Dilip Simeon's blog

NASA astronaut  Michael Collins , who stayed behind in the command module of Apollo 11 on July 20, 1969 while Neil Armstrong and Buzz Aldrin travelled to the lunar surface to become the first humans to walk on the moon, passed away on Wednesday April 28, at age 90, his family said.  Selected as part of NASA’s third group of 14 astronauts in 1963, Collins flew in space twice. His first spaceflight was on Gemini 10 in 1966, in which he and Command Pilot John Young performed orbital rendezvous with two spacecraft and undertook two extravehicular activities (EVAs, also known as spacewalks). On the 1969 Apollo 11 mission he became one of 24 people to fly to the Moon, which he orbited thirty times. He was the fourth person (and third American) to perform a spacewalk, the first person to have performed more than one spacewalk, and, after Young, who flew the command module on Apollo 10, the second person to orbit the Moon alone. Collins took the photo above of the Apollo 11 lunar modu...

This month marks 20 years of continuous human habitation of space on the ISS. The ISS is an orbiting laboratory for conducting scientific and technological experiments in microgravity. It is an extraterrestrial base for learning how to live and work in a remote, isolated and confined environment to prepare for exploring other planets. It is also a home to the astronauts and cosmonauts there. A new set of images by Italian astronaut Paolo Nespoli and photographer Roland Miller captures the station’s interiors through an artistic, minimalist eye.  View of ISS from departing Soyuz TMA-20 spacecraft, Low Earth Orbit, 2011 https://www.theguardian.com/artanddesign/gallery/2020/nov/10/gimme-some-space-inside-the-international-space-station-in-pictures

Harvard professor Avi Loeb says the potential for a great mind to revolutionize physics is greater than ever...  Obviously Einst ein was very visionary, but also in a sense, he had peers: people like Karl Schwarzchild and Edwin Hubble,  who were doing work that would help him test and correlate his theories. I've wondered, say, if Einstein were born 30 years later, would someone else have figured out relativity, and the photoelectric effect, and so on? ..  That's a good question. Physics is about nature, right? So we're trying to learn about nature. We're trying to understand nature and you know, so, in that sense, we collect data and eventually someone comes up with the right idea. The question is, how long does that take? What I'm saying is, I believe that the same ideas would have been developed. I don't know how close to the time that Einstein and thought about them, but eventually. . . . it would take maybe a few more deca...

The usual story of the Universe has a beginning, middle, and an end. It began with the Big Bang 13.8 billion years ago when the Universe was tiny, hot, and dense. In less than a billionth of a billionth of a second, that pinpoint of a universe expanded to more than a billion, billion times its original size through a process called “cosmological inflation”. Next came “the graceful exit”, when inflation stopped. The universe carried on expanding and cooling, but at a fraction of the initial rate. For the next 380,000 years, the Universe wa so dense that not even light could move through it – the cosmos was an opaque, superhot plasma of scattered particles. When things finally cooled enough for the first hydrogen atoms to form, the Universe swiftly became transparent. Radiation burst out in every direction, and the Universe was on its way to becoming the lumpy entity we see today, with vast swaths of empty space punctuated by clumps of particles, dust, stars, black holes, galaxies...

What determines our fate? To the Stoic Greek philosophers, fate is the external product of divine will, ‘the thread of your destiny’. To transcendentalists such as Henry David Thoreau, it is an inward matter of self-determination, of ‘what a man thinks of himself’. To modern cosmologists, fate is something else entirely: a sweeping, impersonal physical process that can be boiled down into a single, momentous number known as the Hubble Constant. The Hubble Constant can be defined simply as the rate at which the Universe is expanding, a measure of how quickly the space between galaxies is stretching apart. The slightest interpretation exposes a web of complexity encased within that seeming simplicity, however. Extrapolating the expansion process backward implies that all the galaxies we can observe originated together at some point in the past – emerging from a Big Bang – and that the Universe has a finite age. Extrapolating forward presents two starkly opposed futures, either an en...

The spectacle of Earth suspended in space was so overwhelming for Edgar Mitchell that the Apollo 14 astronaut and sixth man on the moon wanted to grab politicians by the scruff of the neck and drag them into space to witness the view. ‘An instant global consciousness’: the Earth viewed from the Apollo 17 mission in 1972. Astronauts have reported an intense feeling upon seeing Earth from space, known as the ‘Overview effect’. Photograph: Getty Image Such drastic measures may not be necessary, however. Scientists are about to welcome the first participants on an unprecedented clinical trial that aims to reproduce the intense emotional experience, known as the “Overview effect”, from the comfort of a health spa. If the trial goes well, what led Mitchell to develop “an instant global consciousness” and a profound connection to Earth and its people could be recreated with nothing more than a flotation tank, a half tonne of Epsom salts, and a waterproof virtual reality (VR) headset. ...

Fifty years ago this week, a former navy pilot created one of the most revolutionary artistic masterpieces of the 20th century, one we have yet to fully assimilate. His name was  Neil Armstrong  and his astonishing act of creativity is a photograph of his  Apollo 11 crewmate  Buzz Aldrin  standing on the Sea of Tranquillity on the moon. Not that you can see Aldrin’s face. His features and flesh are hidden inside a thickly padded white spacesuit, its visor reflecting the tiny figure of Armstrong himself, beside the gold-coloured legs of the lunar lander. NASA This effacement of Aldrin came about because Apollo astronauts wore visors lined with gold to protect their eyes from sunlight. Yet these reflective qualities are part of what makes this such a powerful, complex image, one in which we can see two lunar horizons. Behind Aldrin, the moon’s bright surface recedes to a blue horizon against the black void of space. Meanwhile, reflected and warped by the he...

The Sculptor GalaxyBernard Miller, Martin Pugh (USA). This is an image of NGC 253, also known as the Sculptor Galaxy. It is a spiral galaxy about 11 million light years away in the constellation Sculptor. It is a starburst galaxy, which means it undergoes periods of intense star formation and is the largest galaxy in a group of galaxies called the Sculptor Group.  Photograph: Bernard Miller and Martin Pugh/National Maritime Museum see more: https://www.theguardian.com/science/gallery/2019/jun/19/astronomy-photographer-of-the-year-2019-shortlist-in-pictures

It says something about our historical moment – or about the intrinsic limits of our capacity for wonder – that the image of this physical reality is so effortlessly normalised. We probably do less stargazing, as a species, than at any previous moment in human history, but the old reflex to anthropomorphise the universe, to insist on ourselves in the centre of it, persists...As TS Eliot observed in his meditation on Einstein’s space-time continuum in Burnt Norton, “humankind cannot bear too much reality”. The science proves the black hole is way beyond most of our understanding, but the evidence now in front of our eyes reminds us that the simplest principle of the universe remains the hardest for us to grasp: it’s not about us. A f ew years ago, during a period of insomnia, I briefly got into the habit of contributing to the online project  Galaxy Zoo . I would log on to a website that presented, one after another, singular images of tens of thousands of galaxies observed by...

Astronomers have taken the first ever image of a black hole, which is located in a distant galaxy. It measures 40 billion km across - three million times the size of the Earth - and has been described by scientists as "a monster". The black hole is 500 million trillion km away and was photographed by a network of eight telescopes across the world. Details have been published today in Astrophysical Journal Letters. It was captured by the Event Horizon Telescope (EHT), a network of eight linked telescopes. Prof Heino Falcke, of Radboud University in the Netherlands, who proposed the experiment, told BBC News that the black hole was found in a galaxy called M87. "What we see is larger than the size of our entire Solar System," he said. "It has a mass 6.5 billion times that of the Sun. And it is one of the heaviest black holes that we think exists. It is an absolute monster, the heavyweight champion of black holes in the Universe." The image sho...

On December 18, 2018, around noon local time, a huge fireball was reported at a remote spot over the Kamchatka peninsula, in the Russian far east. Since the location is very remote, there were no visual reports of the explosion and after, but monitoring stations set up worldwide to detect nuclear explosions recorded the low-frequency sound waves caused by this cataclysmic event. The event was also captured by cameras on a Japanese weather satellite. The explosion was caused by the burning of a meteor 10 metres in diameter, weighing more than 1,400 tonnes and moving at more than 100,000 kph which burnt itself at a height of around 25 km in the atmosphere. The energy released by the event is estimated to be equivalent to around 170 kilotons of TNT. To get a perspective on this number, the total energy released in the atomic bombing of Hiroshima was about 10 times smaller. Pale blue dot - Earth captured in rare photograph from Saturn spacecraft Cassini Chicxulub asteroid impact: Stu...

More than four hundred years ago, around 13.8 billion years after the beginning of the universe, in September 1608, a Dutchman from Zeeland came to The Hague announcing he’d invented an instrument “by means of which all things at a very great distance can be seen as if they were nearby.”  The prospect was thrilling. European explorers had spent centuries crossing wide oceans in hopes of finding distant lands to claim for their countries, and they were doing so with increased fervor - bringing the resources of faraway places closer to home by establishing trade routes; collapsing cultural distance by eradicating languages, religious practices, ceremonies, myths, and stories; forcing distant others to charade as Europeans with imposed cosmologies and worldviews - since  Christopher Columbus  had pulled a new world closer, 116 years before the seeing instrument was introduced. The soldiers who were convened at The Hague that day seized on it as a way to spot enemie...

Two tiny robots have landed safely on an  asteroid  after a Japanese spacecraft  dropped them there on Friday . The scientists behind the historic mission expressed their delight as the rovers sent back the first images from the surface of the space rock Ryugu. Dubbed MINERVA-II1, the robotic explorers are the first of their kind to be successfully landed on an asteroid. The Japanese space agency JAXA announced that both units were operational after a period of silence between the unmanned spacecraft Hayabusa-2 depositing them and connection being established with the team on Earth. “I cannot find words to express how happy I am that we were able to realise mobile exploration on the surface of an asteroid,” said Hayabusa-2 project manager Dr Yuichi Tsuda. The rovers will use the low gravity conditions on Ryugu to hop across the asteroid’s surface, measuring temperatures and sending images back to Earth via Hayabusa-2... read more: https://www.independe...

Astronomers have found compelling evidence that there is a huge reservoir of liquid water buried a mile under the ice near the south pole on  Mars .  Radar measurements taken from the European  Space  Agency’s Mars Express orbiter spotted the 12 mile-wide stretch of water at the base of a thick slab of polar ice in a region known as Planum Australe. It is the first time that researchers have identified a stable body of liquid water on the red planet. The finding raises the likelihood that any microbial life that arose on Mars may continue to eke out a rather bleak existence deep beneath the surface.   “We discovered water on Mars,” said Roberto Orosei at the National Institute of Astrophysics in Bologna. Any other explanation for the bright reflections the scientists saw in their radar observations was “untenable”, he added. Details of the finding are reported in the journal,  Science . Today, the most obvious signs that Mars was once a wet...

Scientists have been mystified by cosmic rays since they were found more than a century ago, pouring down onto Earth. Despite their huge number and intense power, it has been unclear where they come from. The new discovery could finally explain where cosmic rays originate. If correct, the answer would be a fittingly spectacular phenomenon deep in the universe.  The neutrinos appear to be spewing out of fast spinning supermassive black holes and the discovery could give us an entirely new way of looking at the universe. The particles might be a “third messenger” carrying energy from elsewhere in the cosmos, in addition to light and gravitational waves. If so, the newly observed particle would be an unprecedented new way of understanding some of the most intense and mysterious phenomena in the universe. Neutrinos could be doubly helpful because they have no mass and travel in an almost entirely straight line through the universe – which makes them very d...

Einstein has been proven right in spectacular style. Scientists have conducted a precise test of the way gravity works outside our solar system. It marks the first time that Einstein's general theory of relativity has been tested at such a large scale. The general theory of relativity, also known as GR, was first proposed in 1915. But its implications are huge, and therefore have never been tested fully. Despite that, scientists rely on it to explain the strange behaviour of our universe. The new study shows that they haven't been wrong to do so. For instance, scientists have known since 1929 that the universe is expanding, but in 1998 found that the expansion had sped up and was going more quickly than it did in the past. That can only make sense if the universe is filled with a mysterious substance called dark energy – but that in turn relies on GR being correct at the scale of galaxies. As such, our very understanding of the universe relies on GR being correct. ...

Nasa’s Curiosity rover has found organic matter preserved on Mars, in a discovery that could suggest it was once home to life.  The molecules represent an intriguing suggestion that Mars has been far more alive than we ever knew. While the discovery does not shed light on whether Mars was once home to alien life, and whether it could still be, the findings could be the result of ancient life there.  “The chances of being able to find signs of ancient life with future missions, if life ever was present, just went up,” said Curiosity’s project scientist, Ashwin Vasavada of Nasa’s Jet Propulsion Laboratory in Pasadena, California.  Experts say that the findings should propel us to look for conclusive evidence of alien life living on the planet.  “With these new findings, Mars is telling us to stay the course and keep searching for evidence of life,” said Thomas Zurbuchen, associate administrator for the Science Mission Directorate at Nasa h...

I have in my hand a little book titled  The Starry Messenger  ( Sidereus Nuncius  in its original Latin), written by the Italian mathematician and scientist Galileo Galilei in 1610. There were 550 books in the first printing of  Messenger . One hundred and fifty still remain. A few years ago, Christie’s valued each first edition at between $600,000 and $800,000. My paperback copy was printed in 1989 for about $12. Although the history of science has not awarded  Messenger  the same laurels as Newton’s  Principia or Darwin’s  On the Origin of Species , I regard it as one of the most consequential volumes of science ever published. In this little book, Galileo reports what he saw after turning his new telescope toward the heavens: strong evidence that the heavenly bodies are made of ordinary material, like the winter ice at Lute Island. The result caused a revolution in thinking about the separation between heaven and earth, a mind-bending expa...

There’s been no shortage of shows this century seeking to dissect and expound on the strange natural mysteries of Earth.  David Attenborough  managed to  jumpstart things  with the BBC’s  Blue Planet  back in the day, and then with  Planet Earth . Now, every season seems to herald a new mini-series focused on showing exactly how wondrous and unique our third rock from the sun really is. One Strange Rock , National Geographic Channel’s ten-episode series produced by  Darren Aronofsky  and  Will Smith  (who also doubles as a narrator) is just the latest in this entry, but with a twist: Each episode is hosted by an astronaut who has been to space, using the stories of what they’ve seen and heard and felt while drifting weightlessly in Earth’s orbit to regale Earthlings about the unique home we have, unlike anything we’re likely to discover out in the rest of the universe. “It might be the weirdest place in the universe,” Smith s...

NASA celebrates Hubble's birthday each year by giving us a gift - a new, breath-taking view of our universe. The latest birthday card: this elegant swirl of galaxies dancing in tandem deep in space. Last year - this bubble of stellar gases floating among the stars, like a diaphanous, cosmic jellyfish. Hubble has shown us radiant rose-shaped galaxies stretching across deep space; and dramatic towering clouds of gas teeming with the stuff of creation. Stars are born here. Year after year, in the infinite black canvas overhead, Hubble paints an ever-expanding picture of our universe - an awe-inspiring light show for us to admire ... and for scientists to study.      AMBER STRAUGHN: I believe Hubble has been the single most transformative scientific instrument that we've ever built. "Most transformative," says NASA astrophysicist Amber Straughn, because Hubble keeps improving our understanding of the universe. She showed us what Hubble discovered after staring for...