To solve this problem, we need to understand how traveling around the world westward affects the number of days experienced and the local date upon return.

Number of Sunrises and Sunsets Experienced:

You experienced 365 sunrises and sunsets during your westward circumnavigation.

This means, according to your own reckoning (on the ship), 365 days have passed.

Effect of Westward Travel on Calendar Date:

When you travel westward, you are moving against the Earth's rotation.

For every 15 degrees of longitude you travel westward, you effectively gain one hour.

Circumnavigating westward once, you gain a total of 24 hours, or one full day.

Comparison with the Port's Calendar:

While you have experienced 365 days, the port (which did not move) has experienced 366 days.

This is because, as you gained a day by traveling westward, the port's calendar moved ahead by one additional day compared to yours.

Calculating the Date at the Port:

You departed on January 1st.

You experienced 365 days during your journey.

The port experienced 366 days during the same period.

Therefore, when you return, the port's date is one day ahead of yours.

Conclusion:

Upon returning, your ship's calendar says January 1st.

The port's calendar says January 2nd.

Therefore, the date at the port when you return is January 2nd.

Visual Representation:

Your Experience (Ship's Calendar):

Depart: January 1st

Days Experienced: 365

Return: January 1st

Port's Experience (Port's Calendar):

Days Passed: 366

Date upon Return: January 2nd

Key Points:

Traveling westward around the world results in gaining one day compared to the starting location.

While you experience 365 days, the port experiences 366 days.

Therefore, the port's date is one day ahead when you return.

Final Answer: January 2nd

(http://www.autoadmit.com/thread.php?thread_id=5604493&forum_id=2\u0026mark_id=5310684",#48150410)