Most launch vehicles place geostationary satellites directly into a geostationary transfer orbit (GTO), an elliptical orbit with an apogee at GEO height and a low perigee. On-board satellite propulsion is then used to raise the perigee, circularise and reach GEO.
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GJ 436 b's orbit is likely misaligned with its star's rotation. In addition the planet's orbit is eccentric. Because tidal forces would tend to circularise the orbit of the planet on short timescales, this suggested that Gliese 436 b is being perturbed by an additional planet orbiting the star.
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This family includes both microviridins and marinostatins. It seems likely that in both cases it is the C-terminus which becomes the active inhibitor after post-translational modifications of the full length, pre- peptide. It is the ester linkages within the key, 12-residue region that circularise the molecule giving it its inhibitory conformation.
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HAT-P-1b is located in a very close orbit to its star, taking only 4.47 days to complete. It therefore falls into the category of hot Jupiters. At only 8.27 million kilometers from the star, tidal forces would circularise the orbit unless another perturbing body exists in the system. At the present time, the existing measurements are not sufficient to determine the orbital eccentricity, so a perfectly circular orbit has been assumed by the discoverers.
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They were equipped with an SVM-1 apogee motor to circularise their orbits following launch atop Delta E1 carrier rockets. All four satellites were launched from Launch Complex 17B at the Cape Kennedy Air Station. Each satellite had a mass at launch of , which decreased to around once the satellite had fired its apogee motor and manoeuvred into its orbital position. Intelsat II spacecraft were designed to be operated in geostationary orbit; however the first satellite's apogee motor malfunctioned leaving it in a lower than planned orbit.
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Most launch vehicles place geosynchronous satellites directly into a geosynchronous transfer orbit (GTO), an elliptical orbit with an apogee at GSO height and a low perigee. On-board satellite propulsion is then used to raise the perigee, circularise and reach GSO. Once in a viable geostationary orbit, spacecraft can change their longitudinal position by adjusting their semi-major axis such that the new period is shorter or longer than a sidereal day, in order to effect an apparent "drift" Eastward or Westward, respectively. Once at the desired longitude, the spacecraft's period is restored to geosynchronous.
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P1 phage had been discovered in 1951, but was little understood when Sternberg began to research the virus. He discovered the Cre–lox site-specific recombination system, in which the Cre recombinase enzyme acts at the lox recombination site to allow P1's double- stranded DNA genome to circularise after infection. Sternberg, Brian Sauer and others in his group subsequently showed that Cre–lox is a flexible recombination system which also functions in eukaryotic cells, and it is now widely used in genetic engineering. Sternberg elucidated multiple other features of the phage and its life cycle, including lytic and lysogenic replication cyles, DNA methylation and viral packaging, as well as immunity to the phage.
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Operation had started in June 1810, but weighing machines were not yet properly provided; the Company's power to charge tolls required the provision of weighing machines, and in their absence no tolls could legally be levied, so that much of the traffic travelled free at first. Dissatisfaction with the quality of the contractor's work continued to be expressed, and some track needed to be relaid at an early date. A third Act of Parliament was secured on 26 June 1811 authorised a further extension of the capital, of £35,000. On 16 March 1813 a directors’ meeting was held at which it was determined to circularise the shareholders: > “The water was let into the canal and basin this day, and the railways being > in a state of work, the undertaking may be considered as complete.” However the dominant purpose of the meeting was to follow: > “A considerable debt has been incurred, to liquidate which, the sum of > £10,000 must be immediately raised.” If this was an invitation for someone to make a donation, it was in vain, and a fourth Act was obtained in May 1814 authorising a further increase in capital of £30,000.
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