Artist drawing of Landsat-5 in space (Image: USGS)

The longest operating Earth-observing satellite is about to be decommissioned by the US Geological Survey.

The USGS has begun the task of lowering Landsat-5 from its operational orbit.  The first series of maneuvers in that effort is likely to take place within the next month.

Landsat-5 was the fifth of seven satellites launched as part of the Landsat program, which has been acquiring satellite imagery of Earth since 1972.

Launched from California on March 1, 1984, Landsat-5 has circled Earth more than 150,000 times.

According to the USGS, which helps manage the mission, the satellite has been an extraordinary success, providing valuable contributions to the global record of land change.

Its original mission was only supposed to last three years, but Landsat-5 continued to deliver imagery and data for more than 25 more years beyond that.

The satellite experienced a number of problems over the years, but scientists and technicians managed to bring it back from the brink of failure.

This image of the abandoned city of Pripyat, home to the Chernobyl Nuclear Power Plant was taken by Landsat-5 three days after the April 26, 1986, nuclear accident. (NASA)

However, the recent failure of one of its gyroscopes proved to be one problem too many, finally bringing Landsat-5′s decades-long mission to an end.

“This is the end of an era for a remarkable satellite, and the fact that it flew for almost three decades is a testament to the NASA engineers and the USGS team who launched it and kept it flying well beyond its expected lifetime,” said Anne Castle, Department of the Interior assistant secretary for Water and Science. “The Landsat program is the gold standard of satellite observation, providing an invaluable public record of our planet that helps us tackle critical land, water, and environmental issues.”

Over more than a quarter of a century, Landsat-5  observed and sent back Earth imagery and data  reflecting the many changes which have taken place on our planet, not only from natural hazards and a changing climate, but also due to land use practices.

It observed the eruption of Mount Saint Helens, the 1991 Kuwaiti oil fires set by a fleeing Iraqi military, the 1986 Chernobyl nuclear disaster, as well as rainforest depletion, wildfires, floods, global crop production, and the expansion and retreat of the Earth’s ice shelves.

Image taken by Landsat-5 in 1991 shows inky-black smoke pouring from burning oil wells which were set afire by defeated Iraqi military forces as they retreated from Kuwait. (NASA)

“Any major event since 1984 that left a mark on this Earth larger than a football field was likely recorded by Landsat-5, whether it was a hurricane, a tsunami, a wildfire, deforestation, or an oil spill,” said USGS Director Marcia McNutt. “We look forward to a long and productive continuation of the Landsat program, but it is unlikely there will ever be another satellite that matches the outstanding longevity of Landsat-5.”

Landsat-5 observations have helped increase our understanding and awareness of the impact humans have on the land, according to the USGS.

With Landsat-5 out of commission, a number of Earth-observing satellites put into space by other governments and private companies, continue to operate.

Landsat-7, which launched in 1999, and the upcoming  Landsat-8 (LDCM), which launches in 2013, will take up where Landsat-5 left off, continuing to keep watch over an ever-changing planet.

One of the newly identified species of slow loris, Nycticebus kayan. (Photo: Ch’ien C Lee)

An endangered lemur-like primate with two tongues and a toxic bite has more branches on its family tree than originally thought.

Writing in the American Journal of Primatology, Missouri researchers say they’ve identified three new species of the slow loris – the only venomous primate in the world – living on the Indonesian island of Borneo.

At first glance, with its big brown eyes and teddy-bear face, this nocturnal mammal appears cute and cuddly, but it’s got a lethal bite, which can cause fever, pain and swelling. For humans who suffer from allergic reactions, it can also be deadly.

Due to a benign appearance, and its uses in traditional medicine, the slow loris is a favorite of poachers throughout southeastern Asia and its surrounding islands.

The three newly identified species were originally grouped with another species. Now that the slow loris has been divided into four distinct classes, its risk of extinction is greater than previously believed. However, in the long run, it could also help efforts to protect the primate.

“Four separate species are harder to protect than one, since each species needs to maintain its population numbers and have sufficient forest habitat,” says lead author Rachel Munds from University of Missouri. “Unfortunately, in addition to habitat loss to deforestation, there is a booming black market demand for the animals. They are sold as pets, used as props for tourist photos or dismembered for use in traditional Asian medicines.”

The teeth of a juvenile slow loris are removed by an animal trafficker. (Photo: International Animal Rescue)

Munds says slow lorises are not and cannot be domesticated and that keeping them as pets is cruel. The primates are protected under the Convention on International Trade in Endangered Species.

“Zoos rarely succeed in breeding them,” says Munds. “Nearly all the primates in the pet trade are taken from the wild, breaking the bonds of the lorises’ complex and poorly understood social structures.”

Those who breed them as pets often pull out the teeth, depriving the the animal of its venomous bite. Many of these illegally captured primates die due to the foul conditions of pet markets.

“Once in the home, pet keepers don’t provide the primates with the social, nutritional and habitat requirements they need to live comfortably,” Munds says. “Pet keepers also want to play with the nocturnal animals during the day, disrupting their sleep patterns.”

The under-tongue of a slow loris sticks out beneath the primary tongue. (Photo: David Haring – Duke Lemur Center)

The Missouri researchers examined various museum specimens, photographs and actual live animals that had been lumped into the original single species. After noticing the animals had different body sizes, fur thickness, habitats and facial markings, scientists realized they’d identified four separate species of the slow loris rather than just the one.

Now instead of one animal listed as vulnerable by the International Union for the Conservation of Nature, there may be four endangered or threatened species.