Year of the lunar microsatellite project

The lunar microsatellite project is one year old, so it's time to tell how we are doing and to report on the work done. Immediately I admit: we do not fit into the schedule, but a lot has already been done: we have prepared a technical task, decided on the derivation scheme and orbit, conducted three iterations of the layout of the satellite platform, but first things first.

October 1, 2015 on the crowdfunding platform "Bumstarter" started raising funds for the Project of the lunar microsatellite . The purpose of the collection: the search for funds for the preparation of an advance project of a small spacecraft capable of reaching a low circumlunar orbit for high-resolution photography of the Apollo and Lunokhod landing sites. The fundraising was completed on November 5, twice exceeding the planned amount: 1.75 million rubles, instead of the requested 800 thousand rubles.


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It is impossible to build even a near-earth satellite with this money, this collection formed the basis of the first stage of the development of the spacecraft - the Description of the project. In the space industry, the description of the proposed and proposed development of a spacecraft is called “avanproekt”. It is to them that we are now busy. The preliminary design contains the results of preliminary calculations of the orbital characteristics, capabilities of the propulsion system and on-board radio complex, the design and optical capabilities of the camera, the properties of the orientation system, the power supply system and other service subsystems of the device, which will allow to accomplish the tasks.

In the future, new stages will be required, each times more complicated than the previous one: preliminary design, preparation of design documentation, preparation of an engineering layout, elaboration of work algorithms, writing software ... And many, many more, without which launching such a rather complex interplanetary spacecraft is impossible.



The initiative group of engineers with experience in the rocket and space industry or in related industries took up the realization of this goal. During the fundraising, the team included several other specialists. Several scientists have expressed their interest in the project, as having scientific perspectives in the study of the moon. Dozens of space enthusiasts from around the world responded to the project.

But expressing support or even participating in the discussion is one thing, and devoting time to development, and spending at least a few hours a week, on calculations, drawing up tables, charts, preparing a description is another. The money collected at Bumstarter has been set aside for some components and a professional examination of the project. Therefore, all the work that has already been done and is still required to prepare the project is carried out free of charge, on volunteer grounds. And such work in any chart has a lot of competitors, and only a real enthusiast is able to lead it. Often, life circumstances are stronger than any enthusiasm, for the first year of work, someone from the project participants has a new promising job that distracts almost all the time; someone already flew a ready-made spacecraft, and now all the time is busy working with it; someone had a son ... All this, of course, positive changes in life, which should only be happy, but each of them delays the implementation of our project and postpones the future start, which we hope for.

There were also inevitable difficulties of psychological compatibility of the project participants. So, it was necessary to refuse the help of radio engineering, which took upon itself the obligations of preparing the onboard radio complex. Despite the fairly high professionalism, he could not find a common language with the rest of the team. After his departure, work on the radio channel had to start from scratch. Now we are communicating with the SAIT company from Zelenograd, which is ready to take on the development of an onboard radio complex for the lunar microsatellite. For them, this is no longer a hobby, but work that we will have to pay for, or offer some other mutually beneficial terms of cooperation, but their high professionalism and experience are worth it.

Now more about what has been done. Now we have an advance project of about 70% readiness.

Finish Terms of Reference for the project .
Now you can see what we have to prepare in the near future. I hope it will turn out to finish the work before the New Year.

We chose two possible spacecraft launching schemes for which two layouts are being worked out. The first inference scheme is a launch launch into a geostationary orbit. This is the orbit of meteorological and telecommunication satellites at an altitude of about 36 thousand km in the plane of the Earth's equator. For example, the Electro-L2 satellite is working there.



About a dozen and a half of commercial launches into the geostationary orbit are carried out from Baikonur, Kourou, Canaveral. This year, Veichang was added. The derivation of a couple or more satellites has already been worked out by several space agencies and companies, although the price for each launched device can reach tens of millions of dollars. We do not have so much and are not expected, so we can only hope for a fair launch within the framework of any partnership programs or state support.

The second version of the launch is a launch to a lunar transition orbit. In fact, they were let in the direction of the Moon, and then cope as you know. Such a launch is possible only on a rocket, which leads something to the moon. Our satellite could take a place on the upper stage separately from the main payload. Moon launches are much rarer geostationary. If you consider the plans of different countries, then the lunar rockets will be about a dozen over the next ten years. The closest is the launch of the NASA SLS rocket in 2018, where in addition to the Orion ship, about a dozen US student and private Kubtsat flights will fly. Three or four Roskosmos start-ups are expected, at least one in India, several in China, there are projects in South Korea and Japan. It is assumed a pair of launches devices for the contest Google Lunar XPRIZE. In general, a small satellite has some chance to get up to launch before the moon, so this possibility is also included in the development.

Two withdrawal schemes require a significantly different fuel reserve. To resolve this issue, several options were considered: the development of a separate upper stage, the creation of two types of spacecraft, but this is unacceptable due to the limited budget and human resources. The compromise option became such: a single satellite platform and a propulsion system, differing only in the volume of fuel tanks. Such an arrangement is unnecessarily cumbersome for the “easy” option, but this is a price to pay for versatility.

Information about this arrangement was published in May 2016 . The device flying from a geostationary orbit, turned out weighing 160 kg. This is one and a half times more than what is called a microsatellite, but the Tsiolkovsky formula does not look at the terminology.

After the inclusion of the “SAIT” team, we have to revise the layout downwards. Their onboard radio complex turns out to be lighter than what we considered at the beginning, it consumes less energy, it heats less, which means we can reduce the area of ​​solar batteries, radiators, and facilitate the orientation system. Work in this direction is still underway, which is some justification that the preliminary project is not yet ready. It is unlikely that it will be possible to alleviate the migration option below 100 kg, but a significant weight loss is expected.

The design of the propulsion system has not yet been determined. We only know that the propulsion system will be a two-component UDMH / AT. This is a toxic fuel, and we do not have a permit to work with it, but we do not plan to do this either. There are enterprises in the country with both tolerance and experience in the development of such motor systems. For example, on the site of the FSUE “NIIMash” plant in Nizhnyaya Salda there was a system very similar to what we need - the propulsion system of the Phobos-Grunt return module - however, it is twice as powerful and heavier.



The working orbit is assumed to be near-circular, with an inclination of 84-85 degrees, i.e. close to polar. This means that we can only shoot the poles at an angle of up to 15.5 degrees, which is not very convenient for subsequent work with images, but acceptable. A polar orbit would be more convenient, but the chosen inclination allows one to maintain a higher level of stability, avoiding the significant influence of the moon masks. More precisely, they will, but will mutually compensate for the influence of each other. This will allow to stay in the selected orbit for a long time, without spending a lot of fuel on the correction.



The average height of the orbit is assumed to be 50 km. This is about the same as the American LRO, but at the expense of a more powerful telescope, the resolution of the images should be higher. In addition, the actual height of the satellite will constantly vary within certain limits, sometimes reaching 20-25 km. We are working to ensure that in such periods we are at the goals we need. Plus, one of the variants of the optical scheme provides for work in the blue-green part of the spectrum. This allows you to significantly raise the resolution (about 17%) without increasing the telescope dimensions at the cost of some reduction in sensitivity: a shorter wavelength moves the diffraction limit, and allows you to see smaller details on the surface with the same diameter of the telescope (of course, the optical quality of the telescope is diffractive). limited).



Since May, the telescope has remained unchanged - the prepared variants meet the requirements; you only need to select one of the options by the time the satellite’s final appearance is formed.

The calculations show the possibility of obtaining a resolution of 25 cm on the surface from a 100 km orbit (and significantly higher from lower orbits), which is twice as good as the average LRO quality. Although in the mode of maximum reduction LRO reached a resolution of 30-35 cm.



Our orbit will also allow for the reduction, which will make it possible to improve the quality of the image, and to distinguish details up to 10 centimeters or less on the surface. That is, with the optimal development of the program, it will be possible to see individual tracks, and smaller contrasting objects.

Distribution of rewards to sponsors of the project on Boomstarter continues. I held personal meetings with some of the sponsors during my lecture tours around the country, but most of the awards have not yet been sent, and this also takes time. Before the New Year also try to send most of the icons and books.