Abstract ID - Th1-P009 ATMOSPHERIC AEROSOLS AND DIFFERENT TYPES OF METEOR SHOWERS Ajinkya Kakade, Sumedh Mane, Pratibha Mane. Department of Physics, Fergusson College, Pune-411 004, Maharashtra state, India Introduction Medium Level Meteor Shower Low Level Meteor Shower Atmospheric aerosols are minute particles (10-9 to 10-4 m) suspended Zenith Hour Rate - Between 2 to 10 Meteors. Zenith Hour Rate - Less Than And Equal To 2 Meteors. in various layers of earth’s atmosphere. During meteor showers, huge Meteor Shower Date Peak Dates amount of cosmic debris called meteoroids enters into the Earth’s Alpha Centaurids (7th Feb 2009) Alpha Centaurids (8th Feb 2011) atmosphere. These particles contributes to aerosols in the Delta Velids Jan 22 –Feb 21(2009) 5 February 2009 mesosphere. An attempt is made to study correlation between the Beta Herculids Feb 10 -Feb 14(2011) 13 February 2011 mesospheric Aerosol Number Density in per dm3 (AND) and Meteor Gamma Normids Feb 25 -March 13(2011) 13 March 2011 Showers of medium-level (ZHR in between 2-10) and meteor Delta Velids Beta Herculids 160 E13/02/11 160 M14/02/11 showers of low-level (ZHR˂2) also. The observations were carried M14/02/11 M15/02/11 out at tropical station Kolhapur (16°42′N, 74°14′E) during the period 140 140 1 January 2009 to 31 December 2011. 120 120 100 100 M14/02/11 160 M15/02/11 Altitude (Km) Altitude th th 140 CBE: Coma Berenicids (20 Dec 2009) CBE: Coma Berenicids (20 Dec 2010) 80 (Km) Altitude 80 120 100 60 60 Altitude (Km) Altitude 80 40 40 60 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 40 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 AND AND AND 160 160 E13/02/11 160160 M14/02/11E13/02/11M15/02/11 160 M14/02/11 M 15/02/11 E15/02/11 E15/02/11 M14/02/11 M15/02/11M14/02/11 M15/02/11 160 140 140 140140140 140 120 100 120120 120 120 120 Altitude (Km) 80 60 100100 100 100 100 M14/02/11 M14/02/11 40 160 M15/02/11 160 M15/02/11 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 Altitude (Km) Altitude Altitude (Km) Altitude AND 140 140 Altitude (Km) Altitude 80 (Km) Altitude 80 (Km) Altitude 8080 80 120 120 100 100 th 60 606060 60 Altitude (Km) Altitude Alpha Crucids (15 Jan 2009) (Km) Altitude Delta Cancrids (17 Jan 2009) 80 80 60 40 404040 40 60 0.10.1 0.20.2 0.30.3 0.40.4 0.5 0.6 0.7 0.80.8 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 E04/02/09 0.1 0.2 0.3 0.4 0.5 M05/02/090.6 0.7 0.8 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 40 40 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 M05/02/09 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 100 100 M06/02/09 AND AND AND AND AND AND Methodology 160 160 M15/02/11 M15/02/11 M 15/02/11 M 15/02/11 E15/02/11 160 E15/02/11 E15/02/11 160 E15/02/11 140 140 140 140 80 80 Basic Principle 120 120 100 120 100 120 Altitude (Km) Altitude (Km) 80 • Sun is within 0-18º below the horizon. 80 60 60 Altitude (Km) (Km) (Km) Altitude Altitude Altitude Altitude (Km) Altitude 100 Altitude (Km) (Km) (Km) Altitude Altitude Altitude Altitude (Km) Altitude 100 60 60 40 • 40 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 The solar radiation scans the Earth’s atmosphere during the 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 AND AND Altitude (Km) Altitude 80 enhancement of the twilight. (Km) Altitude 80 60 60 • Light received from any part of the sky is primarily due to the light 40 40 AND 0.1 0.2 0.3 0.4 0.5 0.6 0.7 40 40 AND scattered by the illuminated molecules and the particles of interest. th 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 PUP : Puppid /Velids (7th Dec 2011) COM: Coma Berenicids (29 Dec 2010) 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 M06/02/09 AND AND E06/02/09 E06/02/09 • The height of this lowest layer called twilight layer, increases with 100 100 E07/02/09 increasing earth's shadow height. Gamma Normids • Scattered light comes more and more from the higher altitudes 80 80 Altitude (Km) (Km) (Km) (Km) Altitude Altitude Altitude Altitude Altitude (Km) (Km) (Km) (Km) Altitude Altitude Altitude Altitude 60 60 40 40 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.1 0.2 0.3 0.4 0.5 0.6 0.7 AND AND Observations and Results Observations and Results Meteors Observations • In title of graphs we see the peak dates of respective meteor showers. On the Delta • Increased in AND observed in the morning of peak date • Measured time ‘t’ in terms of ‘seconds’ and intensity ‘I’ in terms of peak dates or just after the peak dates we get to see the increment in AND Velids from height of 70-90 km and slightly increased till the ‘volts’. starting with higher altitudes and then later in lower altitudes. morning of next day. • Observation time converted to solar zenith angle Z. • There are specific number of AND at respective altitudes which are not altered • AND decreased on next day of peak dates. Aerosols • unless such events occur. So before and after meteor showers we can see the The vertical height ‘h’ from the surface of the earth, of a point where settled at height of 40-50 km. normal distribution of AND w.r.t. altitudes. the solar ray grazing the surface of the earth meets the line of slight. • Overall increased in AND observed in the range of 50-100 • Frist two figures indicates the graphical interpretation of AND distribution just • ‘R’ is radius of earth and ‘δ’ is sun's depression 푝푎푟푡푖푐푙푒/푑푚3. before, after and on the day of Alpha Centaurids of year 2009 and 2011. In Earth’s Shadow Height both the graphs we see red curve is shifted slightly whereas blue and green Beta • Increased in AND observed after the peak date from curves coincides. Which indicates the AND increases just after the Meteor Herculids height of 50-160 km and remained almost same for a day. • The sun sinks below the horizon, the Shower and regains the original value. • Some aerosols came down by height of 6km in 24 • CBE ‘s data of 2009 is limited up to 80 km altitude due to lack of data. In hr.(108km to 102km) and also increased by almost 55 h= R sec( ) − 1 effective height of the Earth’s shadow 3 3 푝푎푟푡푖푐푙푒/푑푚 on 15/02/11. rises and scattering takes place to higher 2009 at 78 km altitude AND increases from 350 to 500 particles per dm (ppd) • Above 60km aerosols came to normal as they were before levels. and at same altitude for 2010 AND increases from 380 to 480 ppd. • Alpha Crucids and Delta Cancrids occur just one after another. At altitude of peak. Some aerosol settled on 91 km and 81 km (observed 1 dI d In I • Light received at the ground will be the by peaks). − = − primary scattered light by the particles of 80 km due to Alpha Crucids 2009 AND increased from 250 to 325 ppd and I dh dh due to Delta Cancrids 2009 AND increased from 275 to 350 ppd. Here we see • Overall increased in AND observed in the range of 50- interest 3 collective effect of both the Meteor Showers. 100 푝푎푟푡푖푐푙푒/푑푚 . • Variations in the vertical profiles 1 dI dIn (aerosol number density) • The intersection of blue and red curve in PUP indicates aerosols were just − = − of the molecular density were Gamma • Increased in AND observed by 3 times. I dH dh introduced in atmosphere at higher altitude. Below the crossing red curve very small and their effect on the shows normal AND while blue curve shows AND travelled down as the time Normids • 70-150 km on M 12/03/11 and 60-150 km on observed is constant. passes. M 13/03/11 and 50-150 km on M 16/03/11. • COM shows the distribution of AND before and after the event. Where we • Overall increased in AND observed in the range of 50- Aerosol Number Density/ cm3 = Antilog10 {10[1/I (dI/dh)]-1} get to see red curve is distinctly shifted to right. 150 푝푎푟푡푖푐푙푒/푑푚3. Instrument Conclusions Block Diagram Semiautomatic Twilight ➢Aerosol particles are evenly distributed along the altitude of range 50 km to ➢Most of these suspended particles starts moving downwards which Of Instrument Photometer 150 km (Mesosphere and Thermosphere). causes increase in AND at lower altitudes.