My first and last letter is a type of cow. My two middle letters is a state in USA. What am I?

In the cold, stormy night my gaze might save your life.

Mars, Antarctica, Mount Everest, or your Great Aunt May who offers turnips and unsweetened lemonade when you visit.

I stretch through space, yet hold things tight, a cosmic spiral of distant light.

I wander far on wings of mail, a lightweight traveler, thin and frail. Stamped with care, no wrapper's hide, just ink and views from lands I've spied. From beach or peak, a memory's trace, greetings short in a pictured space. No box confines my brief delight, connecting hearts through day and night.