soci ated ▁from ▁a ▁larger ▁entity ▁by ▁means ▁of ▁explos ion , ▁collision ▁or ▁d eter ior ation . ▁Mic rop art ic ulate ▁matter ▁describes ▁space ▁matter ▁that ▁typically ▁cannot ▁be ▁seen ▁sing ly ▁with ▁the ▁n aked ▁eye , ▁including ▁particles , ▁g ases , ▁and ▁space g low . ▁ ▁In ▁response ▁to ▁research ▁that ▁concluded ▁that ▁impact s ▁from ▁Earth ▁orb ital ▁de br is ▁could ▁lead ▁to ▁greater ▁ha z ards ▁to ▁space craft ▁than ▁the ▁natural ▁meteor oid ▁environment , ▁NASA ▁began ▁the ▁orb ital ▁de br is ▁program ▁in ▁ 1 9 7 9 , ▁initi ated ▁by ▁the ▁Space ▁Sciences ▁branch ▁at ▁Johnson ▁Space ▁Center ▁( J SC ). ▁Begin ning ▁with ▁an ▁initial ▁budget ▁of ▁$ 7 0 , 0 0 0 , ▁the ▁NASA ▁orb ital ▁de br is ▁program ▁began ▁with ▁the ▁initial ▁goals ▁of ▁character izing ▁ha z ards ▁induced ▁by ▁space ▁de br is ▁and ▁creating ▁mit ig ation ▁standards ▁that ▁would ▁minim ize ▁the ▁growth ▁of ▁the ▁orb ital ▁de br is ▁environment . ▁By ▁ 1 9 9 0 , ▁the ▁NASA ▁orb ital ▁de br is ▁program ▁created ▁a ▁de br is ▁monitoring ▁program , ▁which ▁included ▁mechan isms ▁to ▁sample ▁the ▁low ▁Earth ▁orbit ▁( LE O ) ▁environment ▁for ▁de br is ▁as ▁small ▁as ▁ 6 mm ▁using ▁the ▁Hay stack ▁X - band ▁ground ▁rad ar . ▁ ▁Ep ide mi ology ▁▁ ▁Part ic ulate ▁poll ution ▁is ▁observed ▁around ▁the ▁glo