, after a few minutes they would not only forget the words, they would even forget the fact that you read them the list. However, as with cases of cortical blindness, such patients can be encouraged to “guess,” using the forced-choice paradigm. When they do so, they “randomly” select of generate words that were on the original list, at a very much higher rate than chance. So, just as we can see unconsciously, we can also remember unconsciously. The technical term for this unconscious type of remembering is implicit memory (conscious remembering is explicit memory).

What is the self in neurobiological terms? Photo by Elena.

Split-Brain Studies

In so-called split-brain patients, to treat otherwise intractable epilepsy the corpus callosum has been severed, thus separating the left (language-dominant) hemisphere of the brain from the right

By briefly flashing an image on a screen to such patients, it is possible to provide the right hemisphere with information that the left hemisphere cannot access. On this basis, it is possible to influence the patient's behavior without him or her being consciously aware of it. In one of Nobel Prize-winning neuroscientist Roger Sperry's famous cases, pornographic pictures were projected and giggled. When Sperry asked her why she why she was embarrassed, she was unable to account for it. This case (described in Galin, 1974, p.573) demonstrates that an entire cerebral hemisphere can process information “unconsciously.”

The case also reveals something else that is of crucial importance for understanding consciousness. The visual cortex was completely intact in Sperry's patient. This means that the pornographic pictures were perceived by the visual-consciousness generating part of her right hemisphere. Why, then, did she appear not to know what she saw? The answer to this question provides a good illustration of the “functional systems” concept. Although it is true that the primary visual cortex (in either hemisphere) is capable of generation simple visual consciousness, it does not do so in isolation. For someone to reflect consciously on visual experiences, he or she has to recode the visual experiences into words. This capacity is lost when the left (verbal) hemisphere is disconnected from the original visual experience. This shows that a distinction needs to be drawn between two levels or types of consciousness: Simple awareness and reflexive awareness. It also shows that the function of reflexive awareness is intimately connected with the left cerebral hemisphere and therefore with word (or, rather, “inner speech”).

The fact that an entire hemisphere (about half of the forebrain) can, in a sense, function unconsciously raises intriguing questions.

Neuropsychology aims to be entirely objective, and its great power, its advances, com from just this. Illustration by Elena.

The Brain and the Inner World, Introduction to Basic Concepts. Mark Solms, Oliver Turnbull.

Is Mental Life Conscious?

How Much of Mental Life Is Conscious?

There are various ways of addressing the question of how much of mental life is conscious, each of which leads to slightly different answers. What they all reveal, however, is that consciousness is a very limited part of the mind. For example, if the extent of consciousness is equated with the amount of information that we can “hold in mind” at any one point in time, then readers might be surprised to learn that consciousness is restricted to only seven units of information.

It is no accident that most telephone numbers are roughly seven digits long. Digit span (the capacity to repeat a string of random digits) is a standard clinical test of as aspect of working-memory capacity. (“Working-memory: is synonymous with the ability to consciously “hold things in mind:). If a patient cannot retain roughly seven digits, his or her audiverbal working memory (audioverbal consciousness) information (or “location” information) in mind in a similar way, but this aspect of consciousness is even more restricted: most people can hold only some four units of visuo-spatial information in mind at a time. (This capacity is usually tested by tapping a series of blocks scattered before the patient and asking him or her to hold the sequence of taps in mind.) Considering how many thousands of pieces of information we are processing all the time, this way of measuring the capacity of consciousness reveals that it is very limited indeed. The vast bulk of the information we constantly need to process must be processed in the unconscious part of the mind.

Another way of estimating the “size” of consciousness is to measure the extent of its influence on our behavior. What proportion of our actions is consciously determined? In a review of the scientific evidence pertaining to this question (and related masters). Bargh and Chartrand (1999) concluded that 95% of our actions are unconsciously determined. This way of measuring consciousness therefore suggests that it accounts for only 5% of behavior.

So, regardless of how they measure it, mainstream cognitive scientists today agree with Freud on this point: consciousness is attached to only a very small part of our mental life. Where then, is this consciousness generated in the brain? And how does it become attached to mental processes? And why?

The Brain and the Inner World, Introduction to Basic Concepts. Mark Solms, Oliver Turnbull.

What, in neurological terms, might psychotherapists be doing when they treat a disordered “self”?