Manfred Memorial Moon Mission (4M) was the first private lunar probe to successfully fly by the Moon. It was led by LuxSpace, a child company of German OHB System, and named in honor of OHB Systems founder, Manfred Fuchs, who died in 2014. It was launched with the Chinese Chang'e 5-T1 test spacecraft on 23 October 2014. The lunar flyby took place on 28 October 2014, after which the spacecraft entered elliptical Earth orbit and continued transmission until 11 November 2014, exceeding its designed lifetime by four times. The spacecraft, along with the rocket stage to which it was attached, likely made impact with the surface of the Moon after its orbit decayed, on 4 March 2022. This made Luxembourg the eighth country to reach the surface of the Moon.

Spacecraft

The briefcase-sized probe, with a mass of 14 kg was built by the Luxemburg company LuxSpace. Its primary power source consisted of 28 non-rechargeable Saft LSH20 HTS lithium cells, which provided 4.5 W power for the payload electronics. It was permanently attached to the

Long March 3C The Long March 3C (), also known as the Changzheng 3C, CZ-3C and LM-3C, is a Chinese orbital launch vehicle. It is launched from Launch Complex 2 and 3 at the Xichang Satellite Launch Center (XSLC). A three-stage rocket with two strapon liquid ...

/G2 upper stage through the mission, and its design was adapted to function near the electromagnetic interference from the rocket's 1 kW

S band The S band is a designation by the Institute of Electrical and Electronics Engineers (IEEE) for a part of the microwave band of the electromagnetic spectrum covering frequencies from 2 to 4 gigahertz (GHz). Thus it crosses the conventiona ...

transmitter. The secondary power source included 4 Saft MPS

lithium-ion batteries A lithium-ion or Li-ion battery is a type of rechargeable battery that uses the reversible intercalation of Li+ ions into electronically conducting solids to store energy. Li-ion batteries are characterized by higher specific energy, energy ...

recharged by a 2x8 grid of

solar panels A solar panel is a device that converts sunlight into electricity by using photovoltaic (PV) cells. PV cells are made of materials that produce excited electrons when exposed to light. These electrons flow through a circuit and produce direct ...

, to recharge its batteries. Unlike the primary power source, however, it was dependent on the spacecraft

attitude Attitude or Attitude may refer to: Philosophy and psychology * Attitude (psychology), a disposition or state of mind ** Attitude change * Propositional attitude, a mental state held towards a proposition Science and technology * Orientation ...

(orientation) and rotation rate, determining the availability of sunlight to recharge the batteries. The onboard computer was an FM430.

Payload

;

Amateur radio Amateur radio, also known as ham radio, is the use of the radio frequency radio spectrum, spectrum for purposes of non-commercial exchange of messages, wireless experimentation, self-training, private recreation, radiosport, contesting, and emer ...

The radio payload consisted of a quarter-wave

monopole antenna A monopole antenna is a class of radio antenna consisting of a straight rod-shaped conductor, often mounted perpendicularly over some type of conductive surface, called a ground plane. The current from the transmitter is applied, or for rece ...

supported by an I/Q modulator, and an

RF power amplifier A radio-frequency power amplifier (RF power amplifier) is a type of electronic amplifier that converts a low-power radio-frequency (RF) signal into a higher-power signal. Typically, RF power amplifiers are used in the final stage of a radio tra ...

providing 1.5 W power. The probe's antenna transmitted up to 2,500, 13-character digital messages at 145.980 MHz using digital mode JT65B, with additional tone transmissions. LuxSpace created a contest with prizes for

amateur radio operator An amateur radio operator is someone who uses equipment at an amateur radio station to engage in two-way personal communications with other amateur operators on radio frequencies assigned to the amateur radio service. Amateur radio operators ...

s to receive these transmissions and send results back to the company. The radio was activated 77.8 minutes after the launch, and the first radio signal was received in

Brazil Brazil, officially the Federative Republic of Brazil, is the largest country in South America. It is the world's List of countries and dependencies by area, fifth-largest country by area and the List of countries and dependencies by population ...

at 19:18 UTC. The team expected 10 participants to join the contest, but more than 60 people took part. Scoring was based on the number of messages received. ;Dosimeter The 4M probe featured a small

dosimeter A radiation dosimeter is a device that measures the equivalent dose, dose uptake of external ionizing radiation. It is worn by the person being monitored when used as a personal dosimeter, and is a record of the radiation dose received. Modern el ...

that measured

ionizing radiation Ionizing (ionising) radiation, including Radioactive decay, nuclear radiation, consists of subatomic particles or electromagnetic waves that have enough energy per individual photon or particle to ionization, ionize atoms or molecules by detaching ...

in space. The instrument was provided by the Spanish company iC-Málaga. The instrument measured the total ionizing dose every 5 minutes, and it showed a significant increase in radiation doses while crossing

Van Allen radiation belt The Van Allen radiation belt is a zone of energetic charged particles, most of which originate from the solar wind, that are captured by and held around a planet by that planet's magnetosphere. Earth has two such belts, and sometimes others ma ...

s. 215 hours into the mission, the radiation sensor stopped working for unknown reasons.

Mission

The probe was permanently attached to the third stage of

/G2 on 23 October 2014 at 18:00 UTC along with Chang'e 5-T1, making its closest flyby a day after Chang'e 5-T1. The lunar flyby took place during the night of 28 October 2014. After that, the probe entered a highly elliptical

geocentric orbit A geocentric orbit, Earth-centered orbit, or Earth orbit involves any object orbiting Earth, such as the Moon or artificial satellites. In 1997, NASA estimated there were approximately 2,465 artificial satellite payloads orbiting Earth and 6,21 ...

with a period of 14 days and it remains in space. The last transmission from the spacecraft was received on 11 November 2014, 01:35 UTC. It is expected that the booster, along with 4M, should have impacted the Moon on March 4, 2022, near the Hertzsprung crater. A campaign to reacquire radio contact with the probe, knowing it could theoretically be reactivated depending on the orientation of the solar panels, was performed both by radioastronomers and amateurs, but without success.

Honorifics

The 4M probe was the first private lunar probe to successfully perform a lunar flyby. A similar flyby on 13 May 1998 by the PAS-22 satellite, at the time called HGS-1, a

geostationary A geostationary orbit, also referred to as a geosynchronous equatorial orbit''Geostationary orbit'' and ''Geosynchronous (equatorial) orbit'' are used somewhat interchangeably in sources. (GEO), is a circular geosynchronous orbit in altitud ...

communications satellite A communications satellite is an artificial satellite that relays and amplifies radio telecommunication signals via a Transponder (satellite communications), transponder; it creates a communication channel between a source transmitter and a Rad ...

made a lunar flyby in a recovery attempt after a partially failed launch that left it on an unusable highly elliptical orbit. Using

gravity assist A gravity assist, gravity assist maneuver, swing-by, or generally a gravitational slingshot in orbital mechanics, is a type of spaceflight flyby (spaceflight), flyby which makes use of the relative movement (e.g. orbit around the Sun) and gra ...

manoeuvres, the satellite was successfully recovered on 17 June. Unlike the 4M mission, the HGS-1 was not designed as a lunar mission, and made a flyby only in a recovery attempt, however according to Hughes Global Services, the satellite operator at the time, it claimed the title of the first commercial mission to the Moon. The first commercial payload to the surface of the Moon was by Celestis,About the Luna 01 Flight.
Celestis. Accessed 14 July 2018. that paid for commercial transportation of a human remains memorial on board the ''

Lunar Prospector ''Lunar Prospector'' was a spacecraft that orbited the Moon for 19 months in 1998-99. From a low polar orbit, it mapped surface composition including lunar hydrogen deposits, measured magnetic and gravity fields, and studied lunar outgassing e ...

'', which impacted the Moon's surface on 31 July 1999.

References

External links