International cooperation, discussion and agreements are needed to ensure safe, secure and peaceful outer space. At present, there are more than a thousand satellites that orbit the Earth by utilizing social, scientific and economic sciences whose benefits are exposed to billions of people around the world. However, in this article will provide a number of challenges that are now threatening, as one of them is the increasing density of orbital debris.
First, take a look in Sun-synchronous orbits (SSO), spacecraft faces an especially high risk. According to data from secure world foundation, SSO in this case is defined as a special orbit between 700 and 900 kilometres (km) above sea level which has a major use used by Earth observation satellites that collect valuable information.
More crowding in key orbits is also a space operations challenge. For instance, the geosynchronous Earth orbit (GEO) communications satellites, the equatorial orbit in which satellites appear almost stationary above Earth and these satellites increased orbital slot competition due to strong demand for satellite TV and global communication. This crowding has resulted in the possibility of interference with radio frequency and a decreasing margin of error to maintain separation from satellites. There are also security challenges with the increasing use of space. As more countries integrate space into their national military capabilities and rely on space-based information for national security, there is a growing potential for satellite disturbance to trigger or exacerbate tension and conflict in space or on Earth.
The example is uncontrolled re-entry of NASA’s UARS satellite on September 24, 2011 highlights an issue that has been building up for decades, the issue of debris in orbit around the Earth. In the meantime, as indicated by the site of the NASA Orbital Debris Program Office, there are approximately 500,000 pieces spreading in size between a large portion of an inch and four inches (1 to 10 cm), while the particle aggregate is less than a large portion of an inch, which is likely to exceed many millions.
One of examples on cooperation to tackle the space debris problem is come from United States. In February 2011, during Obama’s administration, space faring nations and space agencies set up an Inter-Agency Space Debris Coordination Committee (IADC), to exchange information on space debris research activities, survey progress on pleasant exercises, and identify alternatives to garbage moderation. Satellite and debris growth can be seen in the figure below,
Satellite Catalog Growth, Courtesy Joint Space Operations Center of U.S
Europe, Japan, Russia, and the United States have issued rules to alleviate the issue of debris, such as structuring satellites and shuttles so that they can circle rather than float in space. NASA is currently planning to create significant circumference along these lines. Driving space offices also set up a board to address the issue, as well as U.N. offices. The Committee on Outer Space’s Peaceful Use (COPUOS) is also investigating the issue.
Based on action of many countries regarding Space Debris problem, this can relate Debris is a Multilateral problem or can be said as threat for many countries. Thus, to prevent debris all countries especially Space Faring-Nations have to emphasizes and gain cooperation among countries (Multilateralism) in the world to keep world save from any debris threat.
Space Operations & The Space Environment
Therefore, to understand the overall problem of debris, it is essential to understand some of the characteristics of space operations of the past, present and future. Outer space operations have become an integral part of the global economy, which is used as a scientific activity, and have been enhanced by a security system in Sputnik 1 for 37 years. According to NASA data from 2004, orbital debris is closely related to certain operations, one of the threats being the presence of debris, is important because these debris pose a potential threat to future activities in the course of operation.
Talking about debris, have to take a look on the existence of spacecraft. Almost 23 nations and several international organizations (representing over 100 countries), according to the National Research Council’s Committee on Space Debris, a wide range of important missions have been supported, including communication, navigation, meteorology, geodesy and geophysics, remote sensing, research and rescue, materials and life sciences, astrophysics and national security. A wide range of launch vehicles place these spacecrafts in orbit. These launch vehicles, which can be solid or liquid, use several stages to place spacecraft in their desired orbit (some of which can orbit). There are several spacecrafts used to carry out their insertion maneuvers into orbit. In addition, most spacecraft are also assembled to have several driving capabilities to control attitudes and make orbital corrections.
Graph 2: Spacecraft population in Earth orbit, 1994. SOURCE: Prepared by Kaman Sciences based in part on U.S. Space Command Satellite Catalog.
Take data from NASA about reveals certain characteristics of the current population of the spacecraft. Most spacecraft reside in LEO, but in higher orbits there are three major concentrations. First is, spacecraft are concentrated in the GEO (performing Earth observation and communication missions) and next concentration of U.S. spacecraft in and near circular semi-synchronous orbits is in Global System of Positioning (GPS) and Russian Global Satellite Navigation.
There is also a significant spacecraft population in highly elliptical orbits of the Molniya type (In this report, the space activities of the former Soviet Union prior to 1992 will be referred to as “Soviet” and those of 1992 and later as either’ Russian’ or CIS, as appropriate.) About 1,400 to 1,500 km (partly due to a constellation of Russian spacecraft communication and debris from three Delta rocket break-ups and 900 to 1,000 km (partly due to Sun-synchronous remote sensing and navigation spacecraft and related debris) are notable peaks in LEO.
Since 1957, more than 3,600 space missions have left thousands of large and perhaps tens of millions in near-Earth space debris objects. In contrast to meteoroids that pass through and leave near-earth, artificial space debris orbits the earth and can remain in orbit for a long time. The U.S. officially listed 23,000 space objects and this according to data from Space Surveillance Network (SSN) has been around the Earth since the beginning of the space age, with almost one-third expected to remain in orbit for decades or hundreds of years. The image below shows the increasing number of space objects catalogued.
Graph 3: On-orbit cataloged population (corrected for delayed cataloging). SOURCE: Prepared by Kaman Sciences Corporation based in part on U.S. Space Command Satellite Catalog
Note that this figure only shows objects that are large enough to be tracked by ground radar repeatedly. There is no figure showing the vast majority of debris and they are too small to track. Objects that are not functional spacecraft in the Earth’s orbit are considered debris. Passive spacecraft serving as experimental laser platforms, atmospheric density measurements or calibration Space monitoring sensors are considered functional, as are spacecraft currently in reserve or standby status, which may be reactivated to continue their mission in the future. Every other type of Earth orbit object can be classified as one of four types of debris: non-functional spacecraft, rocket bodies, mission-related debris, and fragmentation debris.
Thus, to conclude this article. Space Debris is a real threat for many countries. In order to make the movement to tackle space debris, it should take openness and transparency among countries. This way in order to enhance public awareness of government activities and enable others to share the benefits of space use. For example, U.S through their Nasional Space Policy (NSP) especially during Obama administration, emphasizes all of Nations to use space especially on space operations conducted by transparency and openness in order to improve public awareness and also awareness of space debris as multilateral threat for World.