Don’t capitalize neutron; it’s a common noun (used here as an adjective), not a proper one.
Either spell out the whole number or use only numerals. (For academic stuff, numerals are preferred, but writing about science in a non-academic context should be treated as other normal prose.) Write one thousand trillion or write 1,000,000,000,000. (If you really want to do science writing the right way, write the number in scientific notation — which I can’t do here because WordPress doesn’t want me to use exponents — as one times ten to the twelfth power.) That long string of zeroes does look impressive and makes a point to people who would otherwise have no clue just how big one thousand trillion is, but using the numeral also runs the risk of scaring away math-phobes. (“I majored in English — you do the math.” *rolls eyes* Please don’t make me go on yet another bloggish tirade about the stupid-headed wrongness of believing only people who don’t know grammar from their own ass are capable of understanding mathematics and numbers in general.)
Change your (possessive pronoun: belongs to you) to you’re (contraction of you are).
Magnetars are a special form of neutron star. Their magnetic fields are an unbelievable one thousand trillion times stronger than the magnetic field you’re sitting in now.