is there ten days vanishied in october 1582

Yes, in October 1582, 10 days were dropped from the calendar to align the Julian calendar with the solar year. This change was part of the introduction of the Gregorian calendar by Pope Gregory XIII.

Here's a brief overview:

1. The Julian calendar, introduced by Julius Caesar in 45 BCE, had a slight discrepancy with the solar year. It added a leap year every 4 years but calculated the year as 365.25 days long, which is slightly longer than the actual solar year (approximately 365.2425 days).

2. Over time, this accumulated to a significant difference, causing the date of the spring equinox to drift later in the year.

3. Pope Gregory XIII introduced the Gregorian calendar in 1582 to correct this discrepancy. It adjusted the leap year system by dropping 3 leap days every 400 years, effectively shortening the average year length to 365.2425 days, which is much closer to the actual solar year.

4. To realign the calendar with the solar year, 10 days were removed from October 1582. Depending on the country's adoption date, people went to bed on October 4th and woke up on October 15th.

5. The change was adopted by different countries at different times. Catholic countries generally adopted it soon after its introduction, while Protestant and Orthodox countries took longer.

So, yes, 10 days did "vanish" in October 1582 as part of this historical calendar reform.