What technique do astronauts use to photograph the Earth, the Moon and distant galaxies? How does the telescope see? What happens to Earth cameras in space? Why there are cameras on the moon and other interesting facts about space photography – let’s figure it out together.
Astronauts are avid photographers. They photograph planets, the moon, outer space, galaxies and stars. In space, the range of surveys is much wider than on Earth. Therefore, the technology used is very different – from radio telescopes to conventional film cameras . And if you think that only special devices are used in space, then you are mistaken. For the sake of stability and trouble-free operation, they can be as simple as three kopecks, and sometimes even lag behind what astronomers use on earth.
The first and main task of space exploration is to observe our planet, conduct experiments and study the distant corners of the universe. Therefore, the specialized equipment is very different from the photographic equipment to which we are accustomed.
There are many artificial satellites orbiting the Earth, including automatic systems that observe very distant objects. For example, the automatic observatory “Hubble”.
The Hubble telescope is remarkably similar to the Pringles.
A super-powerful telescope can see at a distance of billions of kilometers. Although a kilometer in space is the same as a micron on earth. Long distances are measured in light years – the Hubble telescope can zoom in on objects at a distance of 1,600 light years. Do you know how many kilometers are in one light year? Nine trillion four hundred sixty billion seven hundred thirty million four hundred seventy two thousand five hundred eighty point eight. And now we multiply this “small” figure by 1600 and look at the distant galaxy in full growth:
Left – image from an amateur telescope, right – from the space Hubble. If this is not enough and you want to consider the three brightest stars in the Orion Nebula, then please: even closer, even brighter! Ground-based telescopes are not taught this. The atmospheric layer interferes.The technical characteristics of the Hubble will impress anyone. For contrast, let’s compare with it civilian super-strong optics. The largest telephoto lens a home photographer can afford is a 600mm lens . A kind of portable telescope:
Of course, there are more lenses, but these are extreme focal lengths, such devices are far from compact and cost a fortune. Nevertheless, this “telephoto” will allow you to view the moon on a fairly large scale:
This is how an SLR camera sees the moon through a lens with a focal length of 600 mm.
Now attention: the focal length of the Hubble is 57.6 meters! Meters, not millimeters! That’s 57,600 millimeters – 96 times that of a telephoto lens. At the same time, the resolution of the images is 10 times higher in the telescope. This means that, on the same scale, Hubble will allow the entire system of galaxies to be viewed practically “stellar”. The photo weighs over 10 GB. In the original, it can be seen on a special website .
265 thousand galaxies on your home monitor are now reality.
The telescope was launched 30 years ago. During this time, scientists pulled up physics and created new advanced systems for observing distant objects. Now even atmospheric distortion does not affect image quality as much as it did when Hubble was launched. Therefore, the legendary giant is already significantly inferior to modern equipment in terms of the quality of photographing close objects:
VLT ground observatory vs Hubble space observatory.
There is an explanation: space observatory designed to capture ultra-large objects, which emit only a weak infrared and ultraviolet spectra, rather than reflecting a bright sunny light . Such a signal can be ten billion times weaker than the human eye can see. And Hubble sees even more:
The principle of operation of a telescope is almost the same as that of a camera and a lens . To observe the distant expanses of the universe, telescopes scan the radiation. These can be long and short light waves of various spectra.
An illustrative diagram of a photo lens – spherical and aspherical lenses guide photons of light to the camera matrix. In this case, the light power decreases with each passage through the optical element. For a telescope with a long focal length, such losses are unacceptable.
Instead of a system of several lenses in a conventional photographic lens or an amateur refractor telescope, mirror telescopes and large observatories use one huge or many concave mirrors that form a reflective area and focus light at one point with little or no loss of quality.
Such an image cannot be obtained using civilian equipment: each optical element of the system introduces its own distortions, aberrations, and reduces the flux of photons that must hit the light-sensitive surface. In the technology of the “space” scale, these defects are minimized by systems of stabilization and dynamic change in the shape of the mirrors.
The effect of turning on the adaptive mirror adjustment system is equivalent to the one as if the telescope was outside the atmosphere, where surface vibrations do not distort space. Here’s how it changes the picture:
Ground observatory MAGIC.
The size of the reflective surface is responsible for the quality of the final image. For example, the Hubble telescope, which will go on a well-deserved rest in 2030, “sees” through the main mirror with a diameter of 2.4 meters. Its total surface area is only 4.5 m 2 .
Its replacement, the James Webb super telescope, will receive a composite mirror with a diameter of 6.4 m and a total collecting surface area of 25 m 2 . The new telescope will become more sensitive to infrared radiation from the most distant space systems – this is the merit of digital equipment, which has changed “cosmically” over the 30 years of Hubble’s life.
Deep space exploration is essential for scientific purposes. It contains millions of important data and clues to the past and future of the universe. But for the layman, these are just pretty pictures. It would be better to look from space to Earth, or to bring the Moon closer enough to see the traces of Neil Armstrong and Buzz Aldrin. Another space technology is responsible for this pleasure.The search for habitable planets and galaxies, of course, is encouraging, but simple earthly affairs have not been canceled. Therefore, astronauts have to shoot not only with the legendary Hubble, but also with equipment of a smaller caliber. Despite the fact that all the equipment in space is autonomous and controlled remotely, it can be assumed that it is the astronauts who “take pictures” with the help of telescopes and autonomous probes – after all, they are engaged in the maintenance, repair and adjustment of all equipment.
Michael Goode refurbishing the Hubble. year 2012.
Selfie of planet earth
Astronauts follow the daily business with the help of artificial satellites, probes and rovers. They are found in the Earth, Moon, Mars and other planets of the solar system. It is these space systems that make it possible to take beautiful photographs with high detail .
There are already more than 5,000 of them. These are artificial satellites, some of which have already been disabled, but several hundred still perform a variety of tasks – from transmitting cellular data and broadcasting television , to receiving and processing meteorological data. Some of them are equipped with cameras, with the help of which we observe the planet on a fantastic scale – like in Google Maps.
Quality photos come from a variety of sources. Google uses satellites Landsat 7 and Landsat 8, and in September 2021 a new Landsat 9 will appear. It will be equipped with advanced cameras with extended light coverage: the number of visible waves will exceed the capabilities of existing systems several times.
In 2021, mankind made another hyper-break in the study of the planets: the new Mars rover Perseverance safely reached the red planet and successfully landed (paraded) in one of the craters. Of course, this is not the first Martian of terrestrial origin: rovers have been traveling on the planet’s surface since 2003. Over the years, scientists have fixed errors and refined the technique.
Now technologies allow not only receiving several kilobytes, but even downloading sounds and huge panoramas from new rovers. The new Mars explorer is sending in gigabytes of information, including high-quality photographs, from which specialists create panoramas. For example, in one of the pictures, the robot captured a rock of an unusual shape, similar to an iduna (photo on the right):
Several artificial satellites ply around Mars, which monitor the atmosphere, take measurements and, of course, photograph the planet from a height of several thousand kilometers. This is exactly the genre of space photography that we are used to seeing on the Roscosmos website or in the NASA electronic gallery.
In the near future, this technique is going to arrange a photo session for the Perseverance rover – the satellite will show the landing site and track the movement of the rover from a height. It is possible that we are waiting for a new version of Google Maps – Google Mars with a detailed map of craters, plains, mountains and even a map of hurricanes.
The number of cameras in rovers is constantly growing. For example, Curiosity had 17 cameras that used 34mm and 100mm lenses. Seven cameras are mounted on the mast, one on the manipulator, and nine more on the rover itself. Only some of them were responsible for color photography and video filming, the rest acted as analyzers.
Perseverance already has 23 cameras, some of which were used to land on the planet. So, a wide-angle camera tracked the operation of the parachute and the landing module and was used to correct the maneuver. It produces images with a size of 1024 x 1024 pixels. Another camera is used when traveling on the surface and working with a manipulator. She “sees” at a distance of up to 15 meters. Photo size – 5120 x 3840 pixels, resolution – 20 megapixels. There are six cameras to prevent danger while driving and two color stereo navigation cameras that detect a golf ball at a distance of up to 25 meters. A camera with a macro lens looks into the top of the tube after sampling, taking microscopic pictures of the samples. A pair of cameras captures color photos, videos and 3D stereo images similar to what the human eye sees. Interesting,
Views of the moon
The automatic interplanetary station Lunar Reconnaissance Orbiter flies around the Moon. She knows how to take pictures with high detail:
Luna smiles at the camera. The merry crater congratulates the Earthlings. Photo taken on Halloween.
The LRO satellite system has been in operation since 2009. The main mission is a detailed study of the lunar surface, analysis of the atmosphere, the search for suitable landing sites for manned spacecraft and the search for unsuccessfully landed equipment.
Seven modules are responsible for the versatile capabilities of the satellite: CRaTER, DLRE, LAMP, LEND, LOLA, LROC and Mini-RF. The LROC optical camera module is used for photos with high detail and wide coverage. This is the chamber module of the station, the “eyes” of the satellite. The system has three supercams at its disposal: two narrow-angle NACs and one wide-angle WAC.
LROC NAC – two narrow-angle monochrome cameras with a very small field of view. They are designed for detailed surveys of the lunar surface. In civilian optics, this is more often called long-focus optics or telephoto lenses. For maximum approximation, lenses with a focal length of 700 mm are installed there – 82 times shorter than that of the Hubble. The satellite is located in close proximity to the surface to be filmed, therefore, even a modest lens by the standards of space is enough to see every stone on the surface.
One of the NAC cameras – most of the device is occupied by a hood to protect it from glare and flare from sunlight.
Cameras shoot detailed maps of lunar craters, seas and elevations in stereo. In other words, they are just two black and white cameras with powerful telephoto lenses:
The central peak of Tycho crater. Height – about 2400 meters
The research station often turns on wide-angle optics and takes panoramas with the LROC WAC camera. It is a sensor with a set of different filters and lenses that see in several light spectra: from visible wavelengths of 415-690 nm to ultraviolet wavelengths of 320 nm and 360 nm.
WAC camera. The wide-angle lens for the visible spectrum has a focal length of 6 mm. The lens for shooting in ultraviolet “sees” even wider – with a focal length of 4.7 mm.
The camera can operate in color and black-and-white modes, and shoots in a resolution of 60 to 600 megapixels – the resolution varies within 56 lines per 1 mm. That’s enough to make super-sharp panoramas in incredible colors:
Sometimes these photos are even more interesting than close-ups.
Using a wide-angle module together with the LOLA laser altimeter, the station made a real discovery: it “sees” craters, which, due to the peculiarities of the movement of the Sun and Moon, are never illuminated by sunlight.