Terra has resumed normal operations after entering a "safe-hold" on the fourth day of the mission. Due to the unique location of the Sun during the winter solstice, which Terra uses to navigate, a computational error resulted in the "safe-hold." Terra's software will be updated to avoid future solstice-related errors.

"Overall the mission is going extremely well, with the performance of both the team and the spacecraft superb," said Kevin Grady, Terra project manager at NASA's Goddard Space Flight Center, Greenbelt, Md. "All of the activities planned to be completed by mission day 5 have now been accomplished, with the exception of the turn-on of one of the instrument outgas heaters. A number of spacecraft components have been powered-on over the past three days, and the performance of these have been excellent."

Activation of the Terra spacecraft, which was launched on Saturday, December 18th, is continuing, with the mission going extremely well. A number of spacecraft components have been powered-on over the past two days, and the performance has been nominal.

A new generation of Earth science -- one that studies the Earth's land, oceans, air, ice and life as a total global system -- began with a picture perfect launch this afternoon of the "Terra" spacecraft from Vandenberg Air Force Base, Calif. Formerly known as "EOS AM-1," the Terra spacecraft lifted off at 1:57 p.m. EST on an Atlas IIAS rocket.

With new tools and technology, scientists are getting a first look at strange features and puzzling behaviors on the frozen Antarctic continent. Icy tributaries feed giant, frozen streams that churn icebergs into the sea. Rows of long, sinuous snow dunes on the East Antarctic plateau are blown by fierce, constant winds, but appear to stay frozen in place for decades. These latest findings by Antarctic researchers were reported at the Fall American Geophysical Union meeting in San Francisco.

The images acquired by the new Landsat 7 spacecraft launched in April have exceeded scientists' expectations. With the satellite's state-of-the-art instrument and new computer ground systems, researchers have closely monitored erupting volcanoes in Hawaii, Italy and Latin America; the severe drought in the mid-Atlantic region; and the devastating floods in North Carolina. In addition to its observations of natural disasters, Landsat is offering scientists a detailed look at unique weather and cloud formation phenomena, and glacial retreats and advances.

The Clouds and the Earth's Radiant Energy System (CERES) instruments from NASA Langley Research Center, to be launched on the Terra spacecraft, will be part of an international effort to obtain a comprehensive look at the Earth system. CERES will study the Earth's radiation balance, the energy that reaches the Earth from the Sun and the energy radiated from Earth into space. "We are looking for a whole new level of accuracy in these radiation energy flows," said Langley's Bruce Wielicki, one of the lead scientists for the CERES project.

NASA will flight-test an instrument using new technologies to measure elements of Earth's atmosphere and to support space research aimed at reducing risks from severe weather. This measurement concept has been selected as the next Earth-observing mission under NASA's New Millennium Program. The mission, known as "Earth Observing 3," will test advanced technologies for measuring temperature, water vapor, wind, and chemical composition. Such sophisticated measurements have the potential for revolutionary improvements in weather observation and prediction.

The 1997-98 El Niño/La Niña had an unprecedented roller-coaster effect on the oceanic food chain across a vast swath of the Pacific, plunging chlorophyll levels to the lowest ever recorded in December 1997 and spawning the largest bloom of microscopic algae ever seen in the region the following summer. According to new results published in the Dec. 10 issue of the journal Science, El Niño also dramatically reduced the amount of carbon dioxide normally released into the atmosphere by the equatorial Pacific Ocean.

For the first time, scientists placed space-based observations of Arctic sea ice retreats into a much longer-term context and have examined the likelihood that the sea ice decreases are in part due to human-caused climate change. The team used computer climate models to examine whether the decreases observed in the ice cover of the Arctic over the past few decades are the result primarily of natural climate changes or might also be influenced by human-induced global warming, says Claire Parkinson, of NASA's Goddard Space Flight Center and a co-author of the study published in the journal Science.

A NASA Goddard Space Flight Center spacecraft has observed the lowest value of ozone ever seen in the Northern Hemisphere since spacecraft first began ozone measurements in 1978. The measurement was obtained on Nov. 30 using the Total Ozone Mapping Spectrometer (TOMS) instrument aboard NASA's Earth Probe satellite. The measurement showed 165 Dobson Units over the North Sea between Scotland and Norway. "A combination of stratospheric and tropospheric weather systems can occasionally create these extreme low ozone events," said Paul Newman of NASA Goddard. "We understand that dynamics can cause these low ozone events, but we are unsure why this event set a new record low value."