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Previous space missions

Since its founding, the institute has build and launched many different types of missions on balloons, rockets, and as free-flying satellites in space. The Institute was first called the "Center for Space Research" (CSR) before it became the "MIT Kavli Institute of Astrophysics and Space Science" (MKI) as described in more detail in the History. CSR/MKI has launched ballon or rocket missions, managed complete satellites, or built instruments to be integrated into bigger spacecraft.

This picture shows a timeline of about a dozen space missions, about a dozen sounding rocket flights and a 22 ballon flights.

Space missions from 1966 to about 1980 that were run enitrely by the Center for Space Research (the predecessor of MKI today) or where hardware was built at the CSR.

After about 1980, the frequency of missions reduced, but scientists and engineers at the CSR continued to build and support instruments in larger spacecraft and observatories. Some of the more notable large missions with CSR contributions are described next.

Faraday cups on Voyager and other missions

MIT's space plasma group designed and operated "Faraday cups" on several different missions throughout the solar system. A Faraday cup measures charged particles flying through space, for example from the solar wind or from volcanos on Jupiter's moon. Faraday cup detectors were first built at MIT for the Explorer 10 mission in 1961 and are still used today, for example on Parker Solar Probe that studies the conditions very close to the Sun. From the host of missions, the Faraday cups on the Voyager 1 and 2 space craft have gone the furthest: They were originally designed for a 4 year lifetime, but e.g. the Faraday cup on Voyager 2 was launched in 1977, and switched of to conserve the remaining power of the spacecraft in 2024 at a distance of 15 billion miles to the Earth. The Voyager spacecraft are the only human-made objects to leave the solar system, and the Faraday cup was essential to measure the transition from the solar wind bubble to interstellar space.

The Plasma Science Experiment (OSE) on the voyager spacecraft consists of four Faraday cups: Three of them point in slightly different directions to measure the speed of the solar wind, and a forth one is mounted perpendicular to the others.
Credit: NASA/JPL-Caltech/MIT

Advanced Satellite for Cosmology and Astrophysics (ASCA)

The Astro-D (ASCA) satellite was a Japanese space mission with some instruments contributed by NASA. It launched in 1993 and re-entered the Earth's atmosphere in 2001 after more than eight years of successful observations. One of the main instruments was the first photon-counting X-ray CCD Camera ever flown, called Solid State Imaging Spectrometer (SIS). The SIS was developed and built at the MIT CCD Laboratory under the leadership of George Ricker  and performed over 3000 observations over the lifetime of the mission. While many different types of objects were observed, one of the strengths of photon-counting CCDs, first demonstrated by the SIS, is that for each photon, the arrival time, location, and energy is recorded, which allows the scientist analyzing the data to extract a spectrum at every location, which can reveal which elements are producing the X-ray light, and how hot they are.

Data from the SIS detector on ASCA contains so much information, that the same data needs to be displayed in different formats to see all the information; shown here is one of many ASCA observations of the supernova remnant Cas A. On the left, an image is shown. The remnant is roughly spherical and brighter on the edges where a spherical shock wave runs into the interstellar medium; it is fainter in the middle. At the same time, the data contains information about the energy of every photon. That is shown on the right in the form of a spectrum. In that spectrum, the SIS can distinguish the photons coming from different elements in the gas of the supernova remnant. The most prominent features in the spectrum are labelled with the chemical elements that emit those photons.

High Energy Transient Explorer-2 (HETE-2)

HETE-2 was the first satellite mission entirely devoted to the study of gamma-ray bursts (GRBs). The construction and testing of the spacecraft bus and the satellite control software were the responsibility of MIT. The optical camera and soft X-ray camera systems were also constructed in the CCD Laboratory. After it was launched in October 2000, the satellite and its instruments were managed from a control Center at MIT on the 4th floor of what today is called the McNair building (building 37). MIT was also responsible for the primary ground station at Kwajalein and the burst alert stations at Ascension, Gabon, Kwajalein, Kiribati, and Galapagos. The network of tracking stations allowed constant communication with the satellite so that the location of any detected GRB could be send out to other astronomers within 20 seconds of the burst detection. Over a six year mission, HETE-2 detected and provided locations for over 100 GRBs on the sky including several classes of GRBs that had not been studied or were not even known before.

The Rossi X-ray Timing Explorer (RXTE)

RXTE was named after MIT’s Bruno Rossi and was launched in 1995. It hosted several instruments of which MKI provided the All Sky Monitor (ASM) and the on-board data system. The ASM observed 80% of the sky every 90 minutes. On the one hand, this allowed RXTE to quickly detect flares or brightening of X-ray sources in the sky, on the other hand, adding data for multiple orbits together, scientists can build up a long-term record of how the brightness of an X-ray source changed over time. RXTE performed observations for over 16 years and re-entered the atmosphere on 2018. With 16 years of operations, RXTE vastly outperformed initial expectations and observed many different types of objects, in particular the hot disks around black holes and neutron stars. One especially outstanding result that CSR scientists obtained with RXTE was the observation of "frame dragging" - an effect of Einstein's theory of relativity that had been theoretically predicted about 80 years before RXTE could provide the first observational proof.

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