Astronomy Picture of the Day (APOD)

[Nía]

Going for Atmospheric GOLD

In late January 2018, NASA’s Global-scale Observations of the Limb and Disk (GOLD) instrument was launched into space aboard a commercial satellite. GOLD is novel in two ways: it marks the first time that a NASA science mission is flying an instrument as a commercially hosted payload, and it is the first time scientists will monitor the daily and hourly weather of the uppermost parts of Earth’s atmosphere where it meets the edge of space.

The instrument was launched on January 25 on an Ariane 5 rocket attached to SES-14, a communication satellite. On January 28, GOLD was briefly powered on to make sure it was working, then shut back down for the transit to orbit. The satellite and instrument are now moving toward their final position in a geostationary orbit. The mission is being led by the University of Central Florida.

Space is not completely empty: It is teeming with fast-moving, charged particles and with electric and magnetic fields that guide their motion. At the boundary between Earth’s atmosphere and space, the charged particles of the ionosphere co-exist with the upper reaches of the neutral atmosphere, or thermosphere. The two commingle and influence one another constantly. This interplay is the focus of the GOLD mission.

“The upper atmosphere is far more variable than previously imagined, but we don’t understand the interactions between all the factors involved,” said Richard Eastes, mission principal investigator at the University of Colorado. “That’s where GOLD comes in: For the first time, the mission gives us the big picture of how different drivers meet and influence each other.”

Source: NASA Earth Observatory Image of the Day, 2018 March 18