Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Rocket Propulsion in Empty Space - I01:13

Rocket Propulsion in Empty Space - I

3.9K
The driving force for the motion of any vehicle is friction, but in the case of rocket propulsion in space, the friction force is not present. The motion of a rocket changes its velocity (and hence its momentum) by ejecting burned fuel gases, thus causing it to accelerate in the direction opposite to the velocity of the ejected fuel. In this situation, the mass and velocity of the rocket constantly change along with the total mass of ejected gases. Due to conservation of momentum, the...
3.9K
Rocket Propulsion In Empty Space - II01:12

Rocket Propulsion In Empty Space - II

3.6K
The motion of a rocket is governed by the conservation of momentum principle. A rocket's momentum changes by the same amount (with the opposite sign) as the ejected gases. As time goes by, the rocket's mass (which includes the mass of the remaining fuel) continuously decreases, and its velocity increases. Therefore, the principle of conservation of momentum is used to explain the dynamics of a rocket's motion. The ideal rocket equation gives the change in velocity that a rocket...
3.6K
Impact: Problem Solving01:26

Impact: Problem Solving

488
In an experiment conducted during a Mars mission, a rover propels a projectile with an initial velocity, and the projectile rebounds after colliding with the Martian surface. To ascertain the maximum height attained by the projectile after this collision, the known restitution coefficient and acceleration due to gravity are employed.
By designating the launch point as the origin and utilizing kinematic equations, the vertical component of the projectile's velocity at the point of impact is...
488
Rocket Propulsion in Gravitational Field - II01:03

Rocket Propulsion in Gravitational Field - II

2.9K
A rocket's velocity in the presence of a gravitational field is decreased by the amount of force exerted by Earth's gravitational field, which opposes the motion of the rocket. If we consider thrust, that is, the force exerted on a rocket by the exhaust gases, then a rocket's thrust is greater in outer space than in the atmosphere or on a launch pad. In fact, gases are easier to expel in a vacuum.
A rocket's acceleration depends on three major factors, consistent with the...
2.9K
Rocket Propulsion in Gravitational Field - I01:20

Rocket Propulsion in Gravitational Field - I

3.4K
Rockets range in size from small fireworks that ordinary people use to the enormous Saturn V that once propelled massive payloads toward the Moon. The propulsion of all rockets, jet engines, deflating balloons, and even squids and octopuses are explained by the same physical principle: Newton's third law of motion. The matter is forcefully ejected from a system, producing an equal and opposite reaction on what remains.
The motion of a rocket in space changes its velocity (and hence its...
3.4K
Torque Free Motion01:15

Torque Free Motion

897
The torque-free motion refers to the movement of a rigid body in space when no external torques are acting upon it. This type of motion can be observed in environments where there are no external forces or frictions, like in outer space. For example, a rotation of Mars in space is a torque-free motion. Mars is an axisymmetric object, meaning it has an axis of symmetry along which it rotates, designated as the z-axis. The rotating frame of reference is defined such that the center of mass of...
897

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Mortality among U.S. Industrial Radiographers Exposed to Ionizing Radiation, 1969-2019.

Radiation research·2026
Same author

Colossus: bridging the gap between big data and radiation epidemiology.

Journal of radiological protection : official journal of the Society for Radiological Protection·2025
Same author

Cancer Mortality after Protracted Low-level Radiation Exposure for Early and Contemporary Workers in Two Large Occupational Cohorts in the U.S. Million Person Study.

Radiation research·2025
Same author

Colossus: software for radiation epidemiological studies with big data.

Journal of radiological protection : official journal of the Society for Radiological Protection·2025
Same author

Approaches to harmonize mortality data sets in three diverse radiation worker cohorts.

Journal of radiological protection : official journal of the Society for Radiological Protection·2025
Same author

Distribution of plutonium and radium in the human heart.

Journal of radiological protection : official journal of the Society for Radiological Protection·2024

Related Experiment Video

Updated: Mar 7, 2026

Exploring the Effects of Spaceflight on Mouse Physiology using the Open Access NASA GeneLab Platform
11:08

Exploring the Effects of Spaceflight on Mouse Physiology using the Open Access NASA GeneLab Platform

Published on: January 13, 2019

12.9K

Space: The Final Frontier-Research Relevant to Mars.

John D Boice1

  • 1*National Council on Radiation Protection and Measurements, 7910 Woodmont Avenue, Suite 400, Bethesda, MD 20814-3095.

Health Physics
|February 25, 2017
PubMed
Summary

The Million Person Study (MPS) quantifies health risks from gradual, low-dose radiation exposure, crucial for astronaut safety and public health. This large-scale study provides vital data for radiation protection guidance.

More Related Videos

Mimicking a Space Mission to Mars Using Hindlimb Unloading and Partial Weight Bearing in Rats
05:54

Mimicking a Space Mission to Mars Using Hindlimb Unloading and Partial Weight Bearing in Rats

Published on: April 4, 2019

11.5K
Thermocapillary Convection Space Experiment on the SJ-10 Recoverable Satellite
07:00

Thermocapillary Convection Space Experiment on the SJ-10 Recoverable Satellite

Published on: March 11, 2020

7.9K

Related Experiment Videos

Last Updated: Mar 7, 2026

Exploring the Effects of Spaceflight on Mouse Physiology using the Open Access NASA GeneLab Platform
11:08

Exploring the Effects of Spaceflight on Mouse Physiology using the Open Access NASA GeneLab Platform

Published on: January 13, 2019

12.9K
Mimicking a Space Mission to Mars Using Hindlimb Unloading and Partial Weight Bearing in Rats
05:54

Mimicking a Space Mission to Mars Using Hindlimb Unloading and Partial Weight Bearing in Rats

Published on: April 4, 2019

11.5K
Thermocapillary Convection Space Experiment on the SJ-10 Recoverable Satellite
07:00

Thermocapillary Convection Space Experiment on the SJ-10 Recoverable Satellite

Published on: March 11, 2020

7.9K

Area of Science:

  • Radiation biology and epidemiology
  • Occupational health and safety
  • Space medicine

Background:

  • Knowledge gaps exist regarding health effects of chronic, low-dose radiation exposure.
  • Current understanding largely stems from acute, high-dose exposures (e.g., atomic bombings).
  • Astronauts face unique challenges with gradual, long-term radiation exposure during space missions.

Purpose of the Study:

  • To provide guidance for NASA's long-term space missions by assessing health risks from gradual radiation exposure.
  • To improve understanding of low-dose and low-dose-rate radiation effects for radiation protection.
  • To reduce uncertainty in risk estimates for astronauts, potentially allowing for extended space missions.

Main Methods:

  • The Million Person Study (MPS) involves over 985,000 individuals, including U.S. Department of Energy workers, nuclear utility workers, atomic veterans, and medical/radiological personnel.
  • Utilizes a large study size, broad dose range, and long follow-up periods to statistically quantify risks.
  • Compares NASA's individual risk-based system with terrestrial dose-limit systems.

Main Results:

  • The MPS is significantly larger than previous radiation exposure studies, offering enhanced statistical power.
  • The study aims to reduce uncertainty in risk projections, specifically the 95% confidence interval for risk-of-exposure-induced death (REID).
  • Enables detailed examination of sex-based differences in radiation response and evaluation of non-cancer outcomes.

Conclusions:

  • The MPS provides critical data for refining radiation protection strategies for astronauts, workers, and the public.
  • Reduced uncertainty in risk estimates can inform NASA's career exposure limits for astronauts.
  • Facilitates comprehensive analysis of diverse health outcomes beyond cancer, including neurological and cardiovascular effects.