All Space Considered, June 2014

Lots of little stories this month and just one big one.  Unfortunately that big one called BICEP2's results regarding gravitational waves in the cosmic microwave background into question.  While the results from March may still hold up, at the moment, scientific consensus does not exist because of the possibility of alternative explanations for their observations.

Jupiter's red spot is shrinking.  Compared with the earliest known pictures of Jupiter, the red spot is much smaller and the shrinkage seems to be accelerating.  This was bound to happen.  Storms can't last forever.  However, the disappearance of such a definitive identifying marker would still be a sad occasion.

Magnetars can be big.  Well, compared to main sequence stars, they're still small, but they can be bigger than originally thought.  One was found that was larger than previous theory allowed and the explanation seems to be that the mass can come from a sister star in a binary system.  The angular momentum from the additional mass is enough to help the neutron degeneracy pressure hold up the collapsing star and prevent it from becoming a black hole at higher masses than previously thought possible.  This was the best theory since the large magnetar was observed.  The big news, however, is that they actually observed the sister star and its characteristics match predictions of this theory.

Russia and the U.S. fighting over space.  It's nothing like the Cold War, but Russia's recent actions in the Ukraine have resulted in U.S. sanctions on Russia, meaning what were routine cargo lifts to the International Space Station are under conflict.  Some sharp words were exchanged and Elon Musk's SpaceX may come to the U.S.'s rescue.

Illustris, a truly ginormous simulation of the Universe from quite early until now, was recently run.  In this simulation, dark matter, gravity and the dynamics of stars (from formation to supernovae) were all taken into account.  The simulation was successful in re-creating much of the Universe as we see it.  Spiral arms in galaxies, large scale galaxy clusters and the interstellar medium all matched the observable Universe to pretty remarkable accuracy.  Once they work out the kinks, the team that ran the simulation is even making the hundreds of terabytes available to the public.  Get your hard drives ready!

The International Space Station is now broadcasting live.  In addition to pretty mind-blowing pictures...well, just be happy with mind-blowing pictures.  You can probably do some extra mind-blowing by manipulating some of the pictures, but if you're reading this, sunrise in space probably tickles your fancy just a little.

The exoplanet revolution continues.  A new type of exoplanet was discovered.  Previously, exoplanets were generally thought to be either small and rocky like Earth or big and gassy like Jupiter.  Kepler-10c, however, is big and rocky.  With a diameter 2.5x that of Earth and a mass 17x that of Earth, it is the largest rocky object we've observed, putting it in a new class known as Mega-Earths.  This challenges our current planet-formation theories, as anything so large should have enough gravity to hold on to a thick atmosphere.

All Space Considered, September 2014

Here's a quick summary of what we learned about at All Space Considered, September 2014.  I'm sure I've forgotten something, as I didn't take notes.  Hopefully the other attendees can help out a bit.

Comet Chasers

The NASA probe Stardust flew to a comet.  As if that weren't impressive enough, it collected actual comet material while it was there.  As if that weren't impressive enough, it came back to Earth with its samples intact.  That was actually several years ago, but, as anyone who follows science much at all knows, it's one thing to collect data and another to analyze it all.  Just this past month, due to the magic of the crowdsourcing effort Stardust@home, something new was discovered in the data.  It turns out some of its collectors not only got comet particles, but captures some of the Interstellar medium as well.  As if that weren't impressive enough, the material has been analyzed and contains lots of things that weren't expected.

The ESA, not to be outdone, has sent Rosetta up to an comet.  Some very impressive pictures have been sent back already.  However, the best is yet to come.  They will be landing a secondary probe on the surface of the asteroid.  At such proximity, much more can be determined about the composition of the comet than from afar.  The lander's instruments will provide quite a wide range of data, including internal and external structure of the comet as well surface and internal material composition.

Aside from the sheer engineering awesomeness of human-made objects syncing up with objects moving thousands of times faster than most humans ever will (at least relative to Earth), what's so great about studying comets?  As the solar system formed, much of the inner core material went to make planets and moons.  Asteroids are great objects to study because they represent the rocky material that was present when the solar system formed.  However, they are generally far too close to the sun and too small to hold onto any non-rocky material.  Comets, which generally come in from the Kuiper Belt or Oort cloud, originated much farther away and are much more likely to preserve this truly ancient material.  This is somewhat ironic because the Stardust finding is interesting because the interstellar medium it picked up is hypothesized to be newer than any similar material gathered before.

Laniakea

The name means "immense heaven" in Hawaiian.  My guess is the people who came up with the word had no idea just how immense the heavens could be.  Recently, a gravity map of sorts found an even larger grouping of galaxies to be gravitationally bound than previously thought.  Most are well aware that Earth is part of the solar system and that the solar system is part of the Milky Way galaxy.  For some time, we've known the Milky Way to be part of a larger grouping called the "Local Group," which is itself part of an even larger grouping known as the Virgo supercluster.  Previously, it was thought that this was the largest structure to which the planet Earth belonged to, as anything beyond the Virgo supercluster was not gravitationally bound, meaning that it would, in time, drift away.  As it turns out, much more is gravitationally bound to the Milky Way and Virgo supercluster than we thought; and that's what was discovered.  It's really worth looking at the animations of the map.  It's quite fascinating and, if you're into pyschedelics, psychedelic. 

Extremophiles in the Antarctic

Yet more extremophiles were discovered.  These happened to be inhabiting an under-ice lake that hasn't seen the light of day for well over 100,000 years, possibly as long as 1,000,000 years.  All sunlight is completely blocked at this depth by the ice, so there is no chance of photosynthesis.  Yet over 4,000 species found some way to live and reproduce.  The intense interest in extremophiles on Earth is a result of a search for life in outer space.  The conventional wisdom had long been that certain environments, in fact most environments in outer space, just aren't suitable for life.  However, the more we explore similar extreme environments on Earth, the more it looks like life can sustain itself just about anywhere.  Further, these sunless, under-ice lakes are likely to exist on the Saturnian moons Enceladus and Titan as well as the Jovian moon Europa.  I was personally slightly disappointed to find out these extremophiles were dining on other life.  It reduces the chance of such extremophiles being actual initiators and colonizers.  However, Titan at least does have vast stores of hydrocarbons along with its under-ice lakes of water, so I should reserve judgment.

Mars parachute

While life on outer moons is certainly tantalizing, exploring Mars is far more cost-effective, both in terms of time and money.  NASA tested its LDSD ("low density supersonic decelerator") technology and released some hi-res video of the test.  The need for this new technology is a result of ever-increasing payload sizes to the red planet.  As we want to explore more and more, we need bigger and bigger vehicles, more and more instruments and, eventually, life support.  Mars's atmosphere is a unique challenge.  It's far less dense than Earth's, so the drag that can be accomplished by any sort of parachute is far smaller.  However, there is an atmosphere, so we can't just plop ourselves down like we did on the moon.  While the thing that looks most like the kind of parachute we're used to disintegrates in the video, the primary parachute did deploy successfully and the exact rocket fire to spin the craft up and down were pretty impressive.

Dave Doody from Cassini

 So the big treat of this edition of All Space Considered was the appearance of Dave Doody, a Lead Engineer at JPL who works a lot on the Cassini mission.  The main bit of news he provided was that funding had been approved by NASA for Cassini to fulfill the entirety of the Solstice mission.  This would allow Cassini to continue collecting data on Saturn until it literally runs out of fuel, at which point, the craft will be set to plunge into Saturn.  The bulk of what we know about Saturn and its moons has come from the Cassini mission.  We've discovered huge water geysers spewing out of Enceladus, hydrocarbon lakes on Titan and gotten absolutely breathtaking photos of the north pole's hexagonal storm.  What the Solstice mission promises may not live up to such grandeur, but is pretty exciting just to think about.  The probe will be inserted into a polar orbit that will take it between Saturn and its innermost ring, passing at a distance about 1/10th that of the distance from the Earth to the moon.  While quite audacious, this is being done by the team that inserted Cassini into orbit within 1s of when it was predicted and put a probe down on the surface of Titan.