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Space Explorations – James Webb telescope

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By LIONEL PALLIYAGURU

I have been a sky gazer for more than four decades, a habit which started in my school days. As an amateur astronomer, stargazing usually starts from the backyard, with or without any supporting instruments like binoculars or telescopes. Identifications of whatever celestial objects become the first task, with the help of elders who are relaxing in the backyard invariably after supper.

As one develops a keen interest in astronomy, reading and studying astronomy with advanced telescopes become a reality. I have passed many stages in life, and enjoy my retirement life devoting ample time to my hobbies of which astronomy becomes my favourite subject.

It is well known that the James Webb Space Telescope (JWST or WEBB) is in operation with full potential, and incredible photos sent by JWST of distant galaxies could be seen on the NASA website as well as on public media.In order to explore the universe, various projects have been launched by many countries, of which NASA and the European space agency have contributed, by placing complex telescopes operational in outer space.

It is well known that the JWST is the most advanced telescope in operation since July 2022. It is equipped with the most sophisticated instruments with state-of-the-art technologies, and surpasses the capabilities of the Hubble Space Telescope (HST or HUBBLE), which was launched in 1990.

JWST was launched in December 2021 on an Ariane 5 rocket and travelled 1.6 million kilometres in space, to reach its final orbit around the sun, which takes one year to complete one revolution. Whereas its predecessor, HST was launched using Space Shuttle Discovery and placed in a geocentric orbit around the Earth with, an altitude of 547 kilometres at an elevation angle of 28 degrees with the equator. HST takes about 95 minutes to go around the earth and completes 15 orbits per day.

HST is equipped with instruments to probe the composition of the atmosphere of our solar system and extrasolar planets, normally referred to as exoplanets. HUBBLE can capture ultraviolet, visible, and near-infrared wavelengths of light. Although near-infrared radiation is detectable by the human eye, mid and far-infrared regions are less susceptible to the human eye. As the Hubble Space Telescope operates above 547 kilometres above Earth, Hubble can capture visible and infrared spectra with minimum interference.

In order to obtain a high degree of accuracy, space observations should be carried out outside the earth’s atmosphere, where obstruction to visible light and infrared light is minimal. Mathematician Joseph Louis Lagrange has discovered five locations with respect to the sun and earth, where observatories could be parked for various astronomical activities. They are known as Lagrange points and are denoted as L1, L2, L3, L4 and L5. in honour of him.

In these special locations, gravitational and rotational forces cancel each other out, creating ample parking space for telescopes and observatories. Any small mass object placed at the Lagrange point, moves in sync with the Earth, although they are in two different orbits around the sun.

The L2 point is advantageous in many ways for astronomy. The JWST can communicate continuously with Earth while providing a clear view into deep space. Interference from Sun and Earth could be kept to a minimum, as Sun and Earth are behind the telescope. Sun, Earth and L2 points are on a straight line keeping L2 at 151.5 million kilometres away from the Sun and 1.5 million kilometres away from the Earth. To stay in this position minimum station-keeping manoeuvres have to be performed occasionally, which reduces the propellant requirement considerably. As a result, the lifetime of the JWST is increased proportionately.

It took about twenty years to develop the most powerful telescope, costing 10 billion US dollars, in collaboration with the National Aeronautics and Space Administration (NASA), the European Space Agency (ESA), and the Canadian Space Agency (CSA). In addition to the main collaborators, there were about 15 other countries involved and contributed in many ways to making this mission a reality. This astronomical telescope was named as James Webb Space Telescope in honour of James Edwin Webb, who served NASA as an administrator during many critical space missions.

JWST design exceeds all the capabilities of its predecessor, and is expected to uncover the mysteries of the universe, by observing events that have taken place at a distance of 13.6 billion light-years away from Earth. In astronomy, distance is measured in light years. Light-year is the distance that light travels in a year at a speed of 300,000 kilometres per second, which is equivalent to 9.46 trillion kilometres.

Telescopes can go back in time. Looking out in space is looking back in time. Light takes time to travel vast distances in space to reach us. The light from the moon, which is about 390,000 kilometres away from us, takes 1.3 seconds to reach us meaning that we see the moon 1.3 seconds ago. Similarly, light takes about eight minutes to travel from the Sun, which is about 150 million kilometres away from the Earth. Inferring from that, what we see is the Sun about eight minutes ago. When the distances are in the order of billions, light takes years to reach the earth.

JWST is equipped with a) Mid-Infrared Instrument (MIRI), b) Near-Infrared Camera (NIRCam), c) Near-Infrared Spectrograph (NIRSpec), d) Fine Guidance Sensor (FGS), e) Near-Infrared Imager and Slitless Spectrograph(NIRISS). These equipment facilitate measurements of Redshift and Spectroscopy of various objects in the universe such as stars, galaxies, etc. As these instruments monitor the infrared region of the electromagnetic spectrum, all equipment has to be cryogenically cooled to avoid interference within equipment and from outside. The operating temperature is set to minus 266 degrees celsius, which is closer to absolute zero. Absolute zero is minus 273.15 degrees celsius, and the lowest possible temperature to reach. Extremely low operating temperature indicates the unprecedented sensitivity of its infrared equipment.

NASA claims that the sensitivity of infrared equipment onboard the WEBB could detect the heat of a bumblebee at a distance from the moon. Further, details of a small coin of one-centimetre size could be seen at a distance of 40 kilometres away.

In astronomy, redshift has been classified into three categories namely; a) Gravitational, b)Doppler, and c) Cosmological. Redshift is a phenomenon applicable to light sources moving away from an observer. In general, redshift is defined as an apparent increase in the wavelength (or decrease in frequency) of light waves, received from a moving source away from an observer. This is due to the stretching of the wavelength towards the red boundary of the spectrum.

Conversely, when the moving source of light is approaching the observer, a decrease in the wavelength (or increase in frequency) occurs. This is due to apparent compression of wavelength towards the blue boundary of the spectrum known as Blueshift.

Also, when a star rotates, one edge of the star is moving towards us relative to its centre, while the other edge is moving away. As a result, light from one edge of a star is slightly red-shifted, while light from the other edge is slightly blue-shifted. Astronomers can use these two shifts in order to calculate how fast a star is rotating. The same approach can be used to calculate how fast a galaxy is rotating. By evaluating the Redshift, the distance and velocity of any space object could be calculated. Conversely, Blueshift provides parameters of distance and velocity of an approaching object.

Astronomical spectroscopy is mainly concerned with the analysis of objects such as stars, planets, nebulas, and galaxies in space. It is done by splitting the received infrared spectrum into its various wavelength components. The spectrum patterns of a star can be compared with known spectrum patterns of hydrogen, oxygen, carbon and other elements to determine the physical and chemical composition of the star.

The media has shown magnificent and colourful photos of various stars, galaxies and nebulas released by NASA. Anybody would wonder about the process of producing such stunning photos from faraway galaxies many light years away from the Earth. These images are captured using infrared cameras and the spectrum is split into many different frequency bands using filters. Different colours are assigned to each frequency band during processing to obtain spectacular photos. A similar process is being used in digital colour cameras in processing visible light photos.

James Webb Space Telescope is expected to function at full capacity for a minimum of 10 year period. Scientists and Astronomers work tirelessly to explore discoveries of our universe, and life beyond our Earth, which is one of the key objectives of this mission.

This writer could be contacted on – lionelpg@gmail.com



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Acid test emerges for US-EU ties

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European Commission President Ursula von der Leyen

European Commission President Ursula von der Leyen addressing the World Economic Forum in Davos, Switzerland on Tuesday put forward the EU’s viewpoint on current questions in international politics with a clarity, coherence and eloquence that was noteworthy. Essentially, she aimed to leave no one in doubt that a ‘new form of European independence’ had emerged and that European solidarity was at a peak.

These comments emerge against the backdrop of speculation in some international quarters that the Post-World War Two global political and economic order is unraveling. For example, if there was a general tacit presumption that US- Western European ties in particular were more or less rock-solid, that proposition apparently could no longer be taken for granted.

For instance, while US President Donald Trump is on record that he would bring Greenland under US administrative control even by using force against any opposition, if necessary, the EU Commission President was forthright that the EU stood for Greenland’s continued sovereignty and independence.

In fact at the time of writing, small military contingents from France, Germany, Sweden, Norway and the Netherlands are reportedly already in Greenland’s capital of Nook for what are described as limited reconnaissance operations. Such moves acquire added importance in view of a further comment by von der Leyen to the effect that the EU would be acting ‘in full solidarity with Greenland and Denmark’; the latter being the current governing entity of Greenland.

It is also of note that the EU Commission President went on to say that the ‘EU has an unwavering commitment to UK’s independence.’ The immediate backdrop to this observation was a UK decision to hand over administrative control over the strategically important Indian Ocean island of Diego Garcia to Mauritius in the face of opposition by the Trump administration. That is, European unity in the face of present controversial moves by the US with regard to Greenland and other matters of contention is an unshakable ‘given’.

It is probably the fact that some prominent EU members, who also hold membership of NATO, are firmly behind the EU in its current stand-offs with the US that is prompting the view that the Post-World War Two order is beginning to unravel. This is, however, a matter for the future. It will be in the interests of the contending quarters concerned and probably the world to ensure that the present tensions do not degenerate into an armed confrontation which would have implications for world peace.

However, it is quite some time since the Post-World War Two order began to face challenges. Observers need to take their minds back to the Balkan crisis and the subsequent US invasions of Afghanistan and Iraq in the immediate Post-Cold War years, for example, to trace the basic historic contours of how the challenges emerged. In the above developments the seeds of global ‘disorder’ were sown.

Such ‘disorder’ was further aggravated by the Russian invasion of Ukraine four years ago. Now it may seem that the world is reaping the proverbial whirlwind. It is relevant to also note that the EU Commission President was on record as pledging to extend material and financial support to Ukraine in its travails.

Currently, the international law and order situation is such that sections of the world cannot be faulted for seeing the Post World War Two international order as relentlessly unraveling, as it were. It will be in the interests of all concerned for negotiated solutions to be found to these global tangles. In fact von der Leyen has committed the EU to finding diplomatic solutions to the issues at hand, including the US-inspired tariff-related squabbles.

Given the apparent helplessness of the UN system, a pre-World War Two situation seems to be unfolding, with those states wielding the most armed might trying to mould international power relations in their favour. In the lead-up to the Second World War, the Hitlerian regime in Germany invaded unopposed one Eastern European country after another as the League of Nations stood idly by. World War Two was the result of the Allied Powers finally jerking themselves out of their complacency and taking on Germany and its allies in a full-blown world war.

However, unlike in the late thirties of the last century, the seeming number one aggressor, which is the US this time around, is not going unchallenged. The EU which has within its fold the foremost of Western democracies has done well to indicate to the US that its power games in Europe are not going unmonitored and unchecked. If the US’ designs to take control of Greenland and Denmark, for instance, are not defeated the world could very well be having on its hands, sooner rather than later, a pre-World War Two type situation.

Ironically, it is the ‘World’s Mightiest Democracy’ which is today allowing itself to be seen as the prime aggressor in the present round of global tensions. In the current confrontations, democratic opinion the world over is obliged to back the EU, since it has emerged as the principal opponent of the US, which is allowing itself to be seen as a fascist power.

Hopefully sane counsel would prevail among the chief antagonists in the present standoff growing, once again, out of uncontainable territorial ambitions. The EU is obliged to lead from the front in resolving the current crisis by diplomatic means since a region-wide armed conflict, for instance, could lead to unbearable ill-consequences for the world.

It does not follow that the UN has no role to play currently. Given the existing power realities within the UN Security Council, the UN cannot be faulted for coming to be seen as helpless in the face of the present tensions. However, it will need to continue with and build on its worldwide development activities since the global South in particular needs them very badly.

The UN needs to strive in the latter directions more than ever before since multi-billionaires are now in the seats of power in the principle state of the global North, the US. As the charity Oxfam has pointed out, such financially all-powerful persons and allied institutions are multiplying virtually incalculably. It follows from these realities that the poor of the world would suffer continuous neglect. The UN would need to redouble its efforts to help these needy sections before widespread poverty leads to hemispheric discontent.

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Features

Brighten up your skin …

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Hi! This week I’ve come up with tips to brighten up your skin.

* Turmeric and Yoghurt Face Pack:

You will need 01 teaspoon of turmeric powder and 02 tablespoons of fresh yoghurt.

Mix the turmeric and yoghurt into a smooth paste and apply evenly on clean skin. Leave it for 15–20 minutes and then rinse with lukewarm water

Benefits:

Reduces pigmentation, brightens dull skin and fights acne-causing bacteria.

* Lemon and Honey Glow Pack:

Mix 01teaspoon lemon juice and 01 tablespoon honey and apply it gently to the face. Leave for 10–15 minutes and then wash off with cool water.

Benefits:

Lightens dark spots, improves skin tone and deeply moisturises. By the way, use only 01–02 times a week and avoid sun exposure after use.

* Aloe Vera Gel Treatment:

All you need is fresh aloe vera gel which you can extract from an aloe leaf. Apply a thin layer, before bedtime, leave it overnight, and then wash face in the morning.

Benefits:

Repairs damaged skin, lightens pigmentation and adds natural glow.

* Rice Flour and Milk Scrub:

You will need 01 tablespoon rice flour and 02 tablespoons fresh milk.

Mix the rice flour and milk into a thick paste and then massage gently in circular motions. Leave for 10 minutes and then rinse with water.

Benefits:

Removes dead skin cells, improves complexion, and smoothens skin.

* Tomato Pulp Mask:

Apply the tomato pulp directly, leave for 15 minutes, and then rinse with cool water

Benefits:

Controls excess oil, reduces tan, and brightens skin naturally.

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Features

Shooting for the stars …

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That’s precisely what 25-year-old Hansana Balasuriya has in mind – shooting for the stars – when she was selected to represent Sri Lanka on the international stage at Miss Intercontinental 2025, in Sahl Hasheesh, Egypt.

The grand finale is next Thursday, 29th January, and Hansana is all geared up to make her presence felt in a big way.

Her journey is a testament to her fearless spirit and multifaceted talents … yes, her life is a whirlwind of passion, purpose, and pageantry.

Raised in a family of water babies (Director of The Deep End and Glory Swim Shop), Hansana’s love affair with swimming began in childhood and then she branched out to master the “art of 8 limbs” as a Muay Thai fighter, nailed Karate and Kickboxing (3-time black belt holder), and even threw herself into athletics (literally!), especially throwing events, and netball, as well.

A proud Bishop’s College alumna, Hansana’s leadership skills also shone bright as Senior Choir Leader.

She earned a BA (Hons) in Business Administration from Esoft Metropolitan University, and then the world became her playground.

Before long, modelling and pageantry also came into her scene.

She says she took to part-time modelling, as a hobby, and that led to pageants, grabbing 2nd Runner-up titles at Miss Nature Queen and Miss World Sri Lanka 2025.

When she’s not ruling the stage, or pool, Hansana’s belting tunes with Soul Sounds, Sri Lanka’s largest female ensemble.

What’s more, her artistry extends to drawing, and she loves hitting the open road for long drives, she says.

This water warrior is also on a mission – as Founder of Wave of Safety,

Hansana happens to be the youngest Executive Committee Member of the Sri Lanka Aquatic Sports Union (SLASU) and, as founder of Wave of Safety, she’s spreading water safety awareness and saving lives.

Today is Hansana’s ninth day in Egypt and the itinerary for today, says National Director for Sri Lanka, Brian Kerkoven, is ‘Jeep Safari and Sunset at the Desert.’

And … the all-important day at Miss Intercontinental 2025 is next Thursday, 29th January.

Well, good luck to Hansana.

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