For years, scientists have tried to explain the Fermi paradox, which says simply that if the probability of intelligent life evolving on other planets is anything greater than 0, there is such a mind numbingly huge number of planets in the galaxy that we would expect the number of advanced civilizations in the galaxy to be astronomical. So, according to the Fermi paradox, where are they?

Another way to express this is the Drake equation. The Drake equation expresses the expected number of advanced civilizations in the galaxy as:

N = N* * fp * ne * fl * fi * fc * L / Tg

So, what is N? Obviously, it can't be a very small number, because if it were too small we ourselves would not exist. But, if the number were much larger than one, we would expect the galaxy to be positively overflowing with advanced civilizations. Considering the milky way galaxy is at least 8 billion years old, and it would take somewhere between 5 and 50 million years for an advanced civilization to fill the galaxy, any other advanced civilizations in the galaxy would likely have been around for a billion years or more and would have long since filled the galaxy. In fact, if that were true, we probably would not be here, because any adavanced civilization would have colonized earth hundreds of millions of years ago, and we would not be here.

The only plausible solution to the Drake equation is that N is approximately 1. Any smaller and we would not exist. Any larger and we also would not exist. So, the mere fact that the human race has evolved on this small blue planet orbiting an unremarkable yellow dwarf star in a quiet corner of the milky way galaxy probably means that the solution to the Drake equation is, 1!

This is incredible news, Kepler has discovered 1200+ new planet candidates, 68 of which appear to be approximately earth sized, and some of those appear to orbit in a habitable zone! Astronomers estimate 80-90% of the candidates will be confirmed as bona fide exoplanets. 

One system, Kepler-11, has 6 planets all orbiting within the orbit of Venus around a more or less sun like star. What is amazing is all 6 planets transit the parent star. Unfortunately the star is approximately 2000 light years away.

Read more here:

http://www.nasa.gov/mission_pages/kepler/news/kepler_data_release.html

Astronomers have located 2 more planets in the Gliese 581 planetary system, just 20 light years from earth. One of the two, Gliese 581 g, is a super earth, approximately 3-4 times as massive as the earth, orbiting in the habitable zone between Gliese 581 c and Gliese 581 d. The newly discovered planet orbits the red dwarf star Gliese 581 in just 37 days. Gliese 581 is a small, dim star, so although Gliese 581 g orbits very close to the star, the predicted mean temperature is in the habitable zone.

Gliese 581 g is also probably tidally locked, so that one side of the planet always faces the sun. On the day side, 581 g is probably a hellish desert. The night side would be frozen in permanent shadow, with an eternal cyclone of convective winds circulating between the day and night sides. However, the planet would be circled in a ring or perpetual twilight, where the balance between day and night might be "just right" for life to survive.

A new planet has been discovered, GJ 1214 b.  GJ 1214 b orbits close to a red dwarf star (GJ 1214) located just 40 light years from earth.  Because GJ 1214 b transits the star, both its size and mass can be determined. 

GJ 1214 b appears to be an ocean world, six and a half times the mass and just over twice the diameter of earth.  Orbiting once every 1.6 days, the mean surface temperature of GJ 1214 b would be between 120 and 280 °C.  Orbiting so close to it’s parent star, GJ 1214 b is almost certainly tidally locked, so that while the surface ocean would most likely be boiling on the “day” side, it would be frozen into a permanent ice cap on the “night” side.  And, between day and night would exist a perpetual storm.  On the “day” side, water would boil and enter the atmosphere, circulating the “night” side where it would fall as rain (near the twilight edge) and snow. The movement of water, constantly boiling on the “day” side and accumulating as glaciers miles thick on the “night” side, would be enough to unbalance the entire planet.

Is there life on GJ 1214 b?

·         There is liquid water present

·         There is plenty of solar energy for life, enough to boil it’s ocean

·         The range of surface temperatures spans the habitable zone

·         Deep oceans would shield life forms from hazardous solar flares and other radiation

·         Turbulent surface conditions would create dynamic disequilibrium, which would fuel complex chemical interactions which could lead to life

Extrasolar Planets

The big news this week is the discovery of the smallest exoplanet yet discovered, Gliese 581 e in the constellation Libra.  The new planet is just twice the mass of earth, and orbits it’s red dwarf parent star in just under 4 days.

Gliese 581 is just 20 light years away and has 3 other known planets.  Extra solar planet hunters are finding more and more multi planet systems around nearby dwarf stars.  Gliese 876, for example, is another similar multi planet system, just 15 light years away in the constellation Aquarius.  55 Cancri is another similar system, except it is a yellow dwarf binary system.  In spite of orbiting very different parent stars, these multi planet solar systems are structurally similar to our own solar system.

In other news, a recent article suggests our galaxy is probably dirty with sister earths, greatly increasing the likelihood of finding life on other planets.

Mercury

MESSENGER has finally sent back new images from it’s 3rd flyby of Mercury.

Earth

China has announced specifications for a new super heavy lifter.  The new launch platform will weigh 675 tons, and be capable of launching a 12 ton payload to GEO or 25 tons to LEO.  ESA has launched 2 new space telescopes, new space telescopes, Herschel and Planck.

Moon

India’s Chandrayaan-1 has sent new images of the moon to probe the possible existence of water in permanently shadowed craters.

Mars

Spirit has been plagued by troubles.  First, a glitch caused a loss of data from memory.  To make maters worse, Spirit has become badly stuck in loose sand.  Mission engineers are still working on a plan to try to get out of the difficult situation.

In other Mars news, the Russian Phobos-Grunt sample return mission to the moon Phobos will also include a sample of microbes from Antarctica to see if they can survive the trip.
 

DSR 2.8

The big news this week is the discovery that Theta 1 Orions C, a bright star in the Trapezium in Orion (that is a collection of bright stars in the Orion nebula, just below his belt) is actually a binary star.

What’s more exciting is the discovery was made by the VLTI in Chile, an optical interferometer with amazing resolving power.  Light from the 4 telescopes can be combined in a way to increase the resolving power to be equivalent to a single telescope with a much larger mirror.

In other space imaging news, an images of exoplanet HR 8799b was found in 10 year old images collected by the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) instrument on Hubble.  It turns out the image had been collected many years ago, but the existence of the planet was not known at the time.  HR 8799b was officially “discovered” at the Gemini North observatory in 2007.  Later examination of the NICMOS images revealed the planet actually was imaged much earlier.  In astronomy, it’s actually fairly common for some celestial object to be “discovered” and then later found in much earlier images.  The star HR 8799 has 3 known planets, each with 7-10 time the mass of Jupiter orbiting far from their sun.  HR 8799 is about 1.5 times the size of our sun.  The inner planet has a nearly circular orbit, and although the shapes of the orbits of the other planets are not known, they most likely orbit in a roughly 1:2:4 resonance.  Although the planets are much larger than the gas giants of our solar system, there are many striking similarities between HR 8799 and our own solar system, including the possibility of undiscovered terrestrial planets in the inner solar system. 

Meanwhile, on Mars, Spirit set a new driving record (for 5 wheel driving) and Opportunity is using the RAT, MI, Mossbauer Spectrometer, and X-Ray spectrometer on a new target found on Meridiani.  Some of these instruments have not been used in years.  As usual, HortonHeardaWho has posted some terrific images on his flickr photo stream, it is definitely worth taking a look.

In other news, LISA, an spacecraft designed to detect gravity waves scheduled for launch in 2018, should also be able to detect and measure the mass of near earth asteroids as they pass by.  They are predicting they will be able to measure 1 or 2 NEAs per year.  Also, Paragon Space Development Corporation plans to grow plants on the moon

DSR 2.7

Online Fun

NASA is promoting a tournament to nominate the greatest NASA mission of all time.  My vote will be for the Mars rovers, of course.

The Moon

China has announced plans to land on the moon by 2013, and Obama has declared his support for a a return to the moon with a manned mission.

Mars

Images from MRO’s HiRISE imaging system have provided more clues of recent water activity in some gullies on mars.

Deep Space

Kepler has launched!  Hooray!  It’s just a matter of months (well maybe years) until we start finding M class planets around other stars.

And, speaking of M class planets, astronomers have discovered a binary black hole system.  Great place to work on your tan.  Some people prefer to tan with good old UV, but I like x-rays or even the occasional soft gamma ray when you can get’em.

There is also a fascinating new theory that, not only may there be life on the asteroid Ceres, but life may even have evolved on Ceres first and been transferred to the earth (during the late heavy bombardment)

Deep Space Report 2.3

BBC: Galaxy has 'billions of Earths'

Extrapolation done by Dr. Alan Boss of the Carnegie Institution of Science.  Based upon the 300+ planets found so far he has estimated that there are perhaps billions of earthlike planets in the galaxy.

So using his number that places us halfway through the Drake equation.

N = R* × f_p × n_e × f_l × f_i × f_c × L

[link: Drake Equation]

Of course the numbers get harder to know (or estimate) the further towards the right side of that equation.  But just think we didn’t even have the data to make an educated guess five years ago.

Mars

Last week I briefly mentioned the methane burp on Mars.  This has reopened a general discussion of the implication of the presence of methane on Mars.  This is a really big deal, because there are only 2 possible sources of methane on Mars, volcanoes or microbes.  Both are very exciting possibilities, but it turns out that many Mars experts have concluded that a biological source seems to explain the data better.  That means life on Mars people.   This is a really big deal.  There was an interesting discussion last week on Science Friday, available in a podcast.

Also, Spirit has a scary glitch.  It failed to respond to commands to move, and then didn’t store any data in non volatile memory, so the whole day was lost.  The MER team isn’t panicking yet.  This may just be a one off failure, or it could be the beginning of the end for the aging spacecraft.

Saturn

Cassini captured new images of a region of lakes near the south pole on Titan. By comparing these images to earlier images, they have found seasonal changes, which include very strong evidence for lakes and cloud formations. 

Deep Space

The Planetary Society has sent their new “Beyond the Moon” roadmap for future plans to explore space to congress.  The plan focuses mostly on government funded exploration, with Mars as the eventual goal.  Of course the long term goal is to establish some kind of permanent human presence in space, but suffers from the perennial problem of lack of justification.  I think if we really want to go into space, we need to let private industry lead the way.  The justification, as always, is profit.  And there are vast riches out there to be won, we just need to enable private industry to go get it and then get out of the way.   Companies like Armadillo Aerospace and Virgin Galactic are already making a good start.

Also, new observations of a wild exoplanet, HD 80606b, that passes within .03 AU of it’s host star every 111 days have recorded a planet wide temperature increase of over a thousand degrees in just 6 hours.

DSR 2.1

Luna

China's Chang'e-1 space probe has adjusted its orbit to just 200 km above the surface of the moon.

Mars

After last week's discussion of the possibility of long term climate cycles, and maybe even life on Mars, this week researchers at Cal Tech published a new study indicating that Mars' axial tilt could produce climate cycles on the order of 100,000 years in length, that's just under 50,000 mars years, by the way.  Glad to see great minds think alike.

Asteroids

Bulgarian astronomers have discovered a new asteroid this week, 2008 WN96.  The asteroid is estimated to be 2 km diameter, which is pretty large for an asteroid discovered so recently, with an orbital period of 3.2 years.

Jupiter

In a new report, University of Washington oceanographer Robert Tyler has calculated the heat required to maintain a liquid ocean on Europa could come from waves generated from the ocean itself.  An axial tilt of less than one degree would be sufficient to produce enough heat to keep the ocean liquid.

Deep Space

CO2 has been discovered for the first time in the atmosphere of an exoplanet, HD 189733b, 63 light years away.

 Deep Space Report 1.11

Cool Stuff

Check out this interactive map of nearby stars:

Luna

Chandrayaan-1 has begun remote sensing of the moon, and has also landed a remote probe, although apparently the probe had a "hard landing" that "terminated it's functioning."  But, let's focus on the success, they DID land the probe on the moon!

NASA has also tested some more lunar rover designs, and more importantly two separate ISRU methods to extract oxygen from lunar material.  This is a really big deal, not only can lunar oxygen be used to breath, it also makes up the bulk of most rocket propellants.  Future missions to the moon might use lunar oxygen as propellant for a return trip.

Mars

Spirit has been caught in a dust storm which has drastically reduced the amount of solar power generated by its solar panels.  NASA has commanded the rover to take some severe power saving measures, including shutting down the heater to the thermal imager.  The thermal imager is susceptible to cold, so shutting down the heater may cause permanent damage to the imager.  As of last Friday, Spirit was low on power but still communicating with NASA.

Deep Space

ESA's Ulysses spacecraft is about to end it's 14 year mission to study the sun.  Its RTG power generator is beginning to wane, and soon it will lose the ability to operate.  Launched in 1990, Ulysses first traveled to Jupiter and used a gravitational assist to launch into an orbit which took it over the poles of the sun.  It has orbited the sun 3 times since then, it was originally designed for a 5 year mission.

Beyond

Amazing images of 2 extrasolar planetary systems were published last week.  A Jupiter size planet orbiting the star Fomalhaut, 25 light years away,

and an amazing 3 planet system around HR8799, some 140 light years away.

SEE not infer.

The technology does not use glass lenses nor reflective mirrors but an advanced form of a pinhole camera, the "pinhole" technique is called Fresnel zone plates.

New Scientist article.

The technical hurdles would be tricky but nothing unbelievable.

Essentially we would need to launch two spacecraft.: one is the "lens" and one is the "receptor".  The focal point using the Fresnel method is kilometers away from the lense, ergo the two spacecraft solution.

Go read the whole article, just fascinating.

Feeds right into this post: Planet Hunting, The Next Generation - The Lyot Project

Accelerating change is going on all around us.  We see it in entertainment from computer games to movies.  We see it in telephones as they keep getting smaller and more feature rich.  We see it in cameras and music players and personal GPS devices.  Etcetera, etcetera, etcetera.

All of this creeps into our lives and becomes ubiquitous.  The changes quickly becomes invisible, expected and, in a weird sort of way, un-important.

But accelerating change is also affecting the sciences.

For example the hunt for extra-solar planets.  The first one discovered was in 1991.  Since then there has been a rapid pace of discovery.  The bulk of the discoveries essentially done by inference: careful detection of the wobbling of the star around which the planet[s] orbit. 

So the point here is that before 1991 we had NO evidence of planets orbiting other stars.  In theory we were 100% sure (or so close as to make no difference) that most stars had some planets, but we had no direct evidence.

Now there has been over 250 planets identified.

But wait that's not all!

Now there is a new technology under development by the Lyot Project, it's goal to create the necessary instrument and associated software to remove starlight from images thus allowing the much fainter planets to be viewed directly.  Astronomers will no longer need rely on inference to discover new planets.

This would be a remarkable achievement and would allow for a much greater number of planets to be discovered.  It would probably also allow for the discovery of Earth like planets and the reading of spectrums from the planets themselves.

What would the reactions be if we found a planet with a spectral analysis that matched Earth?  Orbit, temperature, water, oxygen?...

Would that spur some research into a viable star probe?  Just asking...

Accelerating change is cool.

Sites of interest:

• Extrasolar Planets Encyclopedia
• How do astronomers find planets orbiting other stars?
• The Futurist is a big proponent of observing the accelerating change going on in many facets of our world and even in places we don't normally look. There are several entries that discuss the accelerating change that is going on in telescope technology.