Haystack Observatory is a group of astronomical

Astronomy

Astronomy is a natural science that deals with the study of celestial objects and phenomena that originate outside the atmosphere of Earth...

 observatories

Observatory

An observatory is a location used for observing terrestrial or celestial events. Astronomy, climatology/meteorology, geology, oceanography and volcanology are examples of disciplines for which observatories have been constructed...

 owned and operated by Massachusetts Institute of Technology

Massachusetts Institute of Technology

The Massachusetts Institute of Technology is a private research university located in Cambridge, Massachusetts. MIT has five schools and one college, containing a total of 32 academic departments, with a strong emphasis on scientific and technological education and research.Founded in 1861 in...

. It is located in Westford, Massachusetts

Massachusetts

The Commonwealth of Massachusetts is a state in the New England region of the northeastern United States of America. It is bordered by Rhode Island and Connecticut to the south, New York to the west, and Vermont and New Hampshire to the north; at its east lies the Atlantic Ocean. As of the 2010...

 (USA). It is the home of the Millstone Hill Observatory

Millstone Hill Observatory

Millstone Hill Observatory is a Massachusetts Institute of Technology atmospheric sciences research centre in Westford, Massachusetts.- External links :* http://www.haystack.edu/atm/mho/index.html...

.

It has a 120 ft (37m), 171-tonne radio telescope

Radio telescope

A radio telescope is a form of directional radio antenna used in radio astronomy. The same types of antennas are also used in tracking and collecting data from satellites and space probes...

, contained within what was the largest metal-frame radome

Radome

A radome is a structural, weatherproof enclosure that protects a microwave or radar antenna. The radome is constructed of material that minimally attenuates the electromagnetic signal transmitted or received by the antenna. In other words, the radome is transparent to radar or radio waves...

. It was constructed for use in space tracking and communication in 1964. In addition, Millstone Hill is the location for two of the most well-known incoherent scatter

Incoherent scatter

Incoherent scattering is a type of scattering phenomenon in physics, which may involve various particles, such as neutrons or photons.One application is a ground-based technique for studying the Earth's ionosphere. A radar beam scattering off electrons in the ionospheric plasma creates an...

 radars in the world. These include a fully steerable 46-meter antenna, and a 67-meter fixed-zenith antenna. These radars are capable of measuring a vast array of ionospheric components, including temperature, ion concentrations, and solar wind data. Data from Millstone Hill is publicly available on the MADRIGAL database, an upper atmosphere data system managed by MIT Haystack.

Haystack Vallis

Haystack Vallis

Haystack Vallis is a valley at 4.7° N, 46.2° W on Mercury. It superficially resembles a graben but is actually a chain of overlapping secondary craters. It was named after Haystack Observatory....

 on Mercury

Mercury (planet)

Mercury is the innermost and smallest planet in the Solar System, orbiting the Sun once every 87.969 Earth days. The orbit of Mercury has the highest eccentricity of all the Solar System planets, and it has the smallest axial tilt. It completes three rotations about its axis for every two orbits...

is named after this observatory.