* Astronomy

The Saudi Geological Survey (SGS) has ruled out the possibility of any volcanic or seismic activity in the Kingdom during the next two years, refuting predictions made by the US Geological Survey (USGS).
Professor Ali Adnan Eshky of King Abdulaziz University in Jeddah warned of possible volcanic eruptions in the Kingdom during the next two years, citing the USGS report. He said a volcano in Al-Eis would affect Madinah, Yanbu and surrounding areas.
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List of volcanoes in Saudi Arabia

Citizens, pilgrims and visiting traders in Madinah all felt them. The new moon had announced the start of Jumada al-Akhira, the sixth month of the year 654 of the Muslim, or hijri, calendar - ad 1256 of the Gregorian calendar. Over the next four days, the tremors became more frequent and more intense. On the morning of the fifth day, a Friday, at least 18 shocks occurred, and as people prepared for midday congregational prayers at the Prophets Mosque, a strong earthquake rocked Madinah, spreading alarm throughout the city and in outlying villages.
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