Watch this Space for March 2015

Planet Watch Moon Phases The Planets on view this month are: New Moon First Quarter Mercury: not visible this month 20 / 03 / 15 27 / 03 / 15 Venus: mag -3.9 evening star after sunset Full Moon Last Quarter Mars: mag +1.1 in Psc, sets around 20:00 05 / 03 / 15 13 / 03 / 15 Jupiter: mag -2.3 in Cnc, visible all night Saturn: mag +0.5 in Sco rises around 01:00 The Sun Uranus: mag +5.9 in Psc, sets around 21:30 Rises: 06:19, 15th March, Sets: 18:08 Neptune: not visible this month

Constellation of the Month Constellation map credit: IAU and Sky &Telescope magazine —Part 1 (cropped) Orion is an ancient constellation with many associated myths. For a good summary see http://www.ianridpath.com/startales/orion.htm. Notable stars:  Ori - . M2 red supergiant. Mass 8-20, radius 950-1200, distance 643 ly. Uncertainties are due to variability and extended atmosphere. Magnitude 0.2 (1933 & 1942) to 1.2 (1927 & 1941).  Ori - . B8 blue-white supergiant. Mass 21, radius 80, distance 773 ly. Magnitude 0.05-0.18 due to irregular pulsations.  Ori - . B2 blue-white giant, one of the hottest stars visible to the naked eye. Used to be a magnitude standard but now known to be slightly variable (mag 1.59-1.64).  Ori - The “Belt Stars”, , , . O9 blue supergiant, O9 blue supergiant and B0 blue giant respectively. These three stars form part of the Orion OB1 Association. See http://en.wikipedia.org/wiki/Orion_OB1_Association.  Ori - Multiple star forming the “Trapezium” in, and illuminating, the M42.  Ori - Meissa. Multiple star system with a very hot O8 giant, centre of a huge ring of gas and dust 150ly across called, aptly(!), the Lambda Orionis Ring, catalogued by Sharpless as Sh2-264.  Ori - Multiple star system which illuminates IC434, the red hydrogen emission nebula behind Barnard 33, the “Horsehead Nebula”.

Lunar Feature of the Month Crozier To find this crater first come to the Mare Fecunditatis and then drop down to the Maria’s south western edge, if needs be you can use the prominent crater Colombo to guide you to the correct area. Crozier is a crater that was formed during the imbrian period of lunar history (3.8 to 3.2 Billion Years ago) Crozier has a very distorted rim and appears to exhibit bulges at the Northwest, southeast and southwest edges. The bowl of the crater has nearly filled with basaltic lava which in turn means the crater has a very low surface brightness (albedo) so therefore the best viewing times for this particular crater are 4 days after the new moon or 3 days following the full moon.

Crozier 2005 September 21 23:45—00:15 UT 200mm SCT x 200 Drawing by Peter Grego Birmingham, UK

The Sun in February

The Sun seems to be entering a quiet phase at the moment with very few sunspots by the end of the month. However, solar wind from coronal holes has produced aurorae as far south as Montana, USA. (47⁰N).

Credit: Harald Albrigtsen. Tromsø, Norway Green Flash: Mila Zinkova 29/01/15 @ San Francisco, California, USA Aurora: Philip Granrud. Flathead Valley, Montana .

THE GREEN FLASH: The Californian coast is a world top spot for green flashes. Air is cooled by the cold offshore current and, topped by warmer air from inland, provides the ideal temperature profile for flashes. This flash might be something extra special - a 'cloud-top’ flash. These are seen as the sun's rays graze a distant cloud bank. Marine stratus can be trapped by temperature inversion layers which could generate some of the flashes. But that is not always the case and there is much unexplained about them. (Source: Space Weather).

IMPORTANT SPACE WEATHER SATELLITE LAUNCH: On February 11th NOAA, NASA and the US Air Force launched a satellite that is critical to space weather forecasting. The Deep Space Climate Observatory (DSCOVR) will monitor the solar wind from the L1 point, 1.6 million km. upstream from Earth. DSCOVR will replace the aging ACE spacecraft in providing early warnings of incoming CMEs and other solar storms. (Source: Space Weather).

ISS and Iridium Flares this month

Satellite flares Magnitude greater than -4.0, height greater than 30°

Date Time Satellite Mag Dirn Ht ISS visibility Tue 10 Mar 18:44 Iridium 57 -6.2 SSE 58° ISS night-time visibility, Wed 11 Mar 18:38 Iridium 60 -4.6 SSE 58° magnitude greater than –2.0, height greater than 30° Sat 14 Mar 20:05 Iridium 96 -7.1 ESE 51° No evening passes Sun 15 Mar 18:23 Iridium 95 -6.8 S 59° Mon 16 Mar 18:17 Iridium 30 -4.0 S 59° Satellite events Wed 18 Mar 20:38 Metop A -4.0 ESE 68° Transits of Sun and Moon longer than 1s, and night- Thu 19 Mar 19:44 Iridium 35 -7.2 ESE 57° time close passes. Fri 20 Mar 18:02 Iridium 91 -7.3 SSW 58° Tue 24 Mar 19:22 Iridium 8 -7.4 SE 63° Date Time Event Wed 25 Mar 20:52 Iridium 86 -5.8 ENE 41° Wed 4 Mar 14:17 Anik E1 Ark transit of Sun Sun 29 Mar 20:01 Iridium 34 -5.3 SE 67° Tue 5 Mar 10:29 Anik E1 Ark transit of Sun

Data from CalSky: http://www.calsky.com