Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

Coordinates and Map Projections

Coordinates and Map Projections

Coordinates and map projections are essential tools in accurately representing the Earth's surface for various applications, ranging from navigation to spatial analysis. The latitude and longitude coordinate system is a universally recognized framework for defining locations. Latitude specifies the distance of a point north or south of the equator, measured in degrees from 0° at the equator to 90° at the poles. Longitude indicates a location's position east or west of the prime meridian,...

Spherical Coordinates

Spherical Coordinates

Spherical coordinate systems are preferred over Cartesian, polar, or cylindrical coordinates for systems with spherical symmetry. For example, to describe the surface of a sphere, Cartesian coordinates require all three coordinates. On the other hand, the spherical coordinate system requires only one parameter: the sphere's radius. As a result, the complicated mathematical calculations become simple. Spherical coordinates are used in science and engineering applications like electric and...

Distance Measurements by Taping

Distance Measurements by Taping

Tapes are essential in surveying for accurate, durable, and short-distance measurements. Made from lightweight, nylon-coated steel, they offer flexibility and strength for rugged outdoor use. The nylon coating protects against rust and wear, extending the tape's life. Standard lengths, around 30 meters, are marked in meters and millimeters for precision.Surveyors select tapes based on site conditions and accuracy needs. Lightweight, nylon-coated tapes are commonly used for ease of handling and...

Detection of Black Holes

Detection of Black Holes

Although black holes were theoretically postulated in the 1920s, they remained outside the domain of observational astronomy until the 1970s.
Their closest cousins are neutron stars, which are composed almost entirely of neutrons packed against each other, making them extremely dense. A neutron star has the same mass as the Sun but its diameter is only a few kilometers. Therefore, the escape velocity from their surface is close to the speed of light.
Not until the 1960s, when the first neutron...

Schwarzschild Radius and Event Horizon

Schwarzschild Radius and Event Horizon

No object with a finite mass can travel faster than the speed of light in a vacuum. This fact has an interesting consequence in the domain of extremely high gravitational fields.
The minimum speed required to launch a projectile from the surface of an object to which it is gravitationally bound so that it eventually escapes the object’s gravitational field is called the escape velocity. The escape velocity is independent of the mass of the object. Merging the idea of escape velocity with the...

Kepler's First Law of Planetary Motion

Kepler's First Law of Planetary Motion

In the early 17th century, German astronomer and mathematician Johannes Kepler postulated three laws for the motion of planets in the solar system. He formulated his first two laws based on the observations of his forebears, Nikolaus Copernicus and Tycho Brahe.
Polish astronomer Nikolaus Copernicus put forth a theory that stated a heliocentric model for the solar system. According to this heliocentric theory, all the planets, including Earth, orbit the Sun in circular orbits.
On the other hand,...

You might also read

Related Articles

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

Sort by

Same author

West meets east: early Greek and Babylonian diagnosis.

Studies in ancient medicine·2006

Same author

Bloodletting in Babylonia.

Studies in ancient medicine·2006

Same author

Hippocrates, Galen and the Jews: renal medicine in the Talmud.

American journal of nephrology·2002

Same author

Kidney and urinary tract disease in ancient Babylonia, with translations of the cuneiform sources.

Kidney international·1995

Same author

Galaxies, human eyes, and artificial neural networks.

Science (New York, N.Y.)·1995

Same author

The hubble constant.

Science (New York, N.Y.)·1992

Search research articles

Related Experiment Video

Updated: Jul 12, 2026

Surface Mapping of Earth-like Exoplanets using Single Point Light Curves

Surface Mapping of Earth-like Exoplanets using Single Point Light Curves

Published on: May 10, 2020

Mapping the universe.

M J Geller, J P Huchra

Science (New York, N.Y.)

|November 17, 1989

Summary

Galaxy surveys reveal large cosmic structures like voids and the Great Wall. These findings challenge current cosmological models of matter distribution in the universe.

Area of Science:

Cosmology
Astrophysics
Large-scale structure formation

Background:

Galaxy distribution maps show large coherent structures in the nearby universe.
Voids and sheet-like structures are common features in these maps.

Purpose of the Study:

To analyze the characteristics of large-scale structures in the universe.
To investigate the implications of these structures for cosmological models.

Main Methods:

Analysis of galaxy distribution maps from astronomical surveys.
Measurement of the size and density of cosmic structures like voids and the Great Wall.

Main Results:

Identified voids with 20% below-average density and 5000 km/s diameter.

More Related Videos

Bringing the Visible Universe into Focus with Robo-AO

Bringing the Visible Universe into Focus with Robo-AO

Published on: February 12, 2013

Simulating Imaging of Large Scale Radio Arrays on the Lunar Surface

Simulating Imaging of Large Scale Radio Arrays on the Lunar Surface

Published on: July 30, 2020

Related Experiment Videos

Last Updated: Jul 12, 2026

Surface Mapping of Earth-like Exoplanets using Single Point Light Curves

Surface Mapping of Earth-like Exoplanets using Single Point Light Curves

Published on: May 10, 2020

Bringing the Visible Universe into Focus with Robo-AO

Bringing the Visible Universe into Focus with Robo-AO

Published on: February 12, 2013

Simulating Imaging of Large Scale Radio Arrays on the Lunar Surface

Simulating Imaging of Large Scale Radio Arrays on the Lunar Surface

Published on: July 30, 2020

Detected the 'Great Wall,' a massive sheet-like structure spanning at least 60 h⁻¹ Mpc x 170 h⁻¹ Mpc.

Observed that the extent of these structures is limited by survey size.

Conclusions:

The prevalence of large cosmic structures presents significant challenges to current theories of the universe's origin and evolution.
Further research is needed to reconcile observed structures with cosmological models.