Our Holy Grail

There’s always that Quest, that insatiable quest to find the most important thing of all. In the field of Exoplanet Science, planet-hunters are actively pursuing to discover the first earth-like planet, or the first inhabited exoworld. Is that the holy grail in exoplanet science? Perhaps.

But in stories where the holy grail is mentioned within the plot, they often contain twists that leave the audience in awe of the unexpected. Such a twist is worth re-telling in this post because it is a monumental event in the history of Exoplanetology.

One night, after his talk on exoplanets at the American Museum of Natural History, the astrophysicist Ben Oppenheimer poignantly answered this question, "What is the Holy Grail in Exoplanet Science?"

“For me, the Holy Grail in Exoplanet Science is simply being part of it. It’s not making the best exoplanet discovery, or being in the news and all that; It’s simply being part of the collective efforts of the people around the Science of Exoplanets.”

I still remember that idea so clearly, despite the slight tipsiness from the booze of red wine and olives served at the SciCafe event. As I headed home that night, I couldn’t fathom how the common folk would ever be able to find planets at all. And I wondered how simple citizens could help well-trained planet-hunters.

For many months thereafter, I looked into different Citizen Science projects that show potential. I even wrote about the need to enable the common folk to contribute to the hunt for exoplanets, 'subtly' urging astronomy-oriented organizations to embark on such a project.

Then one day, I became excited about Zooniverse’s Milky Way Project, wishing that they make one for exoplanets, too. I asked the hive mind...almost pleading: When will Zooniverse make one for Exoplanets?

I was shocked a few days later. Along came Planet Hunters, the latest project by Zooniverse that enables citizens to find exoplanets!

Hear ye! Hear ye! The Holy Grail of Exoplanet Science is not an object. It’s not even a special exoplanet. Rather, it is the swarm of people--the community--embarking on a mission to find exoplanets. Ultimately, such undertaking will lead us to answer some of man’s greatest questions: Are there worlds like ours out there? Is there life on other worlds?

Planet Hunters is a Citizen Science project that allows volunteers to sieve through data taken by the NASA Kepler space mission. Participants search for possible transit events by looking at light curves and identifying dips in brightness that occurs when a planet passes in front of the star - with the goal of discovering a planet (hence the name "Planet Hunters").

The response to Planet Hunters was enormous. So much that in only a few weeks, there’s already a couple of exoplanet candidates flagged by several Citizen Planet Hunters (CPH). So far, I’ve not been so lucky of being among these sharp-eyed exoplanet hunters, but I am just happy contributing in the search for planets, no matter how small it is. I’ve tagged a few stars, and identified some dips from several light curves, and so far the experience is awesome. Perhaps it's a subjective experience, that the holy grail in exoplanet science could mean many things to different people. But one thing i know, is that this is my holy grail--our holy grail--for all those who take part in it, and drink from its cup.

Links:
The Holy Grail in Exoplanet Science
Data Mining Age in Exoplanet Science
Planet Hunters by Zooniverse

Exobiology, Astrobiology and Exoplanets

So I tried Google's Ngram viewer on Exobiology, Astrobiology and Exoplanet, and came up with the chart shown above. As an added perk, I overlayed the yearly count of exoplanet discoveries on the graph.

As you can see, the term Exobiology was more popular than Astrobiology back then. And the word "Exoplanet" never occurred in any books prior to the 80's. But it all changed when the first confirmed exoplanet was announced in 1992. It was then that the trend of the exoplanet began, and propelled a sudden surge of interest in Astrobiology.

As new exoplanet discoveries continued to pile up, so did the field of Astrobiology continue to grow, evident in the increasing usage of the term in published books. By 1997, a few years after the discovery of 51 Pegasi b, the word astrobiology overtook exobiology.

Suddenly, Astrobiology was hip. It became increasingly more popular overnight, as if riding on the wave of exoplanets.

But what happened with the word Exobiology? Why didn't it pick up as much as Astrobiology did? It's a curious historical note, and the answer could be anyone's guess. And I'll give it a try.

The term Exobiology was coined by a Nobel Prize-winning scientist named Joshua Lederberg. I do not know exactly when the word Astrobiology was adopted to replace Exobiology but all we know is that it specifically means the "study of life beyond the Earth". But since there's no known life beyond the Earth (yet!), people said it's a field with no subject matter. That may well be a plausible reason why the term didn't catch on, no matter how cool the prefix "exo" is.

And since the term Astrobiology already picked up the momentum, it also locked on as the bastion to the science of "Life elsewhere in the universe"--a phrase that makes it seem a wider field than by just saying "Life outside earth".

Now here are questions to entice the next generation. Will exobiology make a comeback? Do you think the word exoplanet will skyrocket in the next decade? And what about...ahem...Exoplanetology?

Only time will tell.

Exogasm

I woke up one day wondering what kind of "gasm" I would describe for that ecstatic feeling about exoplanets. I toyed around with "exogasm". And I liked the fun suggestions from the twitters. But never did I realize that on that same day (December 1) my mind would be blown by a kind of cerebral experience brought about by the prospect of new worlds. Lots of them!

Several "foreplay" news items came into view through my twitter stream. First was that news of the first time a super-earth's atmosphere was ever examined.

But nothing would prepare me for a gasm that is truly mind-blowing: The number of stars in universe were more numerous than previously thought--so much more that the total number of stars in the universe is likely three times bigger than realized!

The tidbits below says it all in one word: Exogasm!

"There are about 20 times more red dwarfs in elliptical galaxies than in the Milky Way. In addition to boosting the total number of stars in the universe, the discovery also increases the number of planets orbiting those stars, which in turn elevates the number of planets that might harbor life."

"There are possibly trillions of Earths orbiting these stars."

Links:
Latest Star Census Increases Number of Exoplanets
Atmosphere Around Super-earth analysed for the first time

Exoplanet is the new Planet

I try to stay away from the debate about Pluto. My issue is not about Pluto. It's about the Planet. One can mock Pluto a thousand times over, and the best (or worst) it could do is annoy people. Sometimes it does get to me, so i have to remind myself that I am more concerned about the concept of the planet, and the idea it represents, and the ideal it imparts to the human psyche.

Let me begin by saying that I think I am falling in love with planets. I don’t know how, but during the course of following the saga of exoplanets it must have been inevitable (after all, the ‘exoplanet’ bears the name of ‘planet’).

With new discoveries that pour in almost daily about planets in other star systems, Exoplanets are a constant source of amazement. They continue to remind me that I can never know enough, that this fascinating universe is an endless source of wonder.

But...something keeps getting in the way. Something mind-numbing creeps in when I read something about what a ‘planet’ is defined to be. It has bothered me so much that I had to use “worlds” as an alternative keyword to hook me back in wonder about these spherical objects in space.

Why? What happened with the term “planet”? What happened with the magical and mythical concept that the Greeks once started with, saying that these mysterious points of light are ‘wanderers’?

The problem began when mankind started to *define* the Planet. We relentlessly squished the concept of a planet with words so that it could fit within our tiny skulls.

I looked into the two sides of the debate, learning as much as I can to understand, but the mandated definition of the Planet really does not appeal to me. In the spirit of freethinking, I humbly decline to subscribe in the 'official' definition of the planet.

Why? What have humans done to the concept of the planet?

There is nothing inherently wrong with classifying things, and certainly nothing wrong with identifying the boundaries in order to characterize objects, but I think we had the wrong attitude when we made up the criteria for planets.

And that is the sad thing about it. Instead of trying to widen the concept of the Planet, we tried to limit it. The kind of thinking that is promoted by the current definition of the planet is a divisive mode of mentality. You see, in our world, much strife is borne out of a discriminating mindset--a way of thinking that focuses on the differences and not on the similarites.

"The major problems in the world are the result of the difference between how nature works and the way people think." ~Gregory Bateson

Today, dwarf planets are not considered planets at all, despite calling them 'dwarf planets'. Is it a matter of linguistic fallacy that makes it all nonsensical? (Dwarf galaxies are galaxies, and dwarf stars are stars, but dwarf planets are not planets?)

Or is it just the mode of thinking? Why deny dwarf planets of being planets? Such judgement mirrors a way of thinking that is alienating and divisive.

It is certainly valid if you consider dwarf planets as a subset or variation of the wide scope of planets. This alternative method of classification exemplifies a way of thinking that respects differences and yet aims to see things as One.

You can choose a mindset that seeks to see all kinds of planets in a wholistic fashion, and delight in their diversity. Or you could choose a discriminating mentality, segregating a class of planet-worlds that don’t fit in your limited notion based on one star system alone--yours.

The Pluto debate is a clash of mentalities. And it has marred the concept of the planet. I hope that the next generation never inherits the discriminating mentality that is present in that conflict.

I rest my case in the lessons that exoplanets are teaching us. They continue to challenge our pre-defined notions of what a planet truly is. They continue to be a source of wonder, in the same way that the Ancient Greeks felt about their ‘wanderers’. In our modern era, only the Exoplanet can conjure that feeling of mystery and discovery ascribed to such mysterious objects.

For me, Exoplanet is the new Planet.

I wish we never end up defining the Exoplanet in the same way we did for the Planet, for I wish to keep the concept of the Exoplanet with awesomeness and wonder.

Exoplanetary Bow Shocks

Exoplanetary Bow Shock

We've heard of stellar bow shocks before. But I bet no one has heard of bow shocks of planets just yet! Exoplanetary Bow Shocks would be an amazing sight to see. I am surprised by the lack of pictures that I can find on the web on how it would look like. So I made one of my own.

Now here's an unusual trivia about exoplanetary bow shocks which caught my attention: Exoplanetary Bow Shocks can also appear from behind the planet! Astrophysicists call them "behind-shocks".

“Another case, is when the shock trails the planet. In the “behind-shock” case, the planet orbits the star beyond the Keplerian co-rotation radius, so that the coronal plasma lags behind the planetary motion. In order to develop a behind-shock, the planet must be in a prograde orbit.”

Now, of course I wanted to imagine how a bow shock would look like when viewed from the surface of the planet. A question brewed in my mind: Would an exoplanetary bow shock look like the Aurora? Yes. But you would not be around long enough to see much of it, for the bow shocks described in the paper are stellar plasma emanating from the star that interacts with the magnetic fields of both the planet and star itself. Imagine yourself being burnt to a crisp while watching a beautiful 'Aurora' show.

“The planetary magnetic field is believed to be responsible for shielding the planet against the erosion of the planetary atmosphere by the host star’s wind or the impact of energetic cosmic particles. Such effects could harm creation and development of life in the planet.
Furthermore, the presence of a planetary magnetic field may induce star-planet interactions, e.g., through reconnection between stellar and planetary magnetic field lines.”

But of course, planets farther away from the star would have a more gentler bow shock, and a milder shower of stellar material. I would assume different kinds of beauty and variety that one would see if one were to look up from the surface of an exoplanet with a faint bow shock. And it hit me! We have those here on earth! We know them as Aurora Borealis and Aurora Australis!

And that whole visual imagining is the whole reason why the arxiv paper inspired me to write a story, entitled “Worlds Hopper”. The ArXiV paper is rich with information. It contains lists and data tables of exoplanets which may possibly have bow shocks. Some of them are WASP-12b, OGLE-TR-56b, WASP-19b, SWEEPS-11,WASP-4b,WASP-18b, CoRoT-7b, CoRoT-14b, HAT-P-7b, OGLE-TR-132b, CoRoT-1b, TrES-3, and WASP-5b.

Well, these bow shocked exoplanets are quite a handful, eh? Go check out the paper and tell me what you think.

Links:
Prospects for Detection of Exoplanet Magnetic Fields Through Bow-Shock Observations During Transits
Transit Variability in Bow Shock-Hosting Exoplanets (PDF)
Short Story: Worlds Hopper

Other Platforms of Life

Mono Lake, where the arsenic-loving GFAJ-1 was found.

Life as we know it appears to have a common base. All of us, from the smallest amoeba, to the largest whale, share the same platform of life: Carbon.

And we think that life can only occur in one way, in one place and at one time in the history of the earth.

Today, all that is about to change.

NASA scientists have found a bacteria whose biochemical make-up is quite different from the carbon-based life that we know of.

A bacteria called GFAJ-1 has been found in Mono Lake that eats arsenic, and also incorporates arsenic in its DNA as replacement for phosphorus--one of the usual set of components of "CHNOPS" (carbon, hydrogen, nitrogen, oxygen, phosphorus and sulfur) that form the basis of all life on earth.

I’ve always believed that our form of life is the only possible configuration. And now there is direct scientific evidence that it is possible for life to occur in other platforms.

This finding is mindblowing. It gives a preview of a "shadow biosphere" that could exist on our planet, and may strengthen the idea that life may be rampant elsewhere in the universe. All the more that this fascinating discovery was announced a day after astronomers revealed that the number of stars is 3 times more numerous than previously known--which means that there are gazillions more of exoplanets exist!

If we just found a hint of “shadow life” on our very own planet, then one can imagine the richness of life originating on other conditions and other chemicals on other planets.

Links:
Arsenic-eating microbe may redefine chemistry of life
Arsenic-Eating Bacteria Opens New Possibilities

The Exoplanet Generation

Image credit: ESO

I asked my seven-year-old daughter, "What do you call a planet outside our solar sys..." I didn't even finish my question when she excitedly exclaimed, "EXOPLANET!!!"

I laughed. She smiled. And then I realized: I am talking to a child of the "Exoplanet Generation", the young ones that were born from 1992 and onwards. It's the year when the first discovered exoplanet (orbiting a pulsar called PSR B1257+12) was announced. From then onwards, the accelerating rate of discovery defined the pulse of the Exoplanet Generation.

These "ExoGen" kids will grow up in a world very different from our own. When I was seven, i had no idea about other worlds. But the children of the exoplanet generation will bask in the weekly or daily news about the new exoplanet discoveries. They will wake up hearing new discoveries about how other lifeforms in platforms other than carbon may be able to thrive, or how life is possible on planets and moons outside our solar system.

Perhaps, in their lifetime they will witness the discovery of exolife, or be the ones to make the discovery itself, of life on other worlds!

And so, ExoGen kids...Welcome to brave New Worlds!

Exogazing 51 Pegasi b

It's been a while since the last time I spotted stars with known exoplanets. So, I decided to sneak out last night, grabbing my binoculars and hurrying out to my back yard, droid in my pocket running the latest version of the Sky Map app.

The target: 51 Pegasi b (51 Peg b), around a faint star (magnitude 5.5) located just a little to the side of the line connecting Markab and Scheat, two of the four major stars making up the “Great Square” of Pegasus.

It was relatively easy spotting 51 Peg, thanks to the two guide stars--Sadalbari and Sadalpheretz--all three of them fit nicely within a 4.5 Deg FOV of my binoculars.

The circle denotes what I see through my binoculars with a  4.5 degree FOV 

When I tried to verify what I saw through my binoculars by consulting my starmap, I grabbed a quarter coin to draw a circle to denote my binocular’s FOV. To my surprise, the coin's circle fits nicely with the FOV of my binoculars!

The quarter coin matches my binocular's FOV of the night sky!

Discovering that a quarter coin is approximately 4.5 degrees on my starmap which closely matches what I see of the night sky through my binoculars, would allow me to exogaze a little bit faster next time. Yay!

Giordano Bruno, Imaginative Logic, and the Plurality of Worlds

I am gripped by a certain sense of nostalgia every time I read old books. There's something about those archaic sentences, or the fonts, which I imagine being printed by old, rusty movable types. Even more so, is that I am intrigued by the authors’ way of thinking in those early days when Science and Astronomy were in its infancy.

Thus, in the inquiry about other Worlds, what were the thinker's methods of thought in the olden days when there was no internet? How far can their ideas go when all they had were just the pure sight of Nature to power their brains?

Yesterday, I came across this book "Giordano Bruno and Renaissance Science", in which the author reevaluates Bruno's contribution to the scientific revolution. We all heard about that the guy before, that pesky hooded friar who got burned at the stake for his heretical views.

Now let’s take a peek at how Bruno came up with his Philosophy and way of thinking. In one instance, Bruno “wishes to prove that opaque bodies lying between the eye and luminous bodies can easily disappear from the field of vision: a point which he illustrates by holding a matchstick between his eyes and a lighted candle."

Albeit primitive, Bruno noted the same difficulty involved in exoplanet-hunting; that it's like trying to find a firefly across the backdrop of a searchlight, as modern-day astronomers would often say. Had Bruno written that the distant star's light would be dimmed in a measurable way by an orbiting planet passing across the viewer's line of sight, he would have hinted at one of the most successful methods in Exoplanet-hunting, the Transit Method.

In his time, such an insight is not bad. Apparently, Bruno used "Imaginative Logic" (in contrast to rational logic) as his thinking method to come up with his ideas, which were considered quite radical at that time. Nevertheless, Bruno stumbled onto something bigger, an idea so true and powerful that he was willing to give up his life for it.

Today with more than five hundred known worlds on other stars, we are basking in that idea now.

The Plurality of Worlds "...constitutes the essential premise for the new cosmology of Bruno, whose universe is filled with infinite worlds, most of which are invisible to the naked eye."


"In space there are countless constellations, suns and planets; we see only the suns because they give light; the planets remain invisible, for they are small and dark. There are also numberless earths circling around their suns, no worse and no less than this globe of ours. For no reasonable mind can assume that heavenly bodies that may be far more magnificent than ours would not bear upon them creatures similar or even superior to those upon our human earth."
~ Giordano Bruno, 1584


"All philosophy is based on two things only: curiosity and poor eyesight; if you had better eyesight you could see perfectly well whether or not these stars are solar systems, and if you were less curious you wouldn't care about knowing, which amounts to the same thing. the trouble is, we want to know more than what we can see."
~ Bernard le Bovier de Fontenelle, Conversations on the Plurality of the Worlds, 1686

Links:
Giordano Bruno and Renaissance Science

Exoplanet 500

I wrote this post to mark a milestone in Exoplanet Science. There are now over five hundred known exoplanets in our database.

It may not be such a big deal. Five Hundred is not much. Not until one considers the fact that gazillions of planets wander the galaxy. It means that cataloguing worlds is an infinite pursuit. Such task tickles the potential of the whole human race, and the human mind.

We have "Indy 500", and we have "Fortune 500", now why not have "Exoplanet 500"?

Yes, "Five Hundred" is fun to utter. And as I sing it out loud, I reflect upon the accomplishments of the Astronomers whose dedication continue to expand our view of the Cosmos.

Amazing how far we've gone as a curious species.

Now's a good time to pause and appreciate the contributions of the rest of the Scientists, Philosophers, Artists, Thinkers and Dreamers--not only those that are currently in our midst, but especially those who have gone before us. They are the Giants upon whose shoulders we are standing on to get a better view of our wondrous universe, enabling us to glimpse New Worlds.

"For I would walk 500 miles, and i will walk 500 more..."
~ The Proclaimers, I'm Gonna Be (500 Miles)

Tadalala! Tadalala...tadalalalalalaa...


Links:
Exoplanet Encyclopaedia

Intergalactic Planetary...Planetary Intergalactic...Another Dimension...Another Dimension...

I don't really listen much to rap music, but today I suddenly found this song playin' inside my head.

"Intergalactic Planetary...Planetary Intergalactic...Another Dimension...Another Dimension..."

So what's with the rapping and a-tapping, you ask? Well, we've just found a planet that's "Intergalactic". And rightly so. Because this planet named "HIP 13044 b" actually originated from another galaxy which was eventually swallowed up by our own Milky Way galaxy. Yes, it moved from one galaxy to another. And that makes it truly Intergalactic!

Yeah, yeah so what does the "another dimension...another dimension" got to do with it? Well, on this same day after the exogalactic exoplanet was announced, news came out of the possible proof of extra dimensions via the bending of light by black holes. Yup, another dimension...another dimension...

Now do you understand why the Beastie Boys are screaming in my head? "Intergalactic Planetary...Planetary Intergalactic...Another Dimension...Another Dimension..."

Links:
Planet from Another Galaxy Discovered (ESO)
Extragalactic Planet by PhysOrg
Extragalactic Exoplanet via SciAm
Proof of Another Dimension?

My First Foray into Data Visualization with Exoplanets

Einstein said, "If I can't picture it, I can't understand it." This statement proved itself to be true on my first foray into Data Visualization. And let me add that it was absolutely a fun experience being able to play around with all the data using the excellent tool provided by "Many Eyes" which was instrumental in helping to reveal insights that lay hidden within those rows and columns of numbers. And of course, it wouldn't be possible at all without the data! So I am thankful for the folks at exoplanets.org for providing the dataset.

Now I realized that, "If you can't explain it simply, you don't understand it well enough." Yes, Einstein also said that. And I think that is the final part of Data Visualization (which i presume overlaps with Data Journalism in some way, too). It was fun generating the visualizations, and analyzing them to find insights was challenging--but it is not complete without the ultimate goal of communicating what I have discovered.

Sure, the pictures speak for themselves (in more than a thousand words), but there is an added benefit in formulating a simple statement to convey the insight: it makes you learn the concept even more. Finally, being able to share that understanding completes the joy.

Let me warn you that I am not a scientist, so please bear with me as i briefly explain my own original findings from these pictures (and please correct me if i'm wrong). Also let me iterate that I'm not a designer or an artist, so the graphics presented in this post are no match compared to the aesthetics of David McCandless (Visual Miscellaneum), and the analytical prowess of Edward Tufte (Envisioning Information).

The conclusion(s) I've drawn from the visuals pretty much explains it concisely. The additional notes are supplementary.

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Fig. 1: Visual Magnitude vs Discovery Method (used to find the exoplanet)
Conclusion: The magnitude or brightness of host stars whose planets were discovered via Transit Method are generally dimmer than those stars whose planets were discovered via Radial Velocity (RV) Method. Here's another proof.
Analysis:
Transit Method works best on dimmer stars because it does not drown out its own planets in its glare as much as a bright star would. Radial Velocity (RV) method works best on brighter stars for better spectographic analysis.

Fig. 1: Visual Magnitude vs Discovery Method

Notes:The label delineating the two methods are not noticeable so i need to point out that the left section are those host stars with planets were discovered via RV method. The smaller section on the right with a noticeably darker shade are those stars with transiting planets.
The dimmer tint for high values of Visual Magnitude (V) fits well with the fact that stars with a higher value of magnitude (V) are actually dimmer than those with a lower value.
[Link to the interactive version at Many Eyes]

Fig. 2: Discovery Method vs. Exoplanet Names
Conclusion: Exoplanets discovered via RV method have more "generic" sounding names than those discovered via transit method.
Analysis:
Here's a nice tip on how to quickly guess whether an exoplanet was discovered via RV or transit method: If it's generic-sounding, or if it bears the host star's name (like "HD blah-blah")--then chances are, it’s discovered via Radial Velocity!

Fig. 2: Discovery Method vs. Exoplanet Names
Notes: Exoplanet names are commonly derived from the host star name plus the alphabetical index of the planet by order of its discovery date. Often, the instrument used to discover it are then used in lieu of the star name (for example: Kepler-4 b, or CoRoT-7b)

[Link to the interactive version at Many Eyes]

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These are only some of the visualizations I came up with while playing with the exoplanet dataset for around an hour or so. There are definitely many more correlations you can uncover via the other methods at Many Eyes or other tools. Make sure you also play around with the data and let other people know about the insights you come up with. Head over to Many Eyes and use the same data I uploaded to generate your own visualizations.

Disclaimer:
1) These graphs and visualizations are what we can statistically glean from, given the current data provided. The trends I pointed out in this post will change in the next few years. For example: When Kepler starts to announce their discoveries, the number of exoplanets discovered via Transit Method will suddenly skyrocket and overtake the total number of exoplanets discovered via Radial Velocity (RV). (It will be interesting how to visualize that trend when we add the function of time.)
2) Also, these visualizations does not take into account those exoplanets discovered by a mash-up of two or more methods (such as those exoplanets discovered by using Transit method in tandem with RV).

Links:
Many Eyes
Dataset from Exoplanets.org