Tag Archives: #photos

The Niels Bohr Institute Develops Calibration Target, Now On its Way to Mars (Planetary Science)

Researchers at the Niels Bohr Institute, University of Copenhagen, have developed a color reference for one of the cameras on NASA’s newest Mars mission, the robotic vehicle Perseverance. The vehicle, aka rover, has several cameras installed, but the atmospheric conditions on Mars change the colors recorded, depending on the amount of dust in the atmosphere and the time of acquisition of the photos. For these reasons the cameras need a reference in order to compare or calibrate its images accordingly. This reference has been developed and manufactured in a collaboration between the researchers, the workshop at the Niels Bohr Institute and local businesses, and supported by the Carlsberg Foundation.

The calibration target with color references and pictograms. The total height of the primary target is 45.5 mm (The vertical center, casting a shadow) while the base of the target fits inside a square with a side of 98 mm. Photo: NASA

The colors change on Mars and so does the possibility to compare recordings

“The calibration target consist of a small base, containing different, well-known ceramic color references”, Kjartan Kinch, Associate professor at the Niels Bohr Institute explains. “Obviously, we take a lot of pictures on Mars, and the camera on the rover can do a little more than your ordinary camera. It has different, so-called narrow-band color filters and can do more color analysis than yellow-red-green-blue. It can “see” UV light and move out into the infrared area as well. When you take a picture, it is the color of the photographed object times the color of the light which determines how we can “read” the photo. What happens is, quite simply, that the camera on the rover records a photo of e.g. rock formations and then, within half an hour or so, the camera turns to record a picture of the calibration target. When we have divided out the color of the light at the recording time, the picture is far more suited for comparison with earlier recordings or recordings from other areas. That is, in short, what our calibration target does”.

What is the purpose of the pictures of rocks and landscapes on Mars?

The rover has a robotic arm with a series of different instruments to investigate elements of the Martian surface. When a rock formation has been investigated for which elements and minerals it contains or other details, the pictures recorded of it can be used for comparison. So if this information is available – like the presence of a certain mineral in a single stone – and it is compared with pictures taken in a much wider perspective out into the landscape on Mars, it is possible to identify other rocks with similar properties of color – but obviously only if the pictures are read and interpreted correctly. Alternatively the camera can be used for identifying stones and rocks with dissimilar properties from former investigations. “If we have the detailed information from a single rock or a single area, we can check its color properties and assume that if the same color properties are present in the landscape, we shall find the same mineralogy here – we can expand detailed knowledge out into the landscape,” says Kjartan Kinch. “Moreover, our photographic information connects to observations from satellites and other instruments, precisely because we take pictures out into the landscape”.

The instrument is a further development of former calibration targets from the Niels Bohr Institute

The researchers and students from the Mars group have taken part in former missions and have improved on the instrument. Along the way a magnetic system, removing the ever present Martian dust from the color references has been developed, keeping the references as clean as possible. The dust on Mars is magnetic, so what started as an experiment on former missions has now become a built in element. “The aluminum base was designed and cut at the workshop of the Niels Bohr Institute, the magnets and ceramics ordered from international companies, the base was silvered and gold plated in Farum, engraved in Ishøj and the whole thing assembled in the Niels Bohr Institute clean room”, Kjartan Kinch explains.

Pictograms on the calibration target

The motto and pictograms seen on the Niels Bohr Institute target are made in collaboration with the team in the USA. There is a tiny stick protruding from the center casting a shadow, just like a solar watch. Solar watches traditionally have a motto, so the instrument was given one as well: “Two worlds, one beginning”. The pictograms show the development of life on Earth from bacterial life over plants and dinosaurs to people launching rockets into space. “It will be one of the most photographed objects on Mars, so we believed a decoration was justified”, Kjartan Kinch says.

The Mars mission Perseverance is part of a bigger mission to send samples back to Earth

This mission is in many ways similar to the very successful mission the rover Curiosity is still undertaking. It landed on Mars in 2012. The new rover is basically built using the same template. What’s new about Perseverance is that it will be covering another area than Curiosity and pick up samples from stones and rocks, later to be picked up by a collaborate ESA-NASA mission and sent back to Earth. So a set of samples from Mars are collected, hopefully telling us a lot about Mars later on. “But first we have to understand the landscape”, says Kjartan Kinch. We have to understand which locations are best suited for collecting samples, to gain maximum benefit from the mission. It is in this context we, at the Niels Bohr Institute, have contributed with a small, but important piece in a larger, scientific puzzle”.

Provided by University of Copenhagen Neil Bohr Institute

Hubble Captures Spectacular Photos of Jupiter and Its Icy Moon Europa (Planetary Science)

Two new photos, taken with the NASA/ESA Hubble Space Telescope, show Jupiter with its turbulent atmosphere and giant storms. One of the images also features Europa, one of Jupiter’s Galilean moons.

This image of Jupiter was taken by the NASA/ESA Hubble Space Telescope on August 25, 2020, when the planet was 653 million km (406 million miles) from Earth. Image credit: NASA / ESA / A. Simon, NASA’s Goddard Space Flight Center / M.H. Wong, University of California, Berkeley / OPAL Team.

A bright, white, stretched-out storm moving at 560 km per hour (348 mph) appeared at Jupiter’s mid-northern latitudes on August 18, 2020.

While it’s common for storms to pop up in this region, often several at once, this particular disturbance appears to have more structure behind it than observed in previous storms. Trailing behind the plume are small, counterclockwise dark clumps also not witnessed in the past.

Hubble shows that the Great Red Spot, rolling counterclockwise in the planet’s southern hemisphere, is ploughing into the clouds ahead of it, forming a cascade of white and beige ribbons.

The huge storm system is currently an exceptionally rich red color, with its core and outermost band appearing deeper red.

It now measures about 15,800 km (9,818 miles) across, and is still shrinking, as noted in telescopic observations dating back to 1930, but its rate of shrinkage appears to have slowed.

A multiwavelength observation in ultraviolet/visible/near-infrared light of Jupiter obtained by Hubble on August 25, 2020 is giving astronomers an entirely new view of the giant planet. Hubble’s near-infrared imaging, combined with ultraviolet views, provides a unique panchromatic look that offers insights into the altitude and distribution of the planet’s haze and particles. This complements Hubble’s visible-light pictures that show the ever-changing cloud patterns. In this photo, the parts of Jupiter’s atmosphere that are at higher altitude, especially over the poles, look red as a result of atmospheric particles absorbing ultraviolet light. Conversely, the blue-hued areas represent the ultraviolet light being reflected off the planet. A new storm at upper left, which erupted on August 18, 2020, is grabbing the attention of scientists in this multiwavelength view. The ‘clumps’ trailing the white plume appear to be absorbing ultraviolet light, similar to the center of the Great Red Spot, and Red Spot Jr. directly below it. This provides the astronomers with more evidence that this storm may last longer on Jupiter than most storms. Image credit: NASA / ESA / A. Simon, NASA’s Goddard Space Flight Center / M.H. Wong, University of California, Berkeley / OPAL Team.

The astronomers are noticing that another feature has changed: Oval BA, nicknamed as Red Spot Jr., which appears just below the Great Red Spot in the new images.

For the past few years, Oval BA has been fading in color to its original shade of white after appearing red in 2006.

However, now the core of this storm appears to be darkening to a reddish hue. This could hint that Red Spot Jr. is on its way to reverting to a color more similar to that of its cousin.

The images also show that Jupiter is clearing out its higher-altitude white clouds, especially along the planet’s equator, which is enveloped in an orangish hydrocarbon smog.

In one of the two images, the icy moon Europa is visible to the left of Jupiter.

Hubble also captured a new multiwavelength observation in ultraviolet/visible/near-infrared light of Jupiter, which is giving astronomers an entirely new view of the giant planet.

The telescope’s near infrared imaging, combined with ultraviolet views, provides a unique panchromatic look that offers insights into the altitude and distribution of the planet’s haze and particles.

This complements Hubble’s visible-light picture that shows the ever-changing cloud patterns.

This article is based on press-releases provided by the National Aeronautics and Space Administration and the European Space Agency.

The Cheerleader Effect Says You Look More Attractive When You’re With A Group (Psychology)

When it comes to presenting yourself online – such as your profile pic for Facebook or even Tinder – which type of photo do you chose? The selfie you’ve taken after careful consideration of lighting, hair and maybe makeup? (No doubt, you look great!) Or the group photo with friends, possibly less styled, but that captures a moment among peers?

It might come as a surprise that it’s the group photo will make you look more attractive – it’s a phenomenon known as the “cheerleader effect”.

The cheerleader effect is real, but perhaps not for the reasons you think. The group shot with friends may indeed communicate you are sociable and friendly, but this is not what is making you more attractive.

The real explanation boils down to how human brains deal with information.

First popularised by the television series How I Met Your Mother, the character Barney Stinson uses the term cheerleader effect to describe a woman appearing attractive when in a group, but not as an individual.

His interpretation was typical of American sitcoms, but Barney’s comments are founded in research.

In 2003, scientific evidence of the cheerleader effect was published in a paper where across five studies, both males and females were rated more attractive when presented as part of a group photo compared to a solo photo. The authors, Drew Walker and Edward Vul, presented 130 participants with group photographs containing three female faces or three male faces. Each face was then cropped from the photograph and presented individually.

Participants rated the attractiveness of faces presented in a group and individually. Regardless of gender, attractiveness ratings were higher when people were presented in a group compared to presented individually.

However, this does not mean the bigger the group – the more attractive you are. The authors found that group size, whether 4, 9, or 16 individuals, had no effect on attractiveness ratings. Basically, a handful of friends is all you need to take advantage of this effect.

The robustness of the cheerleader effect is best explained by looking at how your brain works, and understanding perception.

Humans tend not to process every individual detail they perceive in their environment. Instead of devoting significant attention to all individual characteristics, our brain quickly summarises the information as a group. Evidence even suggests that our brains may be wired for such categorisation.

Grouping perceptual information has a distinct evolutionary advantage, enhancing survival by reducing perceptual load (the burden of interpreting a scene from visual information).

This perceptual effect is best demonstrated with the Ebbinghaus Illusion.

Fig: Ebbinghaus Illusion: the two blue circles are exactly the same size – however, the one on the right appears larger. from http://www.shutterstock.com

In this illusion, the inside circles are identical in size, yet the surrounding information (i.e., surrounding circles) alters our perception. Here, rather than focusing on the individual characteristics of the inside circles, our perception is altered by the group information. This is known as top-down processing, where the whole element is perceived before individual characteristics. This is in contrast to bottom-up processing, where there is progression from the individual characteristics to the whole.

The same characteristics of this illusion extend to the cheerleader effect. In this effect, rather than attend to individual characteristics, we focus on the group as a whole.

Such an effect can even be applied to explain social biases. Social categorisation is the process of mentally categorising individuals into groups based on characteristics such as age, sex, and ethnicity. This quick categorisation of social information promotes fast social interactions – but has some serious and broader consequences.

The evidence suggests that presenting yourself with a group will tend to average out any “unattractive” individual characteristics. So, how can you use this information to your advantage?

Well, you can apply this information when selecting a profile picture. Perhaps you’re seeing someone new, and suspect they could be doing a little Facebook research on you. Select a profile picture of you and a few friends for maximum attractiveness. Bonus – group pictures can also demonstrate that you’re social.

Maybe you’re heading out to the pub to meet the local singles? Don’t forget your “wing” men/women (ideally a group of 4!).

And if you’re online dating, how about including some pictures of you and a few friends in your profile? However, remember to label yourself in the photo to avoid users finding your group photo attractive but moving on because they can’t figure out who in the photo you are.


You Are Bad At Choosing Good Picture Of Yourself, But Strangers Aren’t (Psychology)

Whether it’s a social network like Facebook or a job-seeker site like LinkedIn, most of us are guilty of overthinking our profile picture selection from time to time. It makes sense: The idea that the first impression can make or break the chance for a friendship, romantic connection, or new job is understandably nerve-wracking. Knowing that you shouldn’t be making that decision yourself, then, could come as a relief. According to a 2017 study, a stranger should be picking the photo for you.

For the study, which was conducted by the University of South Wales, the University of Western Australia, and the University of Sydney, researchers selected 102 students and collected a dozen pictures from each of their Facebook accounts. The students then rated each of their own pictures from a scale of one to 10 in the following categories: attractiveness, trustworthiness, dominance, confidence, and competence, all based solely on the specific picture. Then, 160 strangers rated the same pictures in the same categories. The rankings did not match. The pictures that the students thought were the best ones of themselves actually ranked less favorably among strangers, and vice versa. The researchers were surprised. “This result is contrary to the prediction based on self-presentation literature,” they wrote, “that participants would select more flattering images of themselves than of other people.”

Interestingly, several dating sites have already figured this out. Famously data-friendly company OKCupid once had a service called My Best Face that let strangers anonymously rate users’ dating-profile pictures. In 2016, the dating app Tinder began using an algorithm to choose users’ profile pictures for them based on which ones got the most right-swipes.

Fig: The top rows of picture are those selected by the person in the picture; those in the bottom row were selected by strangers.

YOU SEE WHAT STRANGERS DON’T KNOW

We each have a lifetime of experience looking at pictures of ourselves, so why are we so bad at choosing the best ones? The researchers have some ideas. For one, they say, what we know about ourselves creates a bias when interpreting our own facial expressions. You know you’re trustworthy, for example, so you automatically see a trustworthy person in the photo.

It’s also a possible result of the better-than-average effect, or the way you tend to rate yourself more positively than other people — thinking you’re the hottest thing on legs is likely to bias your own picture selection. Even more fascinating is that you perceive yourself a certain way before you even look at the pictures, making it difficult to differentiate the quality of one over the other. To you, it’s 12 different photos of the same person. To strangers, 12 pictures tell 12 different stories.


References: (1) https://cognitiveresearchjournal.springeropen.com/articles/10.1186/s41235-017-0058-3 (2) https://www.sciencealert.com/you-should-probably-let-a-stranger-pick-your-next-profile-picture (3) http://download.springer.com/static/pdf/180/art%253A10.1186%252Fs41235-017-0058-3.pdf?originUrl=http%3A%2F%2Fcognitiveresearchjournal.springeropen.com%2Farticle%2F10.1186%2Fs41235-017-0058-3&token2=exp=1493999521~acl=%2Fstatic%2Fpdf%2F180%2Fart%25253A10.1186%25252Fs41235-017-0058-3.pdf*~hmac=5256065eef278c5a26470c4e64d8ec1fc26f70d193a0c79e572f6c8063a00ffc (4) https://theblog.okcupid.com/the-4-big-myths-of-profile-pictures-41bedf26e4d (5) http://jesse.la/okcupids-mybestface-would-be-awesome-if-it-worked/ (6) https://www.wired.co.uk/article/tinder-smart-photos (7)