Radio Astronomy

Perseids meteor shower August12/13 (Radio Observations)

A little after the event, but has taken time downloading / checking data after my eclipse chasing.


 

 

 

 

 

 

 

 

 

 

 

 

 

 

The daily rate shows a peak on the 12th August, however checking out the hourly rate shows the maximum hourly rate occurred on the 13th August at during 7 – 8 am with a max of 30 meteors. The maximum activity on each day was concentrated in the pre dawn hours.


 

 

 

 

 

 

 

 

 

 

 

 

 

 

I noticed the odd perseid in the USA but being a lot further south the radiant was a lot lower in the sky, quite close to horizon, which made life difficult when dark spots were usually surrounded by trees! With early starts each day it wasn’t feasible to wait into the early hours.

Below is data on rest of showers during August, September offers only minor showers.

 

Major Activity:

Radiant Duration Maximum
Perseids (PER) July 23-August 22 Aug. 12/13

Moderate Activity

Radiant Duration Maximum
Northern Iota Aquarids (NIA) August 11-September 10 Aug. 25/26
Southern Iota Aquarids (SIA) July 1-September 18 Aug. 6/7
Alpha Capricornids (CAP) July 15-September 11 Aug. 1/2
Northern Delta Aquarids (NDA) July 16-Sepember 10 Aug. 13/14
Kappa Cygnids (KCG) July 26-September 1 Aug. 18

Minor Activity

Radiant Duration Maximum
August Eridanids August 2-27 Aug. 11/12
Upsilon Pegasids July 25-August 19 Aug. 8/9
Alpha Ursa Majorids August 9-30 Aug. 13/14

Daylight Activity

Radiant Duration Maximum
Gamma Leonids August 14-September 12 Aug. 25/26

 

Clear Skies

Pete Hill

Radio scatter of July Meteors

Here is the July meteor data based upon radar backscatter from Graves. As commented by http://meteorshowersonline.com/july_radiants.html

“Although the July radiants do not individually produce strong rates, activity from the Aquarius and Capricornus regions in July and early August, as well as minor activity from other radiants, cause hourly rates to basically rise between the middle and end of July for observers in both the Northern and Southern Hemispheres. Therefore, clear, moonless nights can be quite enjoyable for anyone observing during late July. “

there is a definite increase in activity towards end of month, where we are also entering the Perseid stream ( July 23 – Aug 22nd) and there has been a noticeable increase in fireballs picked up by NASA all sky monitors ( see Spaceweather.com)

Moderate Activity:

Radiant Duration Maximum
Southern Delta Aquarids (SDA) July 14-August 18 July 28/29

Minor Activity:

Radiant Duration Maximum
Alpha Lyrids July 9-20 Jul. 14/15
July Phoenicids (PHE) July 9-17 Jul. 14/15
Alpha Pisces Australids July 16-August 13 Jul. 30/31
Sigma Capricornids June 18-July 30 Jul. 10-20
Tau Capricornids June 2?-July 29 Jul. 12/13
Omicron Draconids July 6-28 Jul. 17/18

 

I have also combined last years daily counts with this years for comparison:

although the count rates vary, there is some mirroring of variation early in the month, but there appears to be an increase rather than decrease in activity during the latter stages of the month. Notice also the diurnal nature of activity, particularly during the second half of the month, where activity is very high during the early hours of the day ( see Hourly meteor rate) .This is a good pointer to observing the Perseids later this month, with peak activity from midnight , through the early hours of the 12-13 Aug, a waning Gibbous moon will be rising around midnight which might interfere with viewing, but it stays relatively low in the sky as the Perseid radiant climbs higher. The shower is active from July 23 till Aug 22nd with best views during the nights of the 11, 12 and 13 Aug. Definitely worth getting those all sky cameras we have made up and running to record shower activity.

clear skies

 

Pete H

June Meteor Data

Hi

below is the daily and hourly rates of meteor detection using Graves radar signal, no major showers this month, month started with continued high count from end of May, then varied with combination over various showers overlapping during month, possible Graves “down time ” early in the month, from morning of 2ndJune to morning 3rd June.

Moderate Activity

Radiant Duration Maximum
June Lyrids June 10-21 Jun. 15/16

Minor Activity

Radiant Duration Maximum
June Aquilids June 2-July 2 Jun. 16/17
June Boötids June 27-July 5 Jun. 28/29
Corvids June 25-July 3 Jun. 27/28
Tau Herculids May 19-June 19 Jun. 9/10
Ophiuchids May 19-July 2 Jun. 20/21
Theta Ophiuchids May 21-June 16 Jun. 10/11
Sagittariids June 10-16 Jun. 10/11
Phi Sagittariids June 1-July 15 Jun. 18/19
Chi Scorpiids May 6-July 2 May 28-Jun. 5
Omega Scorpiids May 19-July 11 Jun. 3-6
June Scutids June 2-July 29 Jun. 27/28

Daylight Activity

Radiant Duration Maximum
Arietids May 22-July 2 Jun. 7/8
Zeta Perseids May 20-July 5 Jun. 13/14
Beta Taurids June 5-July 18 Jun. 29/30

Meteor detection over April & May 2017

April: the Lyrids towards end of month were just noticeable, with varying activity from minor showers overlapping over the month.


 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Major Activity:

Radiant Duration Maximum
Lyrids (LYR) April 16-25 Apr. 22

Minor Activity

Radiant Duration Maximum
Tau Draconids March 13-April 17 Mar. 31-Apr. 2
Librids March 11-May 5 Apr. 17/18
Delta Pavonids March 21-April 8 Apr. 5/6
Pi Puppids (PPU) April 18-25 Apr. 23/24
April Ursids March 18-May 9 Apr. 19/20
Alpha Virginids March 10-May 6 Apr. 7-18
April Virginids April 1-16 Apr. 7/8
Gamma Virginids April 5-21 Apr. 14/15

Daylight Activity

Radiant Duration Maximum
April Piscids April 8-29 Apr. 20/21

 

 

May started with a continuation of the lower activity detected at end of April, before the marked increase due to the Eta Aquarids, there was a noticeable increase in activity over the rest of the month with activity from minor showers overlapping and the activity of the day time showers showing up prominently on the hourly recording, greater activity before midday on most days.


 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Major Activity:

Radiant Duration Maximum
Eta Aquarids (ETA) April 21-May 12 May 5/6

 

Minor Activity

Radiant Duration Maximum
Epsilon Aquilids May 4-27 May17/18
May Librids May 1-9 May 6/7
Eta Lyrids May 3-12 May 8-10
Northern May Ophiuchids April 8-June 16 May 18/19
Southern May Ophiuchids April 21-June 4 May 13-18

 

Daylight Activity

Radiant Duration Maximum
Epsilon Arietids April 25-May 27 May 9/10
May Arietids May 4-June 6 May 16/17
Omicron Cetids May 7-June 9 May 14-25
May Piscids May 4-27 May 12/13

It will be interesting to see if any of the radar detections can be matched visually once I’ve got the all sky camera up and running, I will be running Dimension4 to synchronise times on both machines, enabling a match to be made to visual and radar sightings.

Look out for the June Lyrids 15-16 June, although just after full moon and the nights will be a lot shorter.

First successful detection of meteors by radio scatter using FunCube Dongle Pro Plus Software-Defined Radio @ LRO

Success at last!

In spite of all the positive posts around meteor radio scatter I have posted recently, one thing I had not managed to do was to use my FunCube Dongle Pro Plus software defined radio – this has been my aim as I do not wish to leave my (expensive) Yaesu FT-817 turned on and plugged in long term.

Today, is the first time I have managed to that using Dell E6400 laptop, Spectrum Lab software, USB 1 extension cable, FunCube Dongle Pro Plus, Bill Watson’s feeder cable, Bill Watson’s Slim Jim aerial tuned to 143.049MHz on 4 poles mast outside log cabin at LRO (4 old trampoline steel poles – total height 4-5m).

The following link gives an account of my success and suprising failure with same setup using rear mounted Moxon tuned to 2m band (rich text file):

Radio Observing Log Dell E6400 010517@0907

Configuration file used on Spectrum Lab for above detections:

Meteor Detection 2017-05-01@0838(Dell E6400) (this is a ZIP file – WordPress will not allow the extension to be attached to this entry without being zipped first – to use this unzip the file and save the configuration file in your Spectrum Lab configuration folder).

This successful use of the FunCube Dongle Pro Plus occurred with both FunCube Dongle Pro Plus and Yaesu tuned to 149.049MHz. I used SDR Sharp to set upper side band on FunCube and Yaesu also on upper side band.

Andy

Meteors detected using above setup between 08:27 & 09:17 (gives idea of frequency and how successful this has been):

 

My best detections of meteors ever by radio scatter at Rosliston Forestry Centre Science Event 29/4/2017

During the science day, the RAG team helped my erect a 4.8m ex-military aerial (purchased from ebay few years ago for around £30) – I attached to the top of this Bill Watson’s homemade Slim-Jim aerial, purpose-cut for 143.049MHz. Using my Yaesu FT-817 radio, I set about trying to detect meteors from Graves radar in France by radio scatter at 143.049MHz upper side band and……….

My best detections ever!! The meteors were coming thick and fast – sometimes 3 on the screen at any one time on Spectrum Lab! I have NEVER detected meteors so well as I did today. A true WOW! moment.

Below are pictures from the event and some examples of meteors detected (WSJT-10 and Spectrum Lab software screenshots) – a more comprehensive account of meteors detected can be found in PDF format by clicking of this link: Meteor detection screenshots 290417

Andy

Photos of the event:

Photos of meteors detected during the day at the forestry centre using the radio and aerial above:

The following screenshot from Spectrum Lab shows the carrier from Graves (usually not seen but atmospheric conditions today meant it was intermittently visible) and two meteors (showing offset between meteors and the carrier of around 200Hz)

The screenshot below shows that the carrier is usually not seen. In addition, these meteors have spread on the frequency axis – indicating doppler shift in speed in components of the meteor (slightly different speeds of travel)

Other good examples of meteors on Spectrum Lab screenshots:

Meteors were also shown on WSJT-10 software waterfall traces – each time a meteor appeared on either WSJT-10 (below – the peaks on green trace + coloured spot above it – see for example second line on screenshot below where four meteors are shown) an audible ping could be heard from the laptop speakers.

Interpretation of above WSJT-10 screenshot:

Other good examples of WSJT-10 meteor detections (these would have simultaneously been seen on Spectrum Lab on 3D chart):

  

New Moxon aerial for meteor radio scatter

From: bill Watson [mailto:bill.g4eht@yahoo.co.uk]
Sent: 27 April 2017 17:31
To: Thornett Andrew (05Y) Walsall CCG
Subject:

 

HI ANDY

WE HAVE……………GOOD NEWS…….AND………BETTER NEWS. !

I HAVE TESTED THE 2 MTR MOXON…….IT IS FINE…..ABSOLUTELY NOTHING WRONG WITH IT……ITS BANG ON RESONANCE…..NO PROBLEMS. I TRIED MOUNTING IT VERTICALLY THOUGH………….NO CHANCE. !! HAVING THE POLE BETWEEN THE 2 ELEMENTS IS A……NONE STARTER. – SENDS IT WAY OFF RESONANCE, AND THE SWR GOES THROUGH THE ROOF. !

MOUNTING IT VERTICALLY WOULD MEAN USING A …NONE METALIC SUPPORT AT THE TOP SECTION…..AS I POINTED OUT. SO……I SET ABOUT MAKING YOU ANOTHER ONE ANDY. THIS ONE, I HAVE DESIGNED DIFFERENTLY……ITS MOUNTING POSITION IS DESIGNED TO FIT AT THE BACK OF THE REFLECTOR, AND NOT IN THE MIDDLE OF THE 2 ELEMENTS.

WHEN DESIGNING THEM LIKE THIS, YOU ALWAYS HAVE TO MAKE SURE THAT THE DISTANCE BETWEEN THE REFLECTOR AND THE MOUNTING POLE IS STILL NOT TOO CLOSE. !    A SIMILAR DISTANCE BETWEEN THE 2 ELEMENTS ID USUALLY SUFFICIENT….SO THATS HOW IT IS BUILT. I HAVE RESONATED IT AGAIN, SO THAT IT IS USABLE FOR 2 MTRS……IT CAN NOW BE USED EITHER VERTICAL/HORIZONTAL VERY EASILY WITHOUT BOTHERING ABOUT THE TOP POLE NOT BEING MADE OF METAL. I HAVE ALSO TREID USING IT FOR YOUR ‘METEOR RECEPTION’…….BRILLIANT. !

I MOUNTED IT VERTICAL FOR THIS TEST OF COURSE, HOWEVER I HAVE HAD ANOTHER THOUGHT. YOU PROBABLY HAVENT HEARD OF THIS ANDY – SLANT POLARIZATION. THIS MOXON, YOU CAN NOW EASILY…………SLANT POLARIZE…..IF YOU WISH. BY DOING THIS, IT’S POSSIBLE TO ( IF YOU LIKE ) GET THE ‘BEST OF BOTH WORLDS’. A BIT OF VERTICAL…………. A BIT OF HORIZONTAL………WHICH, IF YOU THINK ABOUT IT, MAY WELL E BETTER FOR YOUR METEOR DETECTION. FOOD FOR THOUGHT.?

ANYHOW……ITS UP TO YOU, TO USE IS IT, AND MOUNT IT AS YOU WISH. WHAT YOU MAY OF COURSE FIND, IS THAT AS YOU WILL NOW HAVE THE CAPABILITY OF EXTRA GAIN DUE TO IT BEING DIRECTIONAL  ( UNLIKE THE 5/8 VERTICAL )  AND BEING ABLE TO MOUNT IT VERTICAL AND BEAM SOUTH EAST, THEN IT COULD OUT PERFORM THE 5/8 WAVE. !!!!!!!!!!!!

HOWEVER…..IT WONT LOOK AS ‘NEAT’ AS THE 5/8  FOR YOUR XYL AND NEIGHBOURS. !

ANYHOW………ONCE AGAIN…ALL VERY WELL MADE AND SET UP, AND FOR CERTAIN IT WILL MAKE YOU A EXCELLENT PORTABLE AERIAL ANDY.

LET ME KNOW WHEN YOU CAN PICK IT UP, OR I CAN EASILY DROP IT OFF FOR YOU WHEN YOU ARE IN.

BYE FOR NOW

Vy 73……………..de……………….Bill…………..G4EHT

Further success recording meteors at LRO by radio scatter 22-23/4/2017 (Lyrid meteor shower)

The combination of our Yaesu FT-817 radio, high quality feeder cable and Bill Watson’s carefully hand-made 5/8 vertical aerial (made to be resonant at 149.049MHz) at 2.4m height (top of log cabin – neighbour politics mean I can’t have it higher) has led to great success detecting meteors by radio scatter during this Lyrid meteor shower – the best detection rates we have ever had in Lichfield. This demonstrates the importance of using a sensitive modern radio and a resonant aerial when detecting meteors.

I have also spent today trying to get FunCube Dongle Pro Plus working – without success!! I need help with this!

We proved that 143.049MHz Upper Side Band (on Yaesu appears as 143.049.00 R MHz USB) is a good frequency to detect meteors, the carrier for Graves appears intermittently and then goes again, when it does appear it varies up and down consistent with pulses from the radar, and that a resonant aerial is required.

Andy

Best screenshots from the Lyrid Meteor Shower 20-23/4/2017:

 

Following shows 2 typical meteor peaks but also shows Graves carrier which is usually not seen – meteor frequency is offset from the carrier.

2 meteors – these are probably 2 fragments of same meteor coming in one after the other:

Large rolling meteor – up and down with time as surface area increases and decreases with roll of meteor (below):

3 successive meteors:

                

Meteor below shows variation on frequency axis – this is due to multiple fragments together travelling at slightly different speeds – Doppler effect changes frequency:

Excellent example below of large rolling meteor:

     

Screenshots below show the 3D Spectrum Lab screenshot and also the WSJT-10 waterfall – this shows the ping that is seen and also heard if the computer’s speakers are turned on (audible ping not recorded here):