Where are the missing stars?  A new mystery surrounding globular clusters has arisen from the latest Hubble Space Telescope data.

NASA's Hubble Space Telescope has been looking at globular clusters in the Fornax Dwarf Galaxy.  They have discovered that the globular clusters there appear to be identical to globular clusters found in the Milky Way.  This implies that globular cluster formation is the same in different galaxies.  But this poses a problem with a leading theory.

Globular clusters were once thought to contain stars that were all born about the same time.  But today we know that there were two separate populations.  The second generation of stars in the clusters contain up to 50 to 100 times more nitrogen than the first.  The number of second generation stars is also much higher than the first.

The leading theory suggests that a large amount of the first generation stars were ejected from the cluster.  This would account for the difference in population proportions between the generations.  In the Milky Way, the ejected stars can easily be assumed to be with other old stars in the halo.  But in the Fornax clusters this cannot be the case.

The Fornax clusters also contain two generations of stars made up with the same differences in nitrogen as those clusters found in the Milky Way.  The population proportions between the generations are also the same.  But the Fornax galaxy does not have enough old stars to account for any stars being thrown out of the cluster.  If first generation stars were thrown out of the clusters in the Fornax galaxy we would see them.

Scientists will now have to revisit why there are differences in the generations of stars in globular clusters.

The Van Allen belts are charged particles collected together by Earth's magnetic field.  The inner belt stretches from 400 to 6,000 miles above the Earth and the second from 8,400 to 36,000 miles above the Earth.  They move in response to incoming radiation from the sun.  Sometimes the belts can swell putting low-Earth orbit satellites in danger from radiation.  By understanding how the belts work. scientists can help protect these satellites from harm.

In 2012 NASA launched its Van Allen Probes which are now helping us understand the belts in detail for the first time.

The inner belt is made up of mostly protons.  The outer belt is made up of energetic electrons.  But what causes the gap in between them?  The Van Allen Probes have discovered a barrier that is impenetrable, blocking out even the fastest moving electrons.  But what causes the barrier?  They looked at various possibilities.

The first possibility was human generated.  This was dismissed.  The second was physical, the shape of the magnetic field.  This was also dismissed.  It was determined that some other space particle was at play.

The Earth has another particle structure surrounding it, the plasmasphere.  The plasmasphere is a large cloud of cool charged particles and fills up most of the outer atmosphere starting at about 600 miles above the Earth and going out to near the outer edge of the outer Van Allen belt.

The particles of the plasmasphere cause the particles in Van Allen belt to scatter, but the effect is fairly weak.  Normally, the interaction of the two would not be enough to keep the electrons in place.  However, the radiation belt electrons move very quickly in giant loops around the Earth, but their movement toward Earth is slow slow and gentle.  The motion towards Earth is so weak that the plasmasphere is much stronger in comparison and acts as a barrier.  During a large solar disturbance, the outer Van Allen belt can actually move into the usually empty space between the two belts pushing into the plasmashpere.

Scientists continue to study and analyze the data from the probes to help understand how these radiation belts work, what impact they have on the atmosphere and ozone layer, and learn more about the magnetic fields and plasma that make up most of the Universe.

Quasars are energy produced as something is sucked into a supermassive black hole.  Supermassive black holes are found a centers of galaxies.  As material falls into the black hole, long jets of hot material are shot out into space along the black hole's axis of rotation.  These are quasars.  It is believed quasars were at the center of all galaxies early in the Universe as the galaxies were young and the black holes at their centers had plenty of material to feed on.

A team from the University of Belgium used ESO's Very Large Telescope (VLT) in Chile to study 93 quasars that were active when the Universe was about a third of its present age.

The team discovered that some of the quasars were aligned to each other even though they were billions of light years apart.  This prompted them to examine the rotation axis of the black holes.

In the early Universe, galaxies were not equally distributed but instead form a cosmic web of filaments around areas of empty space.  This is known as the large-scale structure of the Universe.

The results from the VLT indicate that the quasars tend to be parallel to the large-scale structures along the filaments.  This means the black holes would have to point along the the direction of the filaments.

The probability of this being a result of chance is less than 1%.  The results indicate these alignments are on a greater scale than previously imagined and hint there may be something missing from our current models of the cosmos.

Despite the fact that the Philae lander's batteries cannot get enough sunshine to recharge and the landing part of the mission is finished, Rosetta itself continues to gather science.

On 3 December the spacecraft will move down to an altitude of 20 km above the surface for 10 days.  it will then return to an altitude of 30 km.  During this time Rosetta will collect gas, dust and plasma as well as map large parts of the nucleus at high resolution.

As the comet moves closer to the sun, Rosetta will be the first spacecraft to study up close the effects of the sun and what activity takes place.  The comet makes its closest approach to the sun on 13 August 2015, 186 million kilometers from the sun.  Rosetta will be able to move between orbits if activity on the comet increases as the comet nears the sun.

As for Philae, attempts to get a signal will take place periodically.  As the comet gets nearer the sun, illumination on the surface will increase and it may be enough to recharge the batteries, although this is far from certain.