In a Recent Survey of Stars in the Sky, It

question 100

Multiple Choice

In a recent survey of stars in the sky, it was found that occasionally a star that is normally of constant brightness will slowly brighten and then fade back to its original brightness again over the space of several weeks. What is believed to be the cause of this change in brightness?

• A) massive coronal ejection on a star with abnormally strong magnetic fields
• B) gradual motion of the star through a break or hole between interstellar dust clouds
• C) microlensing by compact objects such as brown dwarfs passing in front of the star
• D) "lighthouse beam" of a slowly rotating neutron star companion

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Definitions:

Intravenous

Administered within or into a vein.

Intravenous

Refers to the administration of medicines, fluids, nutrients, or other substances directly into a vein.

Intrathecal

Pertaining to an injection into the space under the arachnoid membrane of the brain or spinal cord.

Intramuscular

Related to the administration of medication directly into the muscle tissue through injection.