Today I'be writing about an under-appreciated weather phenomenon we all see if not daily – than most of the days. It's just that people often don't pay attention to details or perhaps they do notice it but have no idea that it has a name or that it even classifies as a weather phenomena. We are used to seeing and Instagramming glorious sunsets and sunrises, however, on the opposite horizon to the Sun is a little-known atmospheric phenomenon. Named after the Roman goddess of love we all know as Venus, a pink to brownish border separating the dark shadow band of the earth from the sky above it appears. It extends about 10-20 degrees up from the horizon, acting as a boundary between the shadow and the sky. In both the evening and morning sky, try watching for Earth's shadow. Earth's shadow is a deep blue-grey, darker than the twilight sky. The pink band above the shadow – in the east after sunset, or west before dawn – is called the Belt of Venus. Earth's shadow can be seen any clear evening ascending in the eastern sky at the same rate that the sun sets below the western horizon. Basically, what you are seeing is the shadow of the Earth’s translucent atmosphere, casting a shadow back upon itself. The shadow of the Earth is big. You might have to turn your head to see the whole thing. And the shadow is curved, in just the same way that the whole Earth is curved. Earth's shadow extends hundreds of thousands of miles into space – so far that it can touch the moon. Whenever that happens, there's an eclipse of the moon. Having that in mind, belt of Venus us a perfect opportunity to see a part of the Earth's shadow other than during a lunar eclipse. It is best visible when the atmosphere is cloudless, yet very dusty, just after sunset. This beautiful pinkish glow is caused by the backscattering of sunlight and is sometimes referred to as the anti-twilight arch. I wil be the first to correct my mistake of not taking more pictures of Belt of Venus. Hopefully I'll post more on my Instagram profile. If you do the same, don't forget to tag me so if we make enough photos together to make a pretty collage – I'll publish it on the blog! What do you say, are you in?
Danas pisem o relativno potcijenjenom meteoroloskom fenomenu koji zasigurno vidjamo, ako ne svaki dan, onda vecinu vremena. Jednostavno je stvar u tome da ljudi ili naprosto ne obracaju paznju na pojedine detalje ili ih primjete no ne znaju im naziv niti da se uopste radi o vremenskom fenomenu. Vecinu vremena primjecujemo i preko Instagrama dijelimo fotke zalazaka i izlazaka sunca koji oduzimaju dah. Ipak, nasuprot horizontu i tik uz rame suncu nam namiguje jedna jako lijepa pojava. Nazvana po rimskoj bozici ljubavi itekako poznatoj svima kao Venera, ruzicasto-smedjkasta izmaglica razdvaja povrsinu zemlje od neba koje pluta nad njom. Ta romanticna izmaglica se prostire 10-20 stepeni iznad horizonta, ponasajuci se kao granica postavljena izmedju sjene i neba. U oba slucaja (rano ujutro u svitanje i predvecer u suton), pokusajte osmotriti sjenu koju pravi planeta Zemlja. Sjena nase planete je duboke plavicasto-sive boje, tamnije od nijansi sutona. Ruzicasta traka iznad Zemljine sjene – istocno nakon zalaska sunca a zapadno prije svitanja – zove se Venerin pojas. Sjena planete Zemlje se moze uociti svake noci pred zalazak sunca dok je nebo cisto i bistro, jednako kao i ujutro prije svitanja. U sustini, radi se o tome da vidite Zemljinu transparentnu atmosferu koja ‘baca’ vlastitu sjenu na sebe. Ta sjena je velika i morati cete se mozda i okrenuti puni krug oko sebe da bi je vidjeli cijelu. Takodjer, ta sjena je zakrivljena bas kao sto je silueta planete zakrivljena. Zemljina sjena se prostire stotine hiljada milja u svemiru – toliko daleko da dotice Mjesec. Kada god sjena planete Zemlje pomiluje Mjesec, desava se ono sto poznajemo kao pomrcina Mjeseca. Samim time, Venerin pojas je idealna prilika da pogledamo djelic Zemljine sjene bez da cekamo tu pomrcinu Mjeseca. Najbolje i najjasnije je vidljiva kada je atmosfera cista od oblaka no blago zamucena – upravo kao nakon zalaska Sunca. Ta krasna, romanticna ruzicasta izmaglica je uzrokovana povratnom difuzijom (povratnim rasipanjem) sunceve svjetlosti. Prva cu da ispravim nepravedno zapostavljen Venerin pojas i pokusati cu cesce da ga ‘uhvatim’ na fotkama koje cu objaviti na svom Instagram profilu. Ukoliko i vi to isto budete zeljele i ako budete imale par fotki, mozemo zajedno da napravimo lijep kolaz Venerinog pojasa. Ja bih voljela da to zajedno uradimo i kolaz cu objaviti na blogu! Sta kazete, da li ste zainteresovane? (drzim fige da jeste!)
