February 25, 2011

Tunnels Between the Stars

In an issue of Green Lantern Corps, entitled "Recharge" from way back in 2006, a nemesis called "The Spider Guild" sneaked to the home planet of the Green Lantern Corps by passing through a wormhole connecting the stars. These tunnels between the stars are called "The Subspace Web". By entering another star (or blackhole) from a different sector of the universe, the 'spiders' traversed through subspace web and then emerged directly from within Oa's sun and attacked the Green Lantern's base "from out of the light".

It's all Science Fiction, so far. Right?

Now for the Science part.

A recent study suggests that wormholes might exist between distant stars. However, it's not easy to detect if a star could harbor some passageway hidden deep within its center. But the scientists are saying that they could be distinguishable from normal stars (or even from normal neutron stars). And it's because these wormholes are not empty tunnels, rather they contain a perfect fluid that flows back and forth between the two stars, giving them a detectable signature via their pulsations.

Wait. It's still Science Fiction!

Nope. Actually, real scientists and astrophysicists are saying this. See for yourself on their ArXiv paper. And take note: Kepler has detected a lot of pulsating stars in their Asteroseismological studies. Yes, Kepler also deals with Asteroseismology--the science that involves probing the interiors of stars and quantifying their global properties, such as radius and age, through observations of normal modes of oscillation. So, ya never know! Our good ol' Kepler might discover some wormhole-bearing stars! Heh!

Now back to the fiction. To cut a long story short, by sheer teamwork, inspired by a massive recital of their green lantern oath (in brightest day, in blackest night...blah...blah), the Green Lantern Corps managed to push back the invading marauders back into the star--including the star itself! Their own sun got pushed into the wormhole-tunnel from the outside-in and was destroyed along with the Spider Guild's nest. So now, in that episode, the green lantern's planet Oa has actually become a starless planet, a rogue planet!

And there you have it, folks. Just a brief excursion in the world of scifi on a friday night! Happy Friday!

A Star Harbouring a Wormhole at its Center (PDF)
Stars Could Have Wormholes At Their Cores (Tech. Review)
the possibility of wormholes between stars (Physorg)

February 24, 2011

Exoplanets are not Planets

How long will exoplanets keep on destroying our predefined notions? Just a few days short of smashing our theories of planetary formation into smithereens, now we have two exoplanets sharing one orbit.

According to the International Astronomical Union (IAU) a planet should clear its orbit of other objects. This condition was a source of heated debate among astronomers that rages on to this very day. It was this alienating third criterion that dethroned Pluto and other dwarf planets from planetary status.

So when I heard that KOI-730's exoplanets were sharing orbits, my first reaction was, “Hey wait a minute...if we try to apply the ‘official’ definition of 'planet' to these exoplanets, they would not be planets at all!”

This is just one instance, but i'm sure there are many derivatives of the case of KOI-730's co-orbiting exoplanets that "share" orbits with other objects. Think of intersecting resonant orbital paths, or locked LaGrangian exoplanet orbits, or exoplanets still in the process of clearing out debris in their path. (It would take millions of years for young planets to clear their orbital zones, mind you.)

I’ve always thought that exoplanets are planets. But today, I'm rethinking that. Yes, exoplanets continue to surprise us, and it's for that reason that I once concluded, Exoplanet is the new 'Planet' by virtue of the awe and wonder that they instill upon us. But now, I’ve come to another realization: Exoplanets are not Planets, and that is liberating. It frees the mind from a limited way of thinking, because the mindset needed for understanding exoplanets is different. Exoplanet discoveries forces you to unlearn, and it frees your mind from the confines of your own star system. Exoplanets require a novel way of thinking. And that is why I love exoplanets so much. They make us think in new ways. Exoplanets make us think outside the sphere! And all that is possible because of Science.

It frustrates me when some astronomers deny dwarf planets of being planets, and yet speak of exoplanets as planets in a carefree way. I want to avoid being annoyed by such inconsistent mindset. So I am letting go of the debate about planets. (Of course, I still consider dwarf planets as legit planets) I will simply let planets be planets, and exoplanets be exoplanets. Just that. I will not try to make exoplanets fit in as planets. I will not even attempt to redefine what a planet is, or grumble about its flawed definition. In fact, I'd rather we keep the current planet definition the way it is now. Let it be a reminder, a tainted bygone--an old ugly chapter in the history of Astronomy.

Perhaps someday, a new definition of the planet will emerge, one that is more universal, that will encompass exoplanets as well. But for now, we are experiencing a temporary chaos brought about by the "growing pains" in our effort to understand the universe.

But until then, with the narrow-minded planet definition we have arrogantly locked ourselves into, who can say with certainty that exoplanets are planets?

This is a new era of planetary thinking. Humanity’s concept of the Planet is of the past, but Exoplanets are of the future.

NewScientist: Two exoplanets found, sharing one orbit
Life, Unbounded: Make Me a Planet
Theories of Planetary Formation, Busted
Exoplanet is the new 'Planet'

February 14, 2011

Sunless Biospheres

Today, I heard about the newly discovered sets of undersea vents found near Antartica. I can’t help but remember an article just a few days ago that mentioned the possibility of rogue planets harboring life. Although the theory is based on computer simulations, the researchers say that a “Steppenwolf planet” wandering in outer space like a “lone wolf”--may have liquid oceans if the water were heated from below by the planet's core and insulated from above by a thick layer of ice. A sunless biosphere.

I wonder how long these Steppenwolf planets will manage to keep the heat inside it's shell of ice to give enough time for life to synthesize from within its undersea vents. Time and luck is definitely a factor. Nevertheless, there’s a lot of planets out there; and not even counting exomoons in the equation, Hydrothermal Vents may be common for those planets that may have ample amount of water and enough internal heat as a source of energy. And judging from the resiliency of life as demonstrated by extremophiles thriving upon the energy and minerals around these vents, it makes me even more convinced of the possibility that life may be common in the universe.

Perhaps Life is not wholly dependent upon stars and suns. Perhaps Life just needs is a source of energy in any which form it is available and it will take hold given enough time and space--which in this case, is a Sunless Biosphere of a Steppenwolf Planet.

More deep-sea vents discovered
Rogue Planets could harbor life

February 9, 2011

Transit Light-Curve Signatures of Artificial Objects

Hot on the trail of Transit Light Curve (TLC*) Mechanics, I’d like to follow up my previous post dealing with transits by featuring this topic: Transit Light-Curve Signatures of Artificial Objects. It's a "Dysonian SETI" paper written by Luc Arnold from way back in 2005 that also mentions possible signals that might be encoded within transit light curves, and hints at the detection of ringed planets as well.

The main idea is that non-spherical objects have different light curve signatures and should be distinguishable from the usual patterns of a transiting planet.

Because hundreds or thousands of people are now looking at light curves via the Planet Hunters project, I thought it’s a good idea to post what the paper says about unusual light-curve patterns that might be caused by the transit of artificial planet-sized objects. Who knows? Perhaps the common folk hunting for planets might end up finding Civilizations as well!

So, dear planet-hunter slash civilization-hunter, start familiarizing yourself with the sample patterns I compiled below (as a quick reference) while you're classifiying light curves at PlanetHunters.org. Good luck with spotting that Kardashev Type II Civilization !!!

* TLC Mechanics/Dynamics, A sub-field of the science of planet-hunting focused on the study and analysis of Transit Light Curves

Bow Shock Transits

Just a quick note to all the Citizen Planet Hunters (CPH) involved in Zooniverse's Planet Hunter project. Based on this paper, Transit Variability in Bow Shock-Hosting Planets, exoplanet bow shocks can affect the light curve during transits. There will be small variations in the light curve caused by the bow shock when the planet’s magnetosphere adjusts in response to "variations in the surrounding ambient medium."

In essence, the variations and irregularities are caused by "shock transits". We should be aware of them when analyzing light curves. I believe that many of the exoplanet candidates in Kepler's data release have bow shocks because most of them lie very close to their respective host stars.

Also, I think that bow shocks are bright, especially when the planet plows through material from a massive coronal mass ejection (CME). Hence some bow shock transits should cause a spike (instead of a dip) in the light curve. This spike, I assume, should occur a short moment before the planet crosses the star, or shortly before the "ingress".

However, there's a disclaimer I'd like to add to this post: The paper says that the effect of the shock transit shows up in the near-UV light curves. But Kepler's light curves are photometric optical light curves, so i am making an inference that effects of bow shocks might show up in Kepler's optical light curves as well. (I will dig more about this topic and post as soon as i get more info).

But For now, take a look at the snapshot below and note the pattern of how the bow shock's transit shows itself in the light curves. And more importantly, a reversed pattern might show up for planets that have "behind shocks". The main principle is that bow shocks can affect light curves.

Good luck! And don't be shocked if you find yourself one of the co-discoverers of a planet with an amazing bow shock!

February 2, 2011

Kepler's Groundhog Day Exoplanets

Groundhog Day, year 2011. The Kepler Mission team announces new exoplanet discoveries and releases data on more than a thousand new exoplanet candidates giving a clear sign of what is to come: There will be more exoplanet discoveries, again and again, over and over, for decades onwards.

The latest exoplanet announcements from Kepler are six “Neptune-type” planets all of are in tight orbits around their parent star called Kepler-11.

But even more exciting than the announcement of these six planets around Kepler-11 is the Kepler team's public release of data that contains more than a thousand new exoplanet candidates that have yet to be confirmed. Approximately 90% is expected to turn out as true exoplanets from this data set alone. They would most likely include many super-earths, and even more earth-size planets some of which lie in the habitable zone.

There will be more exoplanets in the coming months and years. I cannot even fathom what this would mean for our generation. We are witnessing a historic event in humanity's quest to find our place in the universe.

Consider this: in the Cygnus constellation alone, an area in the sky smaller than a coin held at arms length harbors thousands of planets, if not millions. A few thousand of those planets are as small, or smaller than our own, orbiting within the Habitable Zone. I cannot even dare say (because it's an understatement) that at least one of these worlds could harbor some form life.

Are you having an existential shock now? Well, get used to it. This will happen over and over again.

Happy Groundhog Day!

Bounty of Multi-Planet Solar Systems
It’s Full of Planets