Uranus in opposition

Press, Volume CXIII, Issue 33189, 31 March 1973, Page 19

Uranus in opposition

April will provide an opportunity, for those with telescopes, to locate the planet Uranus, which comes to opposition on April 11. This distant planet can be found in the constellation Virgo, where it will be slightly north of the midway point between Theta Virginis and the first magnitude stai. Spica. Its magnitude at opposition will be 5.5 and a telescope will show that it is not a star because it will subtend a small disc instead of being a point of light like a star. Pallas, the second asteroid to be discovered, will reach opposition on April 27 Visually it will appear then as a star of seventh magnitude. Its rapid motion across the sky will show that it is an asteroid. On April 1 Pallas will be due north of the faint star Taul Serpentis. Moving quickly across the sky in a north-westerly direction it

■ will be just due south of the - star 45 Bootis on April 30. t Pallas has a diameter of 489 - kilometres and is the second largest asteroid, being ex- . ceeded in size only by Ceres, i Just before dawn during ! the first fortnight of April, Mercury can be seen in the ; morning sky low in the north- . east. It reaches it greatest - elongation west of the Sun - on April 11. Mercury will be t close to the slender waning 1 crescent Moon on the morn- > ing of April 2. Venus will reach superior conjunction on l April 10 and has now disap--1 peared from the morning sky. ' On the morning of April ■ 7, Mars and Jupiter will pro- > vide a striking contrast, just s above the eastern horizon. ' They will then be less than t a degree apart in the con- ; stellation Capricornus. Jupii ter will have a magnitude of t minus 1.7 whilst Mars will be

slof magnitude plus 0.9. In a . telescope the angle subtended 3 by Jupiter will be five and a I half times that of Mars. Both - planets will move eastward . along the ecliptic during the /month but the more rapid motion of Mars will carry it /across a larger arc of the ' sky. This motion will become t apparent if the planets are for a few successive mornings. " Saturn is in Taurus, low in ’lthe early evening sky to the /north west. This month it is too low from our latitudes I for useful observation. "i The recurrent nova, VlOl7 ? Sagittarii, the brightening of which was reported in last II month's notes, has continued •[to increase in brightness very 11 slowly. It has now reached magnitude 10.6 and appears ijto be repeating its behaviour -[during its 1901 outburst -[rather than that of the 1919 fl outburst when it rose rapidly el to seventh magnitude.