Author Topic: Detect exoplanets by yourself with the cheapest equipment  (Read 1398 times)

Offline alfa015

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Hi guys,

I detected my first exoplanet (hd 189733 b) and made a video about it showing step by step how I did it. I thought it could be useful for the people interested in the topic or already starting with transit photometry.

The star has an apparent magnitude of 7.7 and the exoplanet produces a drop of 2.8% during almost 2 hours.

I used a tele-photo lens (the Pentacon 135 mm f 2.8 ), a CMOS camera (ZWO ASI 120 MM) and an equatorial mount (Skywatcher EQ3-2)

I also have a dual-axis motor drive, but a simple one that only controls the right ascension would be enough.

I bought most of the items second-hand from Ebay and I spent around 300 euros.

To set up the tele-photo lens and the camera I have a couple of guide rings and in order to focus the tele-photo lens, I have to separate it 33 mm from the camera by using for example 2 M42 extension rings, one of them 28 mm long and the other one 5 mm.

Now, the steps to detect the exoplanet are the following:

                1. To find out when is the exoplanet going to transit the star with the Exoplanet Transit Database.

                2. With a program called SharpCap, take for example 5-second exposures with a gain of 1 for 3 hours.

                3. Once the transit has finished, with a program called ‘AstroImageJ’ open all the images, select the
                    target star and for example a couple of reference stars, and perform multi-aperture photometry to
                    detect the light curve.

I think it is better explained with a video:

« Last Edit: 10/12/2018 09:07 pm by alfa015 »

Offline alfa015

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Re: Detect exoplanets by yourself with the cheapest equipment
« Reply #1 on: 10/20/2018 12:30 pm »
Anybody interested?

Offline speedevil

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Re: Detect exoplanets by yourself with the cheapest equipment
« Reply #2 on: 10/20/2018 12:36 pm »
Alas, my seeing here is typically terrible (Scotland) - otherwise I would put more effort in.
It is amazing what can be achieved with modest hardware.

Offline programmerdan

Similar -- I desperately want to participate in an effort like this, but my local area is so badly light polluted I can barely use a backyard telescope. I'm still going to make a credible effort to see if it's possible, or if I can get someone nearby to participate.

Thanks for posting this information.

Offline Archibald

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Re: Detect exoplanets by yourself with the cheapest equipment
« Reply #4 on: 10/21/2018 08:32 am »
This is completely awesome. Look at it this way.
I was 13 in 1995, when the first exoplanet was detected. Back then if somebody had said "amator astronomers will someday detect exoplanets" people would have thought "this guy is crazy". That was, what, 23 years ago ? Even ten years ago, when I joined this forum, it would have been considered impossible.

Nowadays you read this. A good amator astronomer, with a 300 euros telescope found on E-bay,can watch for an exoplanet. Blam. You sir, have my respect.

And of course that poor Peter van de Kamp spent his entire lifetime chasing a "ghost" exoplanet around the Barnard star. Decades with his eye glued to his telescope, from the 40's to the 80's. If only he had lived to see this, his mind would be blown. https://en.wikipedia.org/wiki/Peter_van_de_Kamp

Photometry was really one heck of a game changer.
https://www.nasa.gov/mission_pages/kepler/team/william_borucki.html
« Last Edit: 10/21/2018 08:37 am by Archibald »
...you have been found guilty by the elders of the forum of a (imaginary) vendetta against Saint Elon - BLAAASPHEMER !

Offline OxCartMark

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Re: Detect exoplanets by yourself with the cheapest equipment
« Reply #5 on: 02/14/2019 11:41 pm »
This is exceptional.  Thank you for sharing.  I feel like we should be yelling this out to the NSF community for more attention somehow... but how?

Offline Lar

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Re: Detect exoplanets by yourself with the cheapest equipment
« Reply #6 on: 02/15/2019 04:34 am »
I think it's not accurate to say you are "detecting" them. Rather you are confirming the detection. (because the recipe says "start with a known exoplanet with known transit times" ... That's still useful but it's not detection....)
« Last Edit: 02/15/2019 04:37 am by Lar »
"I think it would be great to be born on Earth and to die on Mars. Just hopefully not at the point of impact." -Elon Musk
"We're a little bit like the dog who caught the bus" - Musk after CRS-8 S1 successfully landed on ASDS OCISLY

Offline OxCartMark

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Re: Detect exoplanets by yourself with the cheapest equipment
« Reply #7 on: 02/15/2019 01:07 pm »
I think it's not accurate to say you are "detecting" them.

I disagree.  If I tell you that you can take your boat over to the cove under the bridge and you'll find a lot of fish there then you do take your boat over there and when you get there your sonar sees a school of fish then you will have detected them.  Not discovered them but detected them.

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