NASA Needs Strategic Plan to Manage Orbital Debris Efforts

Although NASA's meteoroid and orbital debris programs have responsibly used their resources, the agency's management structure has not kept pace with increasing hazards posed by abandoned equipment, spent rocket bodies, and other debris orbiting the Earth, says a new report by the National Research Council.

NASA should develop a formal strategic plan to better allocate resources devoted to the management of orbital debris.

In addition, removal of debris from the space environment or other actions to mitigate risks may be necessary.

The complexity and severity of the orbital debris environment combined with decreased funding and increased responsibilities have put new pressures on NASA, according to the report. Some scenarios generated by the agency's meteoroid and orbital debris models show that debris has reached a "tipping point," with enough currently in orbit to continually collide and create even more debris, raising the risk of spacecraft failures, the report notes.

In addition, collisions with debris have disabled and even destroyed satellites in the past; a recent near-miss of the International Space Station underscores the value in monitoring and tracking orbital debris as precisely as possible.

"The current space environment is growing increasingly hazardous to spacecraft and astronauts," said Donald Kessler, chair of the committee that wrote the report and retired head of NASA's Orbital Debris Program Office.

"NASA needs to determine the best path forward for tackling the multifaceted problems caused by meteoroids and orbital debris that put human and robotic space operations at risk."

The strategic plan NASA develops should provide a basis for prioritizing efforts and allocating funds to the agency's numerous meteoroid and orbital debris programs, the report says.

Currently, the programs do not have a single management and budget structure that can efficiently coordinate all of these activities. The programs are also vulnerable to changes in personnel, as nearly all of them are staffed by just one person.

The strategic plan, which should consider short- and long-term objectives, a schedule of benchmark achievements, and priorities among them, also should include potential research needs and management issues. The report lists these.

Removal of orbital debris introduces another set of complexities, the report adds, because only about 30 percent of the objects can be attributed to the United States.

"The Cold War is over, but the acute sensitivity regarding satellite technology remains," explained committee vice chair George Gleghorn, former vice president and chief engineer for the TRW Space and Technology Group.

Although NASA has identified the need for removing debris, the agency and U.S. government as a whole have not fully examined the economic, technological, political, and legal considerations, the report says.

Astronomers' puzzle: A forbidden star

An ancient star has been found lurking in the “forbidden zone” of star formation, which has astronomers puzzled as to how it could have formed.

Astronomers used instruments on ESO’s Very Large Telescope (VLT) to observe the star, which is called SDSS J102915+172927.

It has slightly less mass than our Sun, and could possibly be around 13 billion years old.

Stars are composed mainly of hydrogen and helium, with a small amount of heavier elements.

These heavier elements are referred to as “metals” by astronomers, but surprisingly this mysterious star is almost devoid of them. In fact, it has 20,000 times less metals than the Sun.

A team of European astronomers has used ESO's Very Large Telescope (VLT) to track down a star in the Milky Way that many thought was impossible.

They discovered that this star is composed almost entirely of hydrogen and helium, with only remarkably small amounts of other chemical elements in it.

This intriguing composition places it in the "forbidden zone" of a widely accepted theory of star formation, meaning that it should never have come into existence in the first place. The results will appear in the 1 September 2011 issue of the journal Nature.

A faint star in the constellation of Leo (The Lion), called SDSS J102915+172927 [1], has been found to have the lowest amount of elements heavier than helium (what astronomers call "metals") of all stars yet studied. It has a mass smaller than that of the Sun and is probably more than 13 billion years old.

"A widely accepted theory predicts that stars like this, with low mass and extremely low quantities of metals, shouldn't exist because the clouds of material from which they formed could never have condensed," said Elisabetta Caffau (Zentrum fur Astronomie der Universitat Heidelberg, Germany, and Observatoire de Paris, France), lead author of the paper.

"It was surprising to find, for the first time, a star in this 'forbidden zone', and it means we may have to revisit some of the star formation models."

The team analyzed the properties of the star using the X-shooter and UVES instruments on the VLT.

This allowed them to measure how abundant the various chemical elements were in the star. They found that the proportion of metals in SDSS J102915+172927 is more than 20,000 times smaller than that of the Sun.

"The star is faint, and so metal-poor that we could only detect the signature of one element heavier than helium - calcium - in our first observations," said Piercarlo Bonifacio (Observatoire de Paris, France), who supervised the project.

"We had to ask for additional telescope time from ESO's Director General to study the star's light in even more detail, and with a long exposure time, to try to find other metals."

Cosmologists believe that the lightest chemical elements - hydrogen and helium - were created shortly after the Big Bang, together with some lithium, while almost all other elements were formed later in stars.

Supernova explosions spread the stellar material into the interstellar medium, making it richer in metals. New stars form from this enriched medium so they have higher amounts of metals in their composition than the older stars. Therefore, the proportion of metals in a star tells us how old it is.

"The star we have studied is extremely metal-poor, meaning it is very primitive. It could be one of the oldest stars ever found," adds Lorenzo Monaco (ESO, Chile), also involved in the study.

HiRISE | Sulphates in Ius Chasma

HiRISE | Sulphates in Ius Chasma

HiRISE | Digital Terrain Map: Fresh Impact Crater

Fresh Impact Crater

HiRISE | DTM: Fresh Impact Crater

HiRise Digital Terrain Map

HiRise: The Gemstone Floor of Noctis Labyrinthus

HiRise: The Gemstone Floor of Noctis Labyrinthus

HiRISE | Proposed MSR Landing Site in Jezero Crater

Proposed MSR Landing Site in Jezero Crater

HiRISE | Proposed MSR Landing Site in Jezero Crater (ESP_023102_1985)

Protecting the Croatia Limestone Cave System and it's unique animal life

Species of animals, millions of years old, could be wiped out by pollution and development in Croatia according to a new breed of cave biologists.

Jana Bedek and her team of bio-speleologists have recently discovered that the underground networks of the Balkans, especially Croatia, have the richest cave fauna in the world.

"We are now in the place with the best range of cave animals in the world," she says.

"The other countries have their own rich fauna in rainforests, marine ecosystems etc, but here in this area we have cave fauna. Really important at world level."

But on a political and economic level, Croatia is emerging from decades of communism, and the devastating Balkan war, with a desire to develop.