On the night of 27th to 28th September there is a total supermoon lunar eclipse, supermoon because the moon is nearest it's closest to the Earth (perigee) in the monthly cycle of movement of the moon moving closer to and further away from the Earth. This means the moon appears particularly large.
There is more about when you can see it here:
http://www.space.com/30607-supermoon-lunar-eclipse-time-place-guide.html
About a 'blood moon'
The full moon nearly always appears coppery red during a total lunar eclipse. Although it sounds dramatic, the term blood moon can be applied to any and all total lunar eclipses.
During a lunar eclipse, you’ll see the Earth’s shadow creeping across the moon’s face. The shadow will appear dark, like a bite taken out of a cookie, until the shadow completely covers the moon. Then, during the breathtaking time of totality, the shadow on the moon’s face often suddenly changes. Instead of dark, it appears red. Why?
During a total lunar eclipse, the Earth lies directly between the sun and the moon, causing the Earth to cast its shadow on the moon. If Earth didn’t have an atmosphere, then, when the moon was entirely within Earth’s shadow, the moon would would appear black, perhaps even invisible.
Thanks to Earth’s atmosphere, what actually happens is much more subtle and beautiful.
Earth’s atmosphere extends about 50 miles (80 kilometers) above Earth’s surface. During a total lunar eclipse, when the moon is submerged in Earth’s shadow, there is circular ring around Earth – the ring of our atmosphere – through which the sun’s rays pass.
Sunlight is composed of a range of frequencies. As sunlight passes through our atmosphere, the green to violet portion of the light spectrum is, essentially, filtered out. This same effect, by the way, is what makes our sky blue during the day. Meanwhile, the reddish portion of the spectrum is least affected.
What’s more, when this reddish light first entered the atmosphere, it was bent (refracted) toward the Earth’s surface. It’s bent again when it exits on the other side of Earth. This double bending sends the reddish light onto the moon during a total lunar eclipse.
http://earthsky.org/space/why-does-the-moon-look-red-during-a-total-lunar-eclipse
About a harvest moon
In traditional skylore, the Harvest Moon is the full moon closest to the autumnal equinox, and depending on the year, the Harvest Moon can come anywhere from two weeks before to two weeks after the autumnal equinox. For us in the Northern Hemisphere, the 2015 autumnal equinox comes on September 23, so the September 27-28 full moon counts as the Northern Hemisphere’s Harvest Moon.
By the way, this year’s Harvest Moon will present the closest and largest full moon of the year. It’ll also stage a total eclipse of the moon on the night of September 27-28.
However, the Harvest Moon isn’t always the biggest full moon of the year or more pumpkin-colored than other full moons. It’s special because, at this time of year in the Northern Hemisphere, the time between successive moonrises – from one night to the next – is shorter than usual. But this year, 2015, the Harvest Moon is a bit bigger than usual … because it’s a supermoon.
This year’s Harvest Moon qualifies as a supermoon because the moon turns full about one hour after reaching lunar perigee – the moon’s closest point to Earth for the month. Read more about the 2015 supermoons here.
Will you notice the extra-large size of this full September Harvest Moon using just your eye?
http://earthsky.org/space/harvest-moon-2#what
More about the supermoon eclipse here:
http://www.timeanddate.com/eclipse/facts-lunar-eclipse.html
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