There is a remarkable disarray in understanding what happens on small scales. That pertains for both observations and theory. Whether this constitutes a CRISIS or not is another issue, but it is an INTERESTING situation.  

  

  It seems that some "solutions" of the crisis are worse than the problem with the cusps and satellites themselves. If remedy kills the patient we may better let him live with the disease.

 

Standard LCDM model can explain the discrepancy between the large number of dark matter satellites and the number of dwarfs in the Local Group. This still leaves plenty of questions: HVC or not to HVC, lensing on the substructure, survival of disks, etc.

Two key areas: Z=7-10 - how dwarfs started and Z=0 - how they ended.

Interpretation of rotation curves of DM-dominated dwarfs and LSBs is a more difficult problem than we expected. In more than 1/2 of the cases standard model gives reasonable fits. It fails in some cases, but the situation is very murky.

 

 

 

        Observations we need:

rotation curves and velocity dispersion in red bands (old population)
velocity dispersion for dSph up to few kpc
HVCs far from galaxies and around other galaxies
Dwarf Satellite systems around other galaxies

 

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