Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
1 The principle of the solar telescope The Italian Claudio Maccone has already planned a telescope which is based on the Sun as a gravitational lens (Figure 1: FOCAL). The present essay contains the principle of a solar telescope (SOLIS) which is geocentric and focusable. The SOLIS solar telescope consists of a terrestrial microwave transceiver with a preparatory-processing computer subsystem, the aerials of the microwave transceiver on the South and North Pole, a microwave transceiver on a satellite revolving synchronously with the Earth, a relay subsystem on the orbiting satellites and the Sun as a gravitational lens (Figures 2 and 3). Relay subsystem (ring-aerial) on satellites Let us set up relays as satellites revolving on the same orbit and equidistant from each other in a plane which is perpendicular to the Sun-Earth axis (Figure 3). The minimal radius of the relays’ common orbit is rmin=R(d-1)/d, where R is the radius of the Sun, d=KF1 minimum 550 AU. In the case of R=696000 km and d=550 AU, rmin=694735 km. The radius of the relays’ common orbit is „r” and rmin<r<R. It must be studied in details and distincly what value the ’r’ common orbit radius should take within this interval and what size a relay should be physically. The relays are not connected with each other, so every relay is a satellite. Every relay rotates around its own axis, which is perpendicular to its orbital plane, and the time of rotation is equal to the time of orbiting around the Earth, so they can form an integral ring-aerial. There can be another solution with several relays on a semicircularshaped satellite. The more relays the system consists of, the more effective it is, so the number of the relays has to be increased to the upper limit of the possibilities. The relay subsystem can easily be repaired. If, for example, a meteor „knocks out” a relay, the system can still work with the rest n-1 relays and the lost relay is relatively easy to replace. As the satellites in a certain relay subsystem hold their orbital plane, two objects can be observed during a calendar year. If the objects are situated behind each other on the optical axis, we can observe two or more of them. We have to choose the orbital plane of the relay subsystem, that the telescope could watch as many objects as possible in the two points of time of the year. Objects in other directions can be observed with the relay subsystem which faces there. In order to avoid collisions a minimal difference must be left in the orbital radiuses of the different relay subsystems. We can expose with every relay subsystem twice a calendar year. Relay subsystem on a single ring in the Sun-Earth librational point The relays can be installed on a connected chain-ring which can practically be situated in L1 librational point, perpendicular to the eclipse so that the ring could always face the Sun and B satellite,namely, its rotation axis must coincide with the Sun-Earth axis. The disadvantage of this solution is that, for example, a meteor-shower can do a lot of harm in this hard ring-aerial and this damage is more difficult to repair than it is if we have stand-alone satellites. On the other hand, the great advantage of a hard ring-aerial in the L1 librational point is that this system can be operated continually, not only twice a year, because the ringaerial heads for the Sun at every moment of time. In the simplest version of the system the relays of the ring-aerial can be replaced with rotatable planes which can reflect microwave rays. The operation of the solar telescope During transmission the aerial on the currant terrestrial pole transmits the microwave signal to B satellite revolving synchronously with the Earth,which forwards it to all the relays of the ring-aerial simultaneously (Figure 2). The „s” rays go along the generating lines of a cone’s surface (envelope) between the B transceiver and Ai relays. The relays of the ring- 2 aerial transmit the signal in the direction of the Sun’s edge. The b rays go along the generating lines of a truncated cone’s, the b’ rays go along those of a cylinder’s surface and the a’ rays go along those of a cone’s surface. In the upper position of the nodding relay-aerial the rays are transmitted a bit farther from the edge of the Sun and they are made parallel with the optical axis by the solar lens (Figure 2: p-s-b-b’ ray-courses). In the lower position of the nodding relay-aerial the rays are transmitted to the edge of the Sun and they are focused on F 1 point by the solar lens (Figure 2: p-s-a-a’ ray-courses). (As the relay orbits around the Earth, there is a different solar edge-point opposite the relay at every moment of time.) The Sun focuses the rays coming from the ring-aerial, so it magnifies the signal significantly. The gain is great, the intensity of the signal increases remarkably because of the focusing. If we operate the aerials of the relays between their two extreme positions (we „open them out”) continuously and simultaneously, the F focal point will cover the focal line from F1 to the infinite distant point, so we can focus on an optional target (farther than F1). As the Earth orbits around the Sun, the focal line will scan the ecliptic plane during a year. The exceptions are the inner points of the circle with KF1 radius, however, there is nothing to observe here, because the nearest star is 4 ligh-years from the Sun. The SOLIS-system can be used as a transmitter and a receiver alike. While receiving, it focuses the rays starting from F point on B point (Figure 2: a’-a-s-p or b’-b-s-p ray courses, etc.). In the case of the satellite-version, the aerials of the relay subsystem have to be able to nod between the upper and lower positions on both side of the orbital plane, because they have to nod in the opposite direction in half a year. Figure 1: Maccone’s FOCAL telescope K: Rn : KF1: F1: t: a-a’: F: p: the centre of the Sun the radius of the Sun minimum 550 AU the nearest focal point of the solar lens the optical axis rays arriving at the Sun’s edge, photosphere in parallel with the optical axis, focused on F1 by the solar lens the current focus with the microwave transceiver as an artificial satellit revolving around the Sun at an orbit with KF radius the F satellite’s orbit around the Sun 3 Figure 2: the SOLIS solar telescope T: K: R: B: the centre of the Earth the centre of the Sun the radius of the Sun the microwave transceiver (satellite around the Sun) revolving synchronously with the Earth É: the current terrestrial pole (North or South) with the aerial of the terrestrial microwave transceiver on it. The northern aerial works in summer, the southern one in winter. The changing of the aerials is at the vernal and autumnal equinox. A: the ring-aerial (relay subsystem) Ai: an element of the A relay subsystem (i=1,2,…n) a-a’: the rays grazing the edge of the Sun, which are focused on F1 by the solar lens. b-b’: the rays passing a bit farther from the edge of the Sun, which are made parallel with the optical axis by the solar lens. F1: the nearest focus of the solar lens (KF1 minimum 550 AU) F: the current focus F1-F…:the focal line p: microwave rays between the current pole of the Earth and the B microwave transceiver s: microwave rays between the B transceiver and the relay aerials 4 Figure 3: the ring-aerial (relay subsystem) a/ from the direction which is perpendicular to its orbital plane b/ from the direction of its orbital plane with the B satellite T: the centre of the Earth A: the orbit of the ring-aerial (relay-subsystem) Ai: an element of the A ring-aerial, i.e. a „nodding” relay aerial Fi: the rotation axis of the Ai nodding relay aerial Af: the „upper” position of the Ai rodding relay aerial Aa: the „lower” position of the Ai nodding relay aerial s: microwave rays between the B microwave transceiver and the relay aerials 5 Figure 4: The FOCAL system and the SOLIS system As the Earth orbits around the Sun, the focal line scans the ecliptic plane during a year.When the focal line approaches an object we want to observe and we know its distance, we focus the system on the object by the turning of the relay aerials. If we do not know the distance of the object, we have to search for it in the whole angle-domain (between the „upper”and „lower” positions). The relay subsystem can be set up with fixed aerials instead of the nodding ones. In this case , the fixed aerials are practical to direct on p-s-b-b’ ray courses (Figure 2). The SOLIS-system can be operated in the visible light domain if we use plane-mirrors instead of the microwave relays and a light-source or a photon-detector instead of the microwave transciever. 18th January, 2003 Bölcsföldi József physicist Gábor Dénes College Hungary Claudio Maccone: Almár Iván: THE SUN AS A GRAVITATIONAL LENS: PROPOSED SPACE MISSIONS (IPI Press, Colorado Springs, Colorado, 1999) A SETI SZÉPSÉGE. Kutatás Földön kívüli civilizációk után. (Vince Kiadó, 1999)