Total lunar eclipse on October 8, 2014 in Hanoi – Picture: Hoang Quoc Phuong – HAS
In the early morning of July 28, 2018, Vietnamese and many places around the world will be able to admire an astonishing astronomical phenomenon: a total lunar eclipse. This is the second and last time a lunar eclipse has occurred this year (2018). The previous lunar eclipse occurred on January 31, 2018. HAS organized observations at the clock tower of My Dinh Stadium. The next lunar eclipse that Vietnam will be able to observe will take place on the night of July 16 to 17, 2019 (partial lunar eclipse). The next time we can see a total lunar eclipse will be until July 17, 2019. May 26 However, in 2021, when the total phase occurs, the moon will just start to rise, which is not favorable to observation.
What is a lunar eclipse?
A lunar eclipse is a phenomenon that occurs when the Moon is obscured by the Earth and is not illuminated by the Sun. When the Moon completely enters the Earth’s shadow, a total lunar eclipse is observed.
As the Moon moves deeper into Earth’s shadow, it gradually changes color from silver to orange or red. The cause comes from the earth’s atmosphere. The Earth’s atmosphere, with different densities and temperatures depending on altitude, is like a prism and also contains many dust particles that scatter short-wavelength light, allowing long-wavelength light to to easily pass through (in this case it’s orange red), red is the deviated color. in the dark center of the Earth. When the Moon enters the dark zone, it is actually not completely dark, but this zone is illuminated by red rays, resulting in a dark red Moon that the press often calls a “blood moon.” This phenomenon is physically similar to the fact that the Sun at sunset is red.
The image illustrates the stages and process of a lunar eclipse
II. Area where the lunar eclipse can be observed during the night of July 27 and early morning of July 28, 2018.
During this lunar eclipse, Vietnam is a very convenient place to observe because it is located in a clearly observable area.
The specific events of the lunar eclipse in Vietnam are as follows (according to Vietnamese time UTC+7) in the early morning of July 28:
– The moon enters the darkness: 00:14
However, in the penumbra phase, with the naked eye, it is difficult to see the color change of the Moon.
– Start of the mixing part: 01:24
– Start of full mixing: 02:30
– End of the complete phase: 04:13
– End of partial phase: 05:19
– Moonset: 5:36 a.m.
Choose the most spacious and cool space possible for you and your friends, as far away from the city lights as possible. This is an astronomical phenomenon that can be observed with the naked eye but will be more interesting if you have binoculars or a telescope. The Moon is very large and is therefore easy to locate when observing.
Additionally, I would like to introduce how to make a simple refracting telescope in just a few minutes from available materials to observe the lunar eclipse.
The refracting telescope was built by HAS.
Instructions for taking photos
It is not enough to observe, you may want to save this interesting phenomenon so that you can share it with your friends and everyone. If you already have a camera in hand, it’s extremely simple. Here are some little shares that can help you capture the best photos.
– For phone cameras:
To take photos on your mobile device you need to equip the included telephoto lenses which can be attached directly to the back, this will support the magnification capability of the camera to some extent. Or you can also photograph indirectly using binoculars or a telescope, the resulting image will be quite surprising. If you don’t have support tools, you can always shoot with your bare hands. How to do it as follows: For direct shooting, you need to place the phone on a solid support position or on a tripod, this will help prevent the photo from shaking due to hands and the camera will be able to take photos from very slow speeds without the image. being blurry. You should not use your phone’s zoom mode as it doesn’t solve any problems other than reducing photo details – just take a normal photo and zoom in later in post-production. In this case, choose manual mode. Since the lighting conditions in the full phase are very low, you should reduce the shutter speed as low as possible and gradually increase the speed when the Moon starts to get brighter in the partial phase (the shooting time of view can be calculated). depending on the type of camera, so it is extremely necessary that you keep the camera still while shooting), set the ISO level between 200 and 400 to limit noise. Set white balance in daytime sunlight mode (between 5000-6000k), select manual focus mode to focus most precisely on a very distant object (like a building or a distant light, for example), and whether the camera is capable of it. , shoot in Raw format, which will be ideal for post-production.
– For travel cameras:
Travel cameras have an advantage over phones with their optical zoom capability (3x to 60x depending on type). Set it to fully manual or semi-automatic mode. ISO sensitivity changes flexibly from 100 to 800 depending on the brightness of the moon phases. Place the camera on a flat surface or tripod to shoot at low speed, focus to infinity, and shoot a self-timer after a few seconds. Avoid vibrations caused by hands. Changing the aperture on a travel camera doesn’t make much change, so just let the camera handle it and record Raw files if possible. There are a number of adapters that allow you to attach cameras to binoculars or telescopes. If you want excellent image quality, consider purchasing these for use with a telescope.
+ First set your camera to manual mode (or any mode that allows you to customize settings).
+ Turn off the flash or it will ruin the moonlight!
+ Set to infinite focus mode. In travel cameras, this mode usually takes the form of a landscape mode (Landscape-Landscape) with the symbol SCN or mountain image.
+ Then you need to switch the metering mode to Spot. This helps the image of the Moon to be clear and not explode like a light bulb ^^ Try to find this symbol in your camera!
Finally, point the camera at the Moon and zoom in as much as possible.
To avoid blurry photos due to hand shaking, you should use a tripod. If you don’t have a tripod, you can set the camera to take multiple photos at once to choose the best photo. Now let’s practice taking photos of the Moon so we can capture rare moments of the universe!
– For mirror cameras (DSLR):
It truly is a perfect camera for any subject and the Moon is no exception. There’s nothing better than having a 200-400mm telephoto lens, a sturdy tripod, and a Moon filter (if available). DSLRs are so smart that it is recommended to shoot in Av aperture priority mode. Close your aperture to f8-f11 to ensure sharpness, light will be supported by ISO and speed. You need to turn off noise reduction mode on the camera to get a true-to-life photo, and you may need to subtract some Ev as the scene you intend to photograph will be very different in terms of light , use spot metering mode to let the camera measure best. Turn off anti-shake mode on the lens if you place the camera on a tripod. And of course, shoot in Raw format. Use a soft trigger or delay shooting after 2 seconds to avoid vibration. If you’re stricter, lock the mirror before taking the photo. For DSLRs, there is an advantage that you can not use the camera lens but attach it directly to the telescope, at that time the telescope will become a super telephoto lens with a focal length of 500-1500mm . To do this you need an adapter made from a converted M42 mount and another small part that can be made very easily in a detail shop. Astrophotography will become more professional if you have a tripod with a heliostat function. Take each photo every minute so that when you’re done, you can make a short film of the eclipse process.
I wish you a pleasant observation session!
References: NASA, time and date, Space
Reference article: https://deepsky2000.net/don-xem-ngu…gay-31-1-2018/