Later today (Nov 5 US), NEAR will take it's first snaps of Eros at a distance of approximately 4 million km (2.5 million miles). Additional pre-orbit maneuvers and tests will follow in quick succession during November and December as NEAR closes in on Eros and begins a complex orbital insertion about Eros starting December 20.

According to Scott Murchie, a member of the NEAR imaging team, "from looking at long-range spectral analysis of the properties of Eros, we expect to find a mixture of silicates and metal.

"Water in any form is extremely unlikely based both on thermodynamics and on analogy with meteorites [found on Earth] that have comparable mineralogies, he added"

NEAR was designed and built by The Johns Hopkins University Applied Physics Laboratory (APL) as the first spacecraft in NASA's Discovery program. NEAR was completed ahead of schedule and under budget for $108.4 million. In fact, APL presented a refund cheque for $3.6 million to NASA Administrator Daniel Goldin in April 1996.

Meanwhile, back in deep space NEAR's orbital insertion is expected to be completed by January 11, kicking off more than a year of intensive research via six science instruments that include;

• Multispectral Imager System
• X-ray/Gamma-Ray Spectrometer
• Near-IR Spectrograph
• Magnetometer
• Laser Rangefinder
• Radio Science

Eros was selected as the target asteroid as it is the largest near earth asteroid (NEA) that approaches Earth. It's spectral properties place it into the sub-category of S asteroids called S(IV), which is the group resembling ordinary chondrite meteorites, the most common type of fall on Earth (about 80% of the total falls).

Murchie says this makes Eros a large and interesting asteroid that is perhaps representative of the type of asteroidial source for most of the common meteorites falling on Earth.

For the commercial space industry, the NEAR mission represents a major milestone on the road to commercial exploration and development of asteroid resources.

Although the distances of NEA objects can vary from zero at the time of deep impact to over 300 million kms when on the opposite side of the sun, the fact that their orbits bring them close to earth on a regular basis makes them ideal sources of commodity resources. As the amount of energy required to reach an asteroid and leave its orbit is far less than the Moon or Mars, let alone Earth.

The NEAR spacecraft is now being operated from a control center at the Applied Physics Laboratory. The mission is managed by the Laboratory for NASA's Office of Space Science, Washington, D.C. NEAR is the 55th spacecraft built and launched by JHU/APL, which has been building spacecraft, on short schedules, under budget for more than a quarter century.

The Discovery Program marks a new, cost-conscious era in planetary exploration. NASA guidelines for Discovery missions require that the missions be completed within a 36-month development cycle and a maximum $150 million budget for spacecraft development and launch. NEAR, the first NASA planetary mission to be conducted by a non-NASA space center, was launched Feb. 17 from Cape Canaveral in Florida, after just 26 months of development. Although the mission was awarded to APL based on an estimated $112 million cost (in FY92 dollars), the actual cost turned out to be approximately $108.4 million: a $3.6 million savings for NASA.