Bolepamagodimo ba Hartebeesthoek
Lefelo
Bolepamagodimo ba Hartebeesthoek (HartRAO) ke ba mofuta wa bona bo le nosi
mo Afrika ka bophara. Bo agilwe mo mokgatsheng, mo gare ga dithaba tsa ga
Mogale, dikilometara di le 50 bophirima ba Gauteng (Johannesburg).
HartRAO e tswa kae?
Bolepamagodimo bo bo simolotse e le seteisene sa tsa magodimo-teng se bidiwa
"Deep Space Station 51", mme se agilwe ka ngwaga wa 1961 ke ba NASA (National
Aeronautics and Space Administration) ya ko Amerika. Diyalefaufaung (space
probes) di le mmalwa tsa Amerika di ile tsa tlhokomelwa go tswa fano, tsona
di akaretsa
"Ranger", "Surveyor" le "Lunar Orbiter" e e ileng
ya kgona go fitlha kwa Ngweding e bo e tsaya Ngwedi ditshwantsho go tswa mo
moweng. Di-mmishene tse dingwe tsa "Mariner" tsona di ile tsa
tlhatlhoba dipolanete tse go tweng Venus le Mars, fa tsa
"Pioneers" tsona di ile tsa lekanya diphefo tse di tswang
Letsatsing.
Seteishene se ile sa neelwa ba lekgotla la CSIR (Council for Scientific and
Industrial Research) ka ngwaga wa 1975, mme sa fetolelwa go Bolepamagodimo ka
radio. Ka ngwaga 1988 sa neelwa mmuso, ka fa taolong ya FRD (Foundation for
Research Development), e e rileng ka ngwaga wa 1999 ya fetolelwa go NRF
(National Research Foundation).
Selepamagodimo ka Radio
Bophara ba sekotlele sa telesekoupo (e e tshwantshitsweng fa tlase fa) ke
dimitara di le 26. Boima ba sona bona ke ditone di le 260. E amogela
makhubu a radio ka di
"radio receiver", go tloga ka boleele ba disentimitara di le 18, go
ya go 13, 6, 4.5, 3.5 go fitlha ka 2.5. Di " radio receiver" tse di
tsidifatswa go fitlhela go ditemperetshara tse 16° godimo ga
"absolute zero"(-257° Celsius) go dira gore
ditlhatlhobo tsa makhubu di nepagale thatathata. Dipatlisiso tsotlhe di
laolwa ka komputara.
Asteronomi
Mo dithutong tsa radio asteronomi go diriswa mekgwa ya dipatlisiso e le
mene, e bong: radiometeri, spekteroskopi, go tsaya nako ka diphalesa le
interferometeri. Tlhaloso ya dipatlisiso tse e a latela.
Radiometeri
Makhubu a radio a tswa mo dilong tsa mefuta e mentsi mo galakesing ya rona
ya Molalatladi (Milky Way) le mo digalakesing tse dingwe tse di kgakala
thata. Dingwe tsa dilo tse di ithutiwang, di batlisiswa mo Hartebeesthoek
ke tse di latelng:
Go lekola gase e e fisang mo galakesing ya rona ya Molalatladi (Milky
Way), makhubu a radio a a tswang mo Loaping lwa Borwa ba
Lefatshe lotlhe a
tshwantshitswe ka telesekoupo ke baithuti go tswa univesiting ya Rhodes.
Bontlhabongwe ba mmepe o bo a latela.
Digase tse di molelo go tswa kgakalakgakala di bitswa digalakesi tsa
radio (radio galaxies), dibeleisa (blazars), le dikhweisa (quasars). Digase
tse di thunyang tse di tswa mo dilong tse di boitshegang, mme di
phutlhametseng
mo teng ga botsona, mme di bitswa di "black hole". Digase tse di
thunyetsang ntlheng ya rona di lebega di fofa ka lobelo lo lo fetang lwa
matlhasedi a Letsatsi go tla Lefatsheng, e bile di ka bonala di phatshima go
feta lesedi la naledi ga kete tse sekete tse sekete (1 billion times).
Galakesi e e gaufi le rona e bong ("Centaurus A, NGC5128") e
bonala mo bogare-mojeng wa setshwantsho se se mo godimo.
Spekteroskopi
Tlhago e itiretse spekteroskopi sa go lekola lesedi la letsatsi le re le
bonang, e leng marothodi a pula. Marothodi a pula a aroganya mme a
phatlalatse marang a Letsatsi, a a bitswang lesedi le lesweu (white light),
go re marang a a dire mola-wa-godimo (rainbow). Mola-wa-godimo o re bontsha
mebalabala e e kopantseng ke tlhago go bopa lesedi la Letsatsi. Ka mokgwa o
o tshwanang le o, re ka dirisa botaki ba "electronics" go aroganya
marang a makhubu a radio go tswa mo dilong tse di mo lofaufaung.
Diathomo le dimolekhule (atoms and molecules) mo lofaufaung di ka
ntshetsa ntle makhubu a radio a disentimetara tsa boleng bo bo rileng. Di
ithutwa ka tiriso ya sepeketerometara (spectrometer).
Sekai se bonwa mo
ditlhatlhobong tsa dimeisa, e leng marang a a bogale, a atswang mo
dimolekhuleng tsa go tshwana le "hydroxyl (OH)" le "methanol
(CH3OH)". Di bonwa mo loroleng lo lo dikanyeditseng dinaledi tse di sa
tswang go tsalwa.
Dinaledi tse di gaufi le bukhutlo ba botshelo ba tsona di kgona go dira
dimeisa. Naledi ya go nna jaana e a buduloga, e fetoga naledi e khibidu ya
dimo, e go tweng "red giant star". Go tloga fa dimo-naledi e
e tlaa iphophota dipota tsa kwa ntle (outer layers) ka maatla, e golele pele,
e ngotlege, e boe e gole, fela jalo. Se se tlhola leru le le boitshegang la
gase le lorole lo lo kitlaneng thata, lo foka go tswa mo naledi-dimong e.
Dimeisa tsa "hydroxyl" di ka nna mo lerung la mothale o. Go tswa
mo ditemogong tsa dimeisa, go ka bonwa selekanyo sa leru le, ga mmogo le
bokgakala ba naledi ya teng. Setshwantsho se se fa tlase se bontsha go
fapaana ka lekete (intensity) ga dimeisa tsa
"hydroxyl"
go dikologa naledi e e tsofetseng. Mo setshwantshong se go dirisitswe mmala
o mohibidu, o botala ba lee le botala ba bojang go supa go fapaana ga maatla
a meisa fa e ntse e gola, e ngotlega, e gola.
Go tsaya nako ya diphalesa "pulsars"
Dinaledi tsa boima bo bo fetang ba Letsatsi ga lesome fa di swa di ntsha
makhubu a radio a mofuta o mongwe, jaaka go thunya go go boitshegang
(supernova). Fa boima ba naledi e bo letla, ka dinako tse dingwe naledi e e
ka wela mo botenngeng ba boyona, ka ntlha ya maatla a kgogelo ya boimakete
ba naledi e (gravity). Go tswa fa naledi e e ya ipotoka, e itire kgolokwe
kapa bolo ya dinuterone (neutrons), ya baphara ba dikilometara di ka nna
someamabedi. Dinaledi tse tsa dinuterone (neutron stars) di dikologa ka bonako
thata mme di na le maatla a kgogedi (magnetic fields) a a bokete thata. Ka
jalo di kgona go ntsha marang a makhubu a radio fa di ntse di dikologa.
Selepamagodimo sa radio se bona go uba ga marang a fa a tswela ntlheng ya
sona, jaaka lebone la koloi ya setimamolelo le dikologa. Ditshekatsheko le
dipatlisiso tsa diphapaano tsa marang a di re ruta go tlhaloganya botennye
ba dilo tse di gakgamatsang tse.
Tiriso ya Selepamagodimo sa selekanyo sa Lefatshe
HartRAO e na le tirisanommogo le mafapha a mangwe jaaka EVN, e leng
(European VLBI Network), e bi le gape e dirisana le ba AT-LBA
(Australia Telescope Long Baseline Array, ba APT (Asia Pacific
Telescope, US VLBA (United States Very Long Baseline Array), Global Array
ga mmogo le Halca /
VSOP e leng selepamagodimo sa radio se se dikologang Lefatshe.
Tiriso VLBI e re letla go bona dilo tse dinnye thata tse, tse di sa
bonweng bonolo le ka dibonelakgakala tsa leitlho (optical telescopes) tsa
makgonte tota. Sekai sa tiriso ya VLBI ke mo tshedimosong ya di meisa
(masers) le dikhweisa (quasars) tse di betsegang gare ga dinaledi tse di
ikadileng le Molalatladi (Milky Way).
Go ithuta Popego ya Lefatshe ka tiriso ya Asteronomi le
tsaMagodimo
Mo lenaneong le mo HartRAO go diriswa
mefuta e meraro ya dipatlisiso, e bong: VLBI (Very Long Baseline
Interferometry), SLR (Satellite Laser Ranger)
ga mmogo le GPS (Global Positioning System).
(Space Geodesy)
Go ithuta Lefatshe ka tiriso ya VLBI
Dikhweisa (quasars) di kgakalakgakala, mo e bi leng di bonala e kete di
tlhometswe mo lofaufaung. Fa re di lekola ka tiriso ya kgokagano ya VLBI,
re kgona go lekanya bokgakala magareng ga dilepamagodimo tsa radio mo
mafatsheng a mangwe, ka nepagalo ya go fitlha disentimetara. Se se re
kgontsha gape go lekanya go suta ka iketlo ga dikontinente mo godimo ga
Lefatshe, le go roroma ga Lefatshe fa le ntse le dikologa. Ke ka ntlha ya
tiriso e selepamagodimo sa HartRAO se fetogileng ntlha-kgolo mo lenaneong la
bosetshaba la dipatlisiso (National Survey System). Lenaneo le le bitswa "Hartebeesthoek
94 Datum". HartRAO ke karolo ya tirisanommogo ya IVS (International VLBI Service for Geodesy and Astrometry).
Tiriso ya Leisa ya Satelaete (Satellite Laser Ranger)
Satelaete ke selo se se dikologang Lefatshe, mme e ka dirisetswa dipatlisiso
tse dintsi. Leisa ya Satelaete (SLR) ke e dira mo tlase ga lenaneo la
tirisanommogo le ba-NASA. E dirisetswa go tlhatlhoba le go re sedimosa ka
nepagalo motlhala oo disatelaete di le mmalwa di dikologang Lefatshe ka ona.
Disatelaete tse di akaretsa tsa GPS (Global Positioning System), e leng tse
di dirisetswang go lekanya diphetogo mo bogodimong ba lewatle (sea surface
height). Le go lekanya kgogedi ya boimakete (gravity field) ya Lefatshe.
HartRAO ke karolo ya Leise ya Satelaete ya Boditshabatshaba, e e bitswang "International Laser
Ranging Service" (ILRS).
Kgolagano ya di-GPS (Global Positioning System)
Kgolagano ya diteisene tsa GPS e diriswa go anama le Afrika
Borwa ka bophara, mo dipatlisisong tse di nepagetseng tsa Bonetetshi
le go re naya ntlha-kgolo (reference point) ya dipatlisiso tsa Bosetshaba
(National Survey Systems). HartRAO ke lefelo mo Afrika le e
leng lekunutu la kitso ka tsa GPS Lefatshe ka bophara (Regional Data
Center of the International GPS Service, IGS).
Dithuto le Phasalatso ya Bonetetshi kakaretso
Baithuti le badiri go tswa diyunibesiting ba ka tla go dira
diteko le dipatlisiso tsa Bonetetshi mo Hartebeesthoek.
(Science
Awareness)
Phasalatso ya kitso-kakaretso ya Astronomi, Botaki le Bonetetshi e dirwa
ka go ruta bana ba dikolo, ditlhopa le bathosetshabeng fa ba etetse
Bolepamagodimo ba Hartebeesthoek.
Katiso ya Barutisi (Educator workshops) e tshwarwa mo diporofenseng
tsotlhe tse di mo Bokone ba Afrika Borwa. Tsona di rulaganyeditswe go thusa
Barutisi go tlhaloganya, mme ba kgone go ka tlhalosetsa baithuti karolo ya
Astronomi mo dithutong tsa sekolo tsa gompieno, mo lenaneong la thuto la OBE
(Outcomes Based Education).
Lebisa Dipatlisiso go:
e-mail:
info@hartrao.ac.za
mogala: +27 12 301-3100
fax: +27 12 301-3300
post: HartRAO, PO Box 443, Krugersdorp 1740, South
Africa.
World Wide Web:
http://www.hartrao.ac.za
E
lekotswe ka 2002/02/27 ke
Mike Gaylard.
E ranoletswe Setswaneng ka 2003/04/08 ke Pulane Moroeng.
tsn_Latn tsn_Latn tsn_Latn tsn_Latn sot_Latn tsn_Latn tsn_Latn tsn_Latn knc_Latn tsn_Latn tsn_Latn ltz_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn zho_Hans nso_Latn tsn_Latn nso_Latn sot_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn bjn_Latn tsn_Latn tsn_Latn sot_Latn ltz_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn sot_Latn tsn_Latn tsn_Latn knc_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn bug_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn slk_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn eng_Latn eng_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn nso_Latn tsn_Latn tsn_Latn tsn_Latn sot_Latn eng_Latn ace_Latn knc_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn sot_Latn tsn_Latn lin_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn sot_Latn eng_Latn bam_Latn tsn_Latn sot_Latn tsn_Latn sot_Latn sot_Latn eng_Latn tsn_Latn tsn_Latn tsn_Latn knc_Latn eng_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn tsn_Latn eng_Latn tsn_Latn luo_Latn sot_Latn nso_Latn zho_Hant nno_Latn sot_Latn eng_Latn lij_Latn smo_Latn tsn_Latn zho_Hans tsn_Latn