Pusan Nation Uni l 부대신문 l PUBS
편집 : 2019.3.20 수 12:13 About Us · Notice · Free Board · Link
> 뉴스 > Feature Story > Science Story
Who Are You, the Naro?
276th Science Story
2009년 12월 18일 (금) 18:35:53 Lee Shin-ae lsa@pusan.ac.kr

Who Are You, the Naro?

Ed- On August 25th at 5 P.M, the Naro, Korea Space Launch Vehicle-I (KSLV-I) was launched from the Naro space center. Its mission was to put the Science and Technology Satellite-2 (STSAT-2) into *target orbit. The STSAT-2 separated from the KSLV-I as planned but failed to reach the intended position due to the problems of the fairing.
*target orbit: an elliptical orbit of 300 km which the Naro was supposed to put into. Orbit of 300km ? 1500km is called Low Earth Orbit(LEO).

The first-stage fuel rocket was seperated from the KSLV-1

What fueled the Naro?
    The Naro succeeded in launching and reached a particular orbit which means the engine worked successfully. The engine rocket of the Naro was divided into two parts. The first-stage rocket used liquid fuel and the second-stage rocket used solid fuel. The first-stage rocket gave power to move the vehicle into the atmosphere. After the vehicle reached a particular altitude, the first-stage rocket was separated from the rocket body, which made the rocket lighter. After that, the second-stage rocket, a kick motor powered the lightened rocket to reach target orbit.

This picture depicts and ideal separation of the faring , which the Naro failed to achieve

    Solid fuel engines like the kick-motor can’t be controlled because it’s impossible to stop burning the solid fuel. It’s safe to keep solid fuel for long periods in the fuel tank. In contrast, if liquid fuel is kept for a long time in the tank it could be damaged. So, usually liquid fuel is injected during the countdown.


The STSAT-2 would have rotated around the earth.
    The Naro was intended to convey the STSAT-2 but failed to reach the target orbit. Space Launch Vehicle is the rocket designed to transport things like satellites. If the Naro had accomplished its mission, the STSAT-2 would have rotated around the earth. A satellite changes its direction every moment without changing its speed. This kind of motion is called uniform circular motion. The gravity between the satellite and the earth causes the satellite move in this way.

What is the payload faring and why was there a problem?
    The payload fairing is an important part that protects the satellite from aerodynamic pressure and aerodynamic heating while passing through the atmosphere. After exiting the atmosphere, the satellite doesn’t need it anymore as the universe is almost a vacuum. So, it is better to separate it from the rocket body to gain velocity easily. 
    The first and second stage of the 140t Korea Space Launch Vehicle-1 functioned properly, but one of the two nose fairings on the rocket did not detach from the rocket on time. The added weight of the fairing that weighs 300kg, three times more than the scientific satellite, made it hard for the second stage booster to reach appropriate altitude and velocity according to the Korea Herald.
    We saw several things about the Naro. If you want to learn more about it and about aerospace science and technology, go to the Korea Aerospace Research Institute website http://www.kari.re.kr.

By Lee Shin-ae, Reporter


ⓒ 효원헤럴드(http://herald.pusan.ac.kr) 무단전재 및 재배포금지 | 저작권문의  

   * 200자까지 쓰실 수 있습니다. (현재 0 byte/최대 400byte)
   * 욕설등 인신공격성 글은 삭제 합니다. [운영원칙]
Tel 510-1937,1496 | Fax 051-581-4695 | 청소년보호책임자 서원욱
Copyright 2006 효원헤럴드. All rights reserved. mail to webmaster@herald.pusan.ac.kr
효원헤럴드을 통해 제공되는 모든 콘텐츠(기사 및 사진)는 무단 사용, 복사, 배포시 저작권법에 저해되며, 법적 제재를 받을 수 있습니다.