Te Kapua Oort me te Pūtake o ngā Ākote
Ina titiro tātou ki te rangi pō, he maha ngā wā ka puta mai ngā whetu komete hei "manuhiri" whakamīharo - he kanapa me ngā hiku roa, e puta mai ana i te pōuri, ā, ka ngaro anō mō ngā tekau, ngā mano, tae noa ki ngā miriona tau. Engari ko te pātai nui: nō hea mai ngā whetu komete? Ko tētahi o ngā whakautu nui i roto i te ao whetū o ēnei rā ko te Kapua Oort, he rohe whakapae kei waho o te Pūnaha Rā e whakaarohia ana he "pūranga" roa mō ngā whetu komete. Ka tūhuratia e tēnei tuhinga he aha te Kapua Oort, me pēhea te hanganga, me te take he mea nui kia mārama ki ngā takenga mai o ngā whetu komete.
He aha te Kapua Oort?
Ko te Kapua Oort he kohinga o ngā mea ririki kei roto te hukapapa, te puehu, me te toka e whakaarohia ana kei te porowhita i te Pūnaha Rā i tawhiti rawa atu i te Rā. Kāore anō kia kitea tika tēnei rohe mā te karu tiro, engari ko tōna noho mai i ngā tauira porowhita o ngā whetu whetu e kitea ana e tātou.
I te nuinga o te wā, e whakaarohia ana he rite te āhua o te Kapua Oort ki tētahi porowhita nui (he "kōpaki" porowhita rānei) e karapoti ana i te Pūnaha Rā. He mea whakamiharo tōna tawhiti: ko ōna tawhiti o roto rawa ka tīmata pea i te 2.000 wae whetū (AU) mai i te Rā, ko tōna tawhiti o waho rawa ka toro atu ki te 50.000–100.000 AU. Hei whakataurite, ko te 1 AU te tawhiti toharite mai i te Ao ki te Rā. Ko te tikanga o tēnei ko ngā rohe o waho rawa o te Kapua Oort ka tata pea ki te awe o te kaha ā-papa o te Rā, ā, ka taunekeneke ki te taiao o waenga-whetu.
He aha i huaina ai ko "Ōort"?
I tapaina te Kapua Oort i muri i te tohunga whetū Tatimana a Jan Oort, nāna i whakaaro i te tau 1950 ko ngā whetu whetū roa-wā e ahu mai ana i tētahi "pūngao" tawhiti. I tātarihia e ia te tohatoha o ngā porowhita whetu, ā, i kitea e ia he maha ngā whetu whetū e ahu mai ana i ngā ahunga matapōkere o te rangi, kāore i te herea ki te papa ecliptic (te papa e porowhita ai ngā aorangi). He uaua tēnei ki te whakamārama mēnā i ahu mai i tētahi kōpae papatahi anake. Nō reira, i hiahiatia he pūtake "porowhita" ake—pērā i te kapua porowhita.
Ngā Kōmete: Ngā Manuhiri mai i te Pito o te Pūnaha Rā
He whakarāpopototanga noa iho, he mea iti te kōmeta i hangaia mai i te ranunga o te hukapapa (wai, hauhā waro, methane, haukini), puehu, me ngā rauemi rauropi. Ina whakatata atu te kōmeta ki te Rā, ka meinga e te wera te hukapapa kia mimiti, ka hanga he kōma (he anga hau me te puehu) me te hiku. Nā tēnei āhuatanga i tino whakamiharo ai ngā kōmeta.
E rua ngā wāhanga whānui o ngā kōmete:
1. Ngā whetu kōmete wā-poto, me ngā wā porowhita iti iho i te 200 tau. He maha o ēnei i ahu mai i te Whitiki Kuiper, i te rohe kōpae marara rānei i tua atu o Neptune.
2. Ngā wheturangi roa-wā, me ngā wā hurihuri neke atu i te 200 tau, ā, ka tae pea ki ngā tekau mano tau. Ko tēnei rōpū te mea tino hono atu ki te Kapua Oort.
He porowhita porowhita rawa ngā porowhita roa-wā o ngā whetu whetu, ā, ka puta mai i ngā taha katoa, me te mea nei ka "taka" ki roto i te Pūnaha Rā o roto. E tautoko ana tēnei tauira i te ariā ko tō rātou pūtake he kapua porowhita e karapoti ana i a tātou mai i tawhiti.
Me pēhea te hanganga o te Kapua Oort?
Hei mārama ki te Kapua Oort, me hoki tātou ki ngā rā tōmua o te Pūnaha Rā, tata ki te 4,6 piriona tau ki muri. I hangaia te Rā me ngā aorangi mai i tētahi kōpae hau me te puehu e kiia nei ko te nebula proto-solar. I ngā rohe o waho, he tino makariri ngā pāmahana, ā, ka ngāwari te hanga o te hukapapa. He maha ngā tinana iti, hukapapa—ngā tūāpapa o ngā kōmete—i hangaia i te rohe o ngā aorangi nunui (Hūpiter, Saturn, Uranus, me Neptune).
Heoi, kāore i te pumau tonu ngā porowhita o ēnei mea ririki. I te tipu haere me te hekenga o ngā aorangi nunui, ka huri tō rātou kaha ā-papa hei "mīhini maka" tino whai hua. He maha ngā mea ririki ka panaia ki roto i:
– ngā porowhita e tukinga ana ki te Rā, ki ngā aorangi rānei,
– ngā porowhita e toe ana ki ngā rohe o waho (hei tauira, te Whitiki Kuiper),
– me te mea he tawhiti rawa te tawhiti o te ao hurihuri, ā, ka "tū" ki waho o te Pūnaha Rā.
Koinei te wāhi e whai wāhi nui ai te taiao o te ao tūroa. Ka pāngia ngā mea e whiua ana ki tawhiti e ngā raruraru ā-papa o ngā whetū e haere ana me te tōnga tai o ngā tupuni. Ka taea e ēnei raruraru te huri i ō rātou porowhita mai i te porowhita porowhita i te papa kotahi ki ngā porowhita marara matapōkere i ngā taha katoa—ka hangaia he hanganga porowhita: te Kapua Oort.
I roto i te poto, e whakaarohia ana i hangaia te Kapua Oort mai i ngā mea momona i te hukapapa i tata ki te rohe o ngā aorangi nunui, kātahi ka makahia e te kaha o aua aorangi, ā, ka "whakaū" i tawhiti nā te awe o te taiao o te aorangi.
He aha te mea e tuku ana i ngā whetu whetu mai i te kapua o Oort ki te taha o te rā?
Mena he putunga mō ngā whetu komete te Kapua Oort, he aha rātou i "mawhiti" ai, ka tomo ki roto i te Pūnaha Rā o roto? Kei roto i ngā raruraru iti engari pumau te whakautu, tae atu ki:
1. Ngā tai o te ao tūroa: E porowhita ana te Pūnaha Rā i waenganui o te Ara Milky. Ka taea e te papa tō o te ao tūroa te kukume i ngā mea i roto i te Kapua Oort, engari he nui hei whakarerekē i ō rātou porowhita.
2. Ngā whetū e haere ana: I ētahi wā, ka tata te haere a tētahi atu whetū i runga i te tirohanga whetū. Ahakoa kei tawhiti tonu, ka taea e tōna kaha ā-papa te "ruru" i te Kapua Oort.
3. Ngā kapua ngota nunui: Ka taea hoki e ngā hanganga hau nunui i roto i ngā tupua whetu te whakaputa i ngā raruraru ā-papa ina pā tata atu te Pūnaha Rā.
Nā tēnei whakararuraru, ka panaia ētahi mea ki roto i ngā porowhita ka taka ki roto i te rohe o roto, ka noho hei ngā kōmete wā roa ka taea e tātou te mātakitaki. He maha ka panaia katoatia ki waho ka huri hei mea i waenga i ngā whetu.
Ngā Taunakitanga Ārai mō te Nohoanga o te Kapua Oort
Nā te tawhiti nui me te iti, te ngoikore o ngā mea, he uaua ki te tirotiro tika i te Kapua Oort. Heoi, he maha ngā tohu kaha e tautoko ana i tōna noho:
– He matapōkere te ahunga taenga mai o ngā wheturangi roa, ā, kāore e herea ki te papa kotahi.
– Ko te tohatoha pūngao porowhita o ngā whetu komete e tohu ana i te noho mai o tētahi taupori pūtake tawhiti.
– Mā ngā tauira hanganga o te Pūnaha Rā e whakamahi ana i ngā aorangi nunui ka puta he taupori o ngā mea ka whiua ki tawhiti rawa.
Heoi anō, kei te tautohetia tonutia ngā taipitopito: he aha te taumaha katoa o te Kapua Oort, he aha ōna hanganga o roto, o waho hoki, me te auau o te tukuna o ngā kōmete ki roto i te Pūnaha Rā o roto.
Te Hononga o te Kapua Oort ki ngā Pūtake o te Wai me te Ora
He maha ngā wā ka kiia ngā kōmete he "kāpū wā" mai i te Pūnaha Rā o mua. Kāore i te tino rerekē ngā rauemi o roto, ā, ka taea e rātou te tiaki i ngā mōhiohio matū tawhito. Kua whakapaetia pea i whai wāhi ngā kōmete ki ētahi o ngā ngota wai me ngā ngota rauropi o te Ao. Heoi, ko ngā inenga o ngā isotopes hauwai (te ōwehenga o te deuterium ki te hauwai) i roto i ētahi kōmete e tohu ana kāore ngā kōmete katoa e hototahi ki te wai moana o te Ao. Ko te tikanga o tēnei kei te tautohetohe tonuhia te takoha a ngā kōmete ki te wai o te Ao, ā, tera pea he mahi nui tā ngā asteroids whai wai. Ahakoa rā, he mea nui tonu ngā kōmete—tae atu ki ērā mai i te Kapua Oort—hei māramatanga ki te tohatoha o ngā mea rerehua me ngā mea rauropi i roto i te Pūnaha Rā taitamariki.
Te Anamata o te Rangahau Kapua o Oort
Mā ngā whanaketanga o ngā karu tiro rangi, pērā i te Vera C. Rubin Observatory (LSST), ka pai ake tō tātou kaha ki te kite i ngā whetu hou me te mahere i ō rātou tatauranga āmiomio. Mā te maha atu o ngā whetu roa e kitea, ka pai ake te whakamātautau i ngā tauira o te Kapua Oort: te matotoru o te ao, te horapa o ōna āmiomio, me te hiranga o te mahi a ngā raruraru o te ao whetu me ngā ara o ngā whetu.
Ā tōna wā, ka taea hoki te kite i ngā mea tino nui o te ao whakawhiti-Neptunian, ā, ko ō rātou ara ia e tohu ana i te awe o te Kapua Oort o roto. Ahakoa kei tawhiti tonu i te toro atu a ngā waka mokowhiti, ko te Kapua Oort tētahi o ngā rohe tino whakamīharo i roto i te rangahau o te Pūnaha Rā: he rohe e hono ana i te āputa i waenga i te ao aorangi me te wāhi i waenga i ngā whetu.
Te Katinga
Ko te Kapua Oort tētahi ariā matua e āwhina ana i a tātou ki te whakamārama i ngā takenga mai o ngā kōmete wā roa—he kōmete e ahu mai ana i ngā aorangi tino tawhiti, ā, e whai ana i ngā porowhita matapōkere, tino porowhita. Ahakoa kāore anō kia kitea tika, ko ngā taunakitanga mai i ngā whanaketanga porowhita kōmete me ngā tauira o te hanganga o te Pūnaha Rā e tautoko ana i tōna noho hei puna hukapapa taketake i te taha o te awe o te Rā. Ko te mārama ki te Kapua Oort ko te mārama ki te hītori o te Pūnaha Rā, ngā tikanga ā-papa i hanga i a ia, me te kaha o ngā kōmete ki te pupuri i ngā tohu matū mō ngā aorangi o mua—tae atu ki a Papatūānuku.
Ki te hiahia koe, ka taea e au te whakarerekē i tēnei tuhinga ki tētahi momo tuhinga rongonui ake mā ngā ākonga, ki tētahi momo tuhinga mātauranga ake rānei me ngā tohutoro me ngā puna pānui.
