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NASA Imager for Magnetopause-to-Aurora Global Exploration (IMAGE)

In late 2005, NASA lost one of its satellites called Imager for Magnetopause-to-Aurora Global Exploration (IMAGE).

IMAGE was launched from Vandenberg AFB on March 25, 2000; its mission was to observe the Earth’s magnetosphere, and how it is affected by solar wind. See Figure 1.

Figure 1

Magnetic fields, known as the magnetosphere, surround Earth. Shown here is an artist's conception of the constant stream of particles flowing by from the solar wind. The solar wind speed variations buffet the Earth's magnetic field and produce storms in the Earth's magnetosphere. (Image courtesy of NASA)

Magnetic fields, known as the magnetosphere, surround Earth. Shown here is an artist’s conception of the constant stream of particles flowing by from the solar wind. The solar wind speed variations buffet the Earth's magnetic field and produce storms in the Earth's magnetosphere. (Image courtesy of NASA)

The solar wind emanates from the Sun in all directions at speeds of about 400 km/s (about 1 million miles per hour). The source of the solar wind is the Sun's hot corona. The temperature of the corona is so high that the Sun's gravity cannot hold on to it. We do understand why this happens; however, we do not understand the details about how and where the coronal gases are accelerated to these high velocities. See Figure 2

Figure 2

IMAGE and the Solar Wind (Image courtesy of NASA)

IMAGE and the Solar Wind (Image courtesy of NASA)

IMAGE utilizes neutral atom, ultraviolet, and radio imaging techniques to study the Solar Wind. A suite of three neutral atom imagers (NAI) provided energy- and composition-resolved images at energies from 10 eV to 200 keV with a time resolution of 300 seconds. Two ultraviolet imagers, covering wavelength ranges from 120-180 nm and provide coverage in the Far UltraViolet (FUV) and 30.4 nm Extreme UltraViolet (EUV). The radio plasma imager (RPI) is a low-power RADAR which operates in the radio frequency bands that contain the plasma resonance frequencies characteristic of the Earth's magnetosphere (3 kHz to 3 MHz).

Recently, an amateur astronomer, Scott Tilley in Roberts Creek, British Columbia, amazingly found NASA’s IMAGE spacecraft more than 12 years after it went dark.

Figure 3

The IMAGE spacecraft at NASA being constructed and tested prior to year 2000 launch (Image courtesy of NASA)

The IMAGE spacecraft at NASA being constructed and tested prior to year 2000 launch (Image courtesy of NASA)

As of Thursday, February 1, 2018 the first data files, indicating the state of the spacecraft, have been successfully decoded. NASA’s IMAGE team found that the spacecraft’s battery is fully charged at 100%, and its temperature is in line with those in 2005 when it was lost.

Engineers at The Johns Hopkins University Applied Physics Lab (APL) continue to capture IMAGE data. The spacecraft has two sets of redundant hardware: Primary side A and backup side B. Scientists have determined that they are now running again on Side A of the Power Distribution Unit (PDU) – a surprise since it had been thought that the side A was dead after a presumed power failure on Thanksgiving Day in 2004 when it switched to its backup Side B hardware.

The ultimate cause of the current reboot is still not known, but NASA findings suggest that a reboot in some form has in fact, occurred.

The data indicate an overall healthy spacecraft. The next steps for the IMAGE team are to see if they can do more than just listen to the spacecraft, and talk back to it. NASA team efforts are still underway. More on this effort coming soon on Planet Analog regarding the IMAGE on board imagers like the Radio Plasma Imager (RPI), the Medium Energy Neutral Atom (MENA) imager, and the Low Energy Neutral Atom (LENA)

Also see

How NASA helps Earth in natural disasters

NASA TDRS-M communications satellite

2 comments on “NASA Imager for Magnetopause-to-Aurora Global Exploration (IMAGE)

  1. D Feucht
    February 17, 2018

    Steve,

    Interesting report. We usually think of space as a hostile vacuum but it is even harsher – filled with plasma.

    The IMAGE data could be useful in designing satellites because their surfaces are impacted by plasma. In low-earth orbit (LEO), the plasma density is relatively high but at low energy, so the best protection from charge buildup on  satellite surfaces is to insulate them. At low energy, the voltage difference between isolated panels is low – a few volts.

    However at GEO, the situation is different; plasma is low-density but high energy, and for high-altitude protection, conductive coatings are put on the outer panels to short them and prevent a charge build-up, which could otherwise result in over 1000 V differences and arcing.

    We live in an electrical solar system!

  2. Steve Taranovich
    February 18, 2018

    Thanks Dennis, for adding this important information which rounds out the plasma story

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