An angiogram uses X-rays and a special dye (contrast) to take pictures of the arteries in your brain, heart, and kidneys. The dye is injected into a small tube or catheter into an artery in your groin or (sometimes) your arm.
As the cloud collapses the force of gravity drawing the cloud inward gradually becomes stronger because the strength of gravity follows an inverse square law with distance. hoâ¦pe that helps.
The formation of a star begins with gravitational instability within a molecular cloud, caused by regions of higher density-often triggered by shock-waves from nearby supernovae (massive stellar explosions), the collision of different molecular clouds, or the collision of galaxies (as in a starburst galaxy).