Theory:

Meanings of difficult words from the lesson "An Indian-American woman in space - Kalpana Chawla":
 
No.WordMeaning
1
PrologueA special section that introduces the lesson.           
2
SummariseTo explain any lengthy topic in a few short lines.
3
InboundTo travel towards a target.
4
On-boardTo be inside any vehicle that travels.
5
VictimAny person who has been harmed or killed.
6
Graduating
To successfully complete a specific course of study and earn a certificate in the process.
7
UndergoTo go through anything for a long duration.
8
LiberalTo keep an open mind to agree to different ideas.
9
BachelorAny person who has completed his or her bachelor's degree.
10
DoctorateThe highest awarded degree to any student pursuing a subject, also called a Ph.D.
11
HistoricAn event so great it would be recorded in World History books.
12
NaturalisationTo gain citizenship in a foreign country by marriage. 
13
HarshA condition where survival is hard.
14
ImmersedTo be completely absorbed in.
15
PerishedTo die a horrible death.
16
AstrophysicsA branch of astronomy that deals with the physical conditions of stars and planets.
17
AdvanceTo move forward.
18
UnparalleledSomeone or something that has no equal.
19
CountlessIn great, uncountable numbers.
20
AspirantsAny person who aims to achieve something great.
21
Flight InstructorAny person with enough experience to teach others to fly airplanes.
22
SpecialisationThe act of gaining in-depth knowledge through years of study in a subject.
23
CrewA group of people who work together to operate big vehicles like ships and shuttles.
24
Lift-offTo launch into space using a rocket or space shuttle.
25
DisasterA sudden accident that causes great loss of life.
26
JournalistAny person whose profession is related to announcing news to the public.
27
InspirationAny person who gives hope for future generations to achieve something great.
28
ExperimentationThe art of performing experiments for the advancement of Science.
29
VisionTo look into the future in a logical manner.
30
Launch padThe place from which rockets are launched into space.
31
AstronautA person trained to survive in outer space.
32
InstructorA person who is trained to teach others in a subject of study.
33
PursueThe act of following a subject for study.
34
Space ShuttleA vehicle of transport used to go to outer space.
35
SurviveThe ability to escape disaster.
36
JourneyAn act of travelling from one place to another.