Seigo­nie Mo­hammed

Cli­mate Change Ed­i­tor

seigo­nie.mo­hammed

@guardian.co.tt

Sky­watch­ers across Trinidad and To­ba­go may want to stay up a lit­tle lat­er tonight, as one of the year’s more im­pres­sive ce­les­tial shows un­folds di­rect­ly over­head.

A deep par­tial lu­nar eclipse will be vis­i­ble across the coun­try overnight, tonight in­to to­mor­row, with al­most the en­tire Moon slip­ping in­to the dark­est part of Earth’s shad­ow.

And un­like a so­lar eclipse, there is no need for spe­cial glass­es; just look up.

The eclipse be­gins at 9.23 pm to­day, when the Moon starts en­ter­ing the lighter out­er por­tion of Earth’s shad­ow, known as the penum­bra. At first, the change may be dif­fi­cult to no­tice.

The re­al show be­gins at about 10.33 pm, when the par­tial eclipse gets un­der­way, and Earth’s much dark­er um­bral shad­ow be­gins mov­ing across the Moon.

From T&T, it should ap­pear as though a dark “bite” is slow­ly be­ing tak­en out of the lu­nar sur­face.

The eclipse reach­es its max­i­mum at ap­prox­i­mate­ly 12.12 am to­mor­row (Fri­day), when the Moon will be high in the south­ern sky.

The event will come tan­ta­lis­ing­ly close to a to­tal lu­nar eclipse, but a small por­tion of the Moon will re­main out­side Earth’s dark­est shad­ow.

That could make for an es­pe­cial­ly strik­ing sight.

As more of the Moon en­ters Earth’s shad­ow, ob­servers may no­tice the eclipsed por­tion tak­ing on shades of red, cop­per or or­ange, while a small sec­tion re­mains much brighter.

The red­dish colour is caused by sun­light fil­ter­ing through Earth’s at­mos­phere be­fore reach­ing the Moon. Short­er wave­lengths of light are scat­tered more read­i­ly, while more of the red and or­ange wave­lengths make their way through the at­mos­phere and on­to the lu­nar sur­face; the same ba­sic phe­nom­e­non that helps pro­duce colour­ful sun­ris­es and sun­sets.

The deep­er the eclipse be­comes, the more no­tice­able that colour could be, al­though ex­act­ly what peo­ple see will de­pend heav­i­ly on cloud cov­er, haze and oth­er at­mos­pher­ic con­di­tions.

No tele­scope re­quired

One of the ad­van­tages of a lu­nar eclipse is its sim­plic­i­ty.

There are no spe­cial view­ing pre­cau­tions re­quired, and it is com­plete­ly safe to watch with the naked eye.

Binoc­u­lars or a tele­scope can pro­vide a clos­er look, but they are not nec­es­sary.

For the best ex­pe­ri­ence, find some­where with a rea­son­ably clear view of the sky and, if pos­si­ble, away from bright street­lights and oth­er sources of light pol­lu­tion.

Af­ter a max­i­mum eclipse, the process will slow­ly re­verse. The par­tial phase ends at ap­prox­i­mate­ly 1.51 am, with the fi­nal, much sub­tler penum­bral phase end­ing around 3.01 am.

That gives T&T a view of the eclipse from be­gin­ning to end, last­ing about five hours and 38 min­utes.

And we will have plen­ty of com­pa­ny.

The eclipse will al­so be vis­i­ble from much of the Amer­i­c­as, Africa and Eu­rope, along with parts of Green­land, Antarc­ti­ca and the east­ern Pa­cif­ic.

Lu­nar eclipses oc­cur si­mul­ta­ne­ous­ly around the world, but can on­ly be seen from places where the Moon is above the hori­zon at the time.

So, weath­er per­mit­ting, tonight re­quires very lit­tle prepa­ra­tion: find a com­fort­able spot, give your eyes some time to ad­just to the dark­ness and look to­wards the Moon. The uni­verse will han­dle the rest.