What's Out There?

With such a vast amount of area, it seems nearly impossible to know everything that is in our universe.  To help with this search the Interstellar Boundary Explorer (IBEX) has been finding neutral atoms out in space since 2009.  IBEX has found interstellar hydrogen, helium, neon and oxygen coming from outside the heliosphere.  Can these atoms from outside be any sort of proof of life beyond our own?  What else will IBEX find and will these findings change our future?

The heliosphere is where the solar system resides.  As a result of the solar winds from the sun, we are surrounded by this protective bubble.  The solar winds are made of charged particles that are able to escape the suns gravity because of their higher energy and temperature.  These solar winds create a cavity-like area that has been named the heliosphere. 

(Artist interpretation of the heliosphere among other things; image from http://www.centauri-dreams.org/?p=3763)

IBEX is the first to discover the interstellar neutral atoms (ISNs) hydrogen, oxygen, and neon (Ulysses discovered helium first).  These atoms are "blown" into the heliosphere.  The movement of the heliosphere and everything within (including the solar system) causes the interstellar atoms to be "blown".  The ISNs are unaffected by the magnetic field of the heliosphere and that is why the atoms are called neutral.

Consisting of only two sensors and a control for them the instrumentation that IBEX has is minimal compared to other spacecrafts.  IBEX has a Combined Electronics Unit (CEU) that controls the two sensors, IBEX-Hi and IBEX-Lo.  The atoms enter the sensors to be read by IBEX.  Upon entering, the atoms meet a filter-like instrument called the collimator which excludes charged particles and excess light that the IBEX does not want to analyze.  The two sensors evaluate the velocity of the atoms to figure out what the energy of each particle is and by using these energies the team can understand what the particles may be.

(IBEX Spacecraft; image from http://www.nasa.gov/mission_pages/ibex/IBEXMediaTelecon1.html)

With the discovery of ISNs scientists can better understand the defensive bubble that surrounds us known as the heliosphere.  This bubble keeps us safe by deflecting dangerous cosmic rays from our surroundings.  It is important to understand the things that protect us in order to maintain that protection if needed.  I believe that the data gathered from IBEX will expand our knowledge of the unknowns of deep space and help us answer many of the questions that have yet to be answered about where we came from and how.

LIGO!

The Laser Interferometer Gravitational-Wave Observatory (LIGO) has become an interesting topic with its research on gravitational wave.

Once again, Albert Einstein has proven to be quite the genius we all know him to be.  Einstein actually predicted that gravitational waves existed way back in 1916.  To find these ripples in space, scientists have constructed LIGO.  Together, the Massachusetts Institute of Technology (MIT) and the California Institute of Technology (Caltech) are working towards the mysterious discoveries of these gravitational waves.

The key component of LIGO is the laser interferometer.  This is the instrument that will be used to find the existing gravitational waves.  Below is a diagram of a laser interferometer:

 

(image from http://www.space.com/5221-scientists-expect-find-gravitational-waves.html)

This experiment needs high levels of precision and steady ground in order to not get excess noise in the data.  For precision,  a laser light is shot at the mirrors.  The laser is shot through a beam splitter to divide the light.  Each part of the beam travels separately down the two perpendicular arms of the system.  Each arm consists of two mirrors in which the light can bounce between them.  The two arms have the same length causing the beams to interfere and not be read by the photodetector.  For the photodetector to read any light, there would have to be some sort of change in the light beams.  Well there is something that does just that, gravitational waves!  The ripples of the gravitational waves causes the beams of light not to interfere and the photodetector is able to read light going through it. These ripples in space are caused by massive events such as collisions of the stars.

The LIGO team has sought out to find the gravitational waves for many years.  When the beam of light of the interferometer is altered and after data analysis, the team will know that they have found gravitational waves.

To get an idea of what the observatory looks like (the long arms are quite noticeable):

Livingstone, Louisiana

(picture from http://www.universetoday.com/46847/ligo/)

 Richland, Washington

(picture from http://www.ligo.caltech.edu/LIGO_web/0405news/0405liv.html)