What to expect from each stage of the partial solar eclipse on Sept. 21

On Sept. 21-22, a partial solar eclipse will see the moon sweep over the sun's disk, blocking its light over a swathe of the southern hemisphere! Here's what you can expect as the solar system alignment unfolds.

A partial solar eclipse takes place when the moon's orbit places the natural satellite directly between the Earth and sun during its monthly new moon phase, blocking our view of a portion — but not the totality of — the sun's disk.

The Sept. 21-22 partial solar eclipse will be visible to over 16 million people observing from a number of Pacific islands, along with parts of Australia and Antarctica, according to Time and Date. The rest of the world will be able to follow along via Time and Date's livestream, which will be hosted on Space.com, providing live views and expert commentary on the event as it unfolds

Stage 1: First contact (partial begins)

Stargazers will get their first glimpse of the eclipse shortly after its global start at 1:29 p.m. EDT (1729 GMT) on Sept. 21, when the curved silhouette of Earth's satellite will begin to graze the upper right region of the solar disk for viewers in the island country of Samoa.

Stage 2: Deepening partial

The hours that follow will see the path of the eclipse sweep over a vast region of the Pacific Ocean encompassing New Zealand, Fiji and a host of smaller islands. All the while, the moon's silhouette will sink further into the disk of our parent star, transforming its usually perfect sphere into a radiant crescent.

Stage 3: Maximum eclipse

At 3:41 p.m. EDT (1941 GMT), the eclipse will reach its maximum over a largely uninhabited patch of Pacific Ocean, when most of the sun's disk will be hidden by the moon.. As the eclipse reaches its maximum for your location, points of light shining through small gaps, such as the holes of a colander or spaces between leaves, may appear as tiny crescents, echoing the scene in the sky.

New Zealand and Antarctica will witness some of the most spectacular views of the eclipse in the hour surrounding the maximum, with over 70% of the sun's disk covered by the moon's silhouette, forcing it to take on the appearance of an upturned sickle.

Stage 4: Waning partial

Over the next few hours, the moon will appear to roll from left to right off the solar disk for viewers in New Zealand, while the final glimpse of the eclipse will be visible from an isolated peninsula of the Antarctic at 5:53 p.m. ET (2153 GMT), assuming there are any humans — or penguins — there to see it.

How to view the eclipse

Because the Sept. 21 event is a partial eclipse, it is NEVER safe to observe it with the naked eye — even from locations where most of the sun's disk is covered at maximum.

Be sure to check out our guide to safely viewing the sun, along with our explainer on where to buy quality eclipse glasses and how to check that your gear is in good working order.

Editor's Note: If you capture an image of the partial solar eclipse and want to share it with Space.com's readers, then please send your photo(s), comments, and your name and location to spacephotos@space.com.