Gravity anobatsira: yemahara slingshot

Mu 1977, Voyager zvikepe zvepasi zvakasiya nyika panzira iyo inoshandisa yakaoma kutevedzera kweJupiter, Saturn, Uranus uye Neptune, izvo zvinoitika kamwe chete pamakore 175 kana kuti zvichienzaniswa. Nekuti pakanga pasina mvura, nyika dzaifamba nesimba. Pasina izvi, Voyager 2 haizove yasvika kuNeptune mumakore makumi maviri nemana.

Iyo mvura haisi kuburitsa simba. Inogona kukupa kutenderera kwayo.

Ona

Kufananidza tennis mutambo akaiswa pashure pechitima ichifamba. Ichibva yadzokerazve nekukurumidza kupfuura yakanga yakasviba, nekuti chitima chainge chiri kuenderera mberi. A gravity kubatsirwa ndeimwe yakafanana pfungwa, ne gravity sezviri nyore:

1. Kubva paplaneti, chikepe chepasi chinobuda, chinofamba uye chinokwira kunze neyakaenzana nesimba racho. Asi nzira ichange ichichinja.
2. Kubva kuzuva, nyika inogara ichifamba nechiyero chemakiromita makumi maviri pasekondi. Idzi shanduko dzinogona kuitwa nechikepe chepasi pezuva, kana kuti spacecraft, mushure mekubuda mumhepo: nekuti nzira yacho yakachinja, iyo yese inofamba inogona kunge iri yakakura kupfuura panguva iyoyo.

Kufamba kumberi kweplaneti, munzira yeplaneti, kunowedzera kumhanya. Kufamba pashure kunotora nguva; ichi ndicho chikonzero nei Messenger yakanga yanonoka kusvika kuMercury.

_Zvinyorwa

Mumuenzaniso, chikepe chepasi chinosvika kuJupiter pa v∞ = 7.5 km/s uye chinoenda 5 Jupiter radii kubva kumashure. The hyperbola bends yake nzira ne

δ = 2 arcsin(1/e),   e = 1 + r_p v∞² / μ

Ne μ_Jupiter = 1.267 × 10⁸ km³/s², e = 1.16 uye kutenderera kuri pamusoro pe 119 degrees. Kuwedzera kweJupiter’s orbital velocity (13.1 km/s):

• Pashure: 7.6 km/s Kuenzanisa nezuva.
• After: about 19.9 km/s Kuenzanisa nezuva.

Iyo spacecraft yakawana kupfuura 12 km / s pasina kudzima injini. Jupiter, 10²⁴ times heavier, lost the same momentum and slowed by an amount far too small ever to measure.

Munyori

Iyo yakakura kwazvo inogona kuchinja kweheliocentric speed ndeye 2 v∞ sin(δ/2), inosvika kana iyo inotyisa uye inobuda ine simba rakaenzana pamusoro pesimba replaneti. Sezvo mvura iri kubuda mumhepo ichienda kumativi ose epasi, uye sezvinoita mabhakitiriya, zvinoda nguva yakareba kuti zviite basa ravo.

Gravity aids ndeyekufambisa kweorbital energy mu three-body problem: mune yeplanet’s frame energy inogara; muSun’s frame spacecraft’s energy changes by Δ = v_planet · Δv_rel. Vagadziri vemisiyano vanozvibatanidza (Cassini: Venus, Venus, Earth, Jupiter) uye vawedzera madiki powered flybys uko kupisa panzvimbo yakatarisana neOberth effect.