How to observe an extrasolar planet far from the earth using PC and digital single lens

In order to photograph the stars of the night sky beautifully, we will keep track of the movement of the stars and continue to point the camera "Automatic equatorial mountEquipment called mandatory is essential. We made such an automatic equatorial mount with DIY and further away from the earth in a cheap way to use a commercially available digital single lens cameraExtraterrestrial planetesI succeeded in observingDavid Schneider'S movie is published on YouTube.

DIY Exoplanet Detector - IEEE Spectrum
http://spectrum.ieee.org/geek-life/hands-on/diy-exoplanet-detector

The way that Schneider creates an automatic equatorial mount with DIY is also introduced in the following movies.

How To Detect an Exoplanet with a DSLR - YouTube


"If you have a PC and a digital single lens reflex camera, you can detect extra-solar planets just by preparing some equipment," Schneider said.


Single lens reflex camera set on camera base full of self-made feeling. I am surprised because it can shoot while changing the angle according to the movement of the earth.


The method for detecting the extraterrestrial planet is as follows. A deck like a pumpkin on a shoulder is a star that emits light, and a small pumpkin that you have in your hand is a planet like the earth. Since the planets do not emit light themselves, it is almost impossible to detect them in the usual way.


When the planet revolves around a fixed star, there is a moment when you cross the gap between the star and the earth if the timing matches well. By detecting the change in the light quantity of the star generated at this time, it is possible to confirm the existence of the planet. This methodTransit methodIt is called an exact method that is actually used in NASA and others.


So, I started preparing equipment. By saying that you capture stars in the night sky, shooting with short lenses that many of the most popular users have is insufficient. So, Schneider bought the second used Nikon 300 mm lens which was exhibited on eBay of the auction site at 92 dollars (about 10,000 yen).


But what Schneider has is Canon's "EOS Kiss F(North America name: EOS Rebel XS) ". In order to install Nikon 's lens with cheapness, Schneider bought Nikon - Canon adapter at Amazon for $ 15 (about 1800 yen).


And this is a list of materials for making DIY version automatic equatorial mount.


First of all, there are two pieces of plywood that are likely to be anywhere. In addition to this, wooden parts for the foundation etc appear later though it is not shown in the movie.


And a small block made of aluminum ......


One long stick with threads cut. It is lightly bent, but this shape will become poor.


Two plastic gears that have been pulled out of an inkjet printer that has broken and becomes unusable.


One hinge used for the base of the door and so on.


And although it is a bit altered here, we created a board to control the stepping motor that drives the equatorial mount. My self-made microcomputerArduinoIt is easy to make it if you divert it.


First of all, to prepare the base part, prepare a plywood triangular base. 3 Sumi is equipped with bolts for adjusting the height.


I set a prism on the foundation, but the point is that the top is cut obliquely. This angle is determined according to the latitude of the area where Mr. Schneider lives.


Press the gear removed from the inkjet onto the shaft of the stepping motor. Although a motor is prepared beforehand or a hole is drilled in the board, this may be OK in consideration of Schneider's maniac-like personality.


Hinge the two pieces of plywood with a hinge.


Bolt the control section of the microcomputer etc on the back of one side.


Screw the pan head for fixing the camera ......


Thread the pre-bent screw rod through the hole in the plate and screw it into the hole of the plastic gear.


Here is a cut that seems to be easy to understand. Driving force is generated by the rotation of the gear attached to the screw rod by the rotation of the motor, and the force to open the two boards is applied. It was a mechanism of movement to change the angle of the board with this force and to point the camera according to the movement of the night sky.


If the board is screwed to the Naname part of the prism set in the base, the main body is completed.


The figure of the DIY automatic equatorial mount set in the night sky. It seems that a small battery for automobiles or motorcycles is used for driving the motor.


This time I aimed at "M27 Dumbbell Nebula (Dumbbell-shaped nebula) ", Which is located 63 light-years away from the solar system"HD 189733A stella called. This star is a planet "HD 189733 bIt is known to have a planet, and it is aimed to check the existence of the planet by detecting the change in light that occurs when the planet traverses.


The following graph plots the data obtained by saying that. It was confirmed that the amount of light decreased slightly over about 108 minutes, and the detection of the solar system outside the planet with a digital single lens reflex camera succeeded. In order to eliminate the effects of atmospheric fluctuations and other factors,IrisIt was that I used free software called.


In this way, Schneider succeeded in observing the extraterrestrial planet with a budget of about 200 dollars (about 20,000 yen) without purchasing expensive equipment. Depending on the ingenuity, it may be said that thanks to the development of equipment, it has become possible for anyone to observe such kind of observation.

In addition, even if it is difficult to make your own, since automatic equatorial mounts are released from each manufacturer, people who are interested may try it. Vixen's Portable Equatorial Mount that is convenient to carryStarry Sky Universe Polarie"It is possible to obtain it by Amazon at around 35,000 yen at Amazon.

Amazon.co.jp: Vixen Starry Sky Universe Polariser (WT) 4955295355051: Camera · Video