Large plume of smoke from the Alamo Fire in southern California, blowing over the eastern Pacific on July 9. Areas burning actively at that time appear in red.

Look inside the bright primary bow for colorful fringes, whose number and spacing can change from minute to minute. Alexander Krivenyshev caught this one over New York City on Saturday, July 8.

Experts say there's a 60% chance this weekend of geomagnetic storms, possibly causing auroras. Plus, over the past couple of days, a lone sunspot has grown rapidly!

Wonderful video showing noctilucent - or night-shining - clouds recorded on July 1 and 4. These clouds shine in the darkness, typically on summer nights.

Would climate change stop? The simple answer is no. A climate scientist explains.

The 5.8-magnitude earthquake in western Montana took place just after midnight, local time. It woke people up near the epicenter and was felt throughout the region. Expect aftershocks.

Across the US Southwest - amid a record-breaking heat wave - fires that started in early June continue to burn.

Good news for coral reefs at last! After 3 years, the global coral bleaching event is likely over, scientists say.

Ongoing drought - and increasing temperatures - have reduced water flow in the Colorado River, with more dramatic reductions expected. This ongoing, unprecedented event threatens water supplies in cities in the U.S. West and some of the most productive agricultural lands anywhere in the world.

The ice sheets are melting from both above and below, say scientists.