Astrometric and photometric observations of comet 29P/Schwassmann-Wachmann 1 ​at the Sanglokh international astronomical observatory

Abstract

Although the comet has a short period of revolution it is regarded to be an object of the Centaurs group. Comet was exhibited a new activity this period which we used for analysis of its features. The coordinates of comet were determined and the orbit was calculated, the apparent and absolute magnitudes in BVRI bands were determined, as well the comet color indices and the estimation of nucleus diameter were obtained. From investigations of morphological features we identified two dust structures in the coma.

Initial Costate Approximation for Rapid Orbit Raising with Very Low Propulsive Acceleration

“…Finally, the value of R t ≃ 1 in all the transfers analyzed indicates that the expression of the flight time given by Equation ( 29) is well suited to rapidly calculate the minimum transfer time without solving (numerically) the optimization problem, especially for low propulsive acceleration magnitude. The proposed method is now used to rapidly solve the TPBVP associated with the (heliocentric) minimum-time transfer towards comet 29P/Schwassmann-Wachmann 1 [24][25][26][27]. The latter was very recently considered by the author [28] as a potential target for a solarsail-based (rendezvous) interplanetary mission.…”

Solar Sail Transfer Trajectory Design for Comet 29P/Schwassmann–Wachmann 1 Rendezvous

“…Comet SW1, which was discovered on 15 November 1927 by German astronomers Arnold Schwassmann and Arno Wachmann, currently covers a nearly circular orbit between Jupiter and Saturn with a small inclination to the Ecliptic [4], as sketched in Figure 1. This periodic and active comet, whose orbital period is roughly 15 years, is an interesting and still unexplored small body that has been regarded as an object of the Centaurs group [5][6][7], that is, a celestial body originating from the Kuiper belt and then moved to the inner region of the Solar System. Thanks to its (relative) accessibility if compared with the Kuiper belt objects, comet SW1 has been proposed as a potential target for a robotic exploration mission [8].…”

“…-1 -0.5 0 0.5 In fact, the (rather) common assumption that a solar sail should be jettisoned, or the solar sail-induced propulsive acceleration should be neglected, when the solar distance is greater than 5 au, originates from the interesting work by Carl Sauer [13] that analyzes the photonic solar sail performance in a Solar System escape (more precisely, the term used in [13] is 'interstellar') mission scenario. In particular, according to [13], in the last paragraph of p. 9 Sauer substantially affirms that "...the effectiveness of the sail in reducing flight time is minimal..." when the solar distance of the spacecraft is in the range [5,10] au, so that the primary propulsion system (i.e., the solar sail) is jettisoned at 5 au "...to allow the acquisition of science data without possible interference from the sail". This conclusion is, indeed, absolutely acceptable in a Solar System escape trajectory such as that analyzed in the second part of [13], because such a specific trajectory uses a pass close to the Sun (i.e., a sort of 'solar photonic assist maneuver' as named by Leipold and Wagner [14] and Dachwald [15] in their fine paper of 2004) to reach the required value of the hyperbolic excess speed.…”