President Trump’s recent bombing of Iran’s nuclear sites marks a major turning point in the maintenance of global security. With war again erupting in the Middle East, the United States […]
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What does quantum physics have to do with vibrant oil paintings and the ghostly grin of a disappearing cat? Quite a lot, as it turns out. In this month’s Physics World Stories podcast, host Andrew Glester takes a colourful look at how we visualize – and try to make sense of – the curious world of quantum mechanics.
Felicity shares her journey from academia to art, and how her experience of number-colour synaesthesia – where numbers are associated with colours in her mind – shapes her creative process as she explores the elusive nature of quantum reality.
Later, Physics World features editor Tushna Commissariat introduces the Physics WorldQuantum Briefing and delves into one of its stories, ‘The curious case of quantum Cheshire cats’. It explores the strange phenomenon where a particle’s properties seem to be in a different place from the particle itself – reminiscent of Lewis Carroll’s famous feline in Alice in Wonderland, whose grin lingers even after he’s gone.
You’ll find plenty more on the history, mystery and industry of quantum mechanics in the free-to-read Quantum Briefing. Stay tuned to the Physics World quantum channel for more IYQ content throughout the year. You can already enjoy a blog series from Matin Durrani, reporting from the tiny North Sea archipelago Helgoland, where Heisenberg made his breakthrough in quantum mechanics 100 years ago.
Proton energies achievable in laser accelerators could be tripled by using specially designed micronozzle targets, according to computer simulations done by physicists in Japan and India. In their design, the electric field generated in the micronozzle would be funnelled towards the outgoing protons, allowing the acceleration to proceed for much longer. The researchers believe that the research could be useful in nuclear fusion, hadron therapy and materials science.
Conventional accelerators use oscillating electric fields to drive charged particles to relativistic speeds. The Large Hadron Collider at CERN, for example, uses radio-frequency oscillations to achieve proton energies of nearly 7 TeV.
These accelerators tend to be very large, which limits where they can be built. Laser acceleration, which involves using high-energy laser pulses to accelerate charged particle, offers a way to create much more compact accelerators.
Crucial to inertial confinement
Laser acceleration is crucial to inertial confinement fusion, and high energy proton beams produced by laser accelerators are used in scientific laboratories for a variety of scientific applications including laboratory astrophysics.
The standard techniques for laser acceleration involve firing a laser pulse at a proton target surrounded by metal foil. Solid hydrogen only exists near absolute zero, so the proton target can be a hydrogen-rich compound such as a hydride or a polymer. The femtosecond laser pulse concentrates a huge amount of energy into a tiny area and this instantly turns the target into a plasma. The light’s oscillating electromagnetic field drives electrons through the plasma, leaving behind the much heavier ions and creating a huge electric field that can accelerate protons.
In the new work, physicist Masakatsu Murakami and colleagues at the University of Osaka in Japan, together with researchers at the Indian Institute of Technology Hyderabad, used computer modelling to examine the effect of changing the shape of the metal surrounding the target from a simple planar foil to a two-headed nozzle, with the target placed at the narrowest point. During the first stage of the acceleration process, the wide head of the nozzle behaves like a lens, concentrating the electric field from a wide area to produce an enhanced flow of hot electrons towards the centre. This electric current on the nozzle enhances ablation of protons from the hydrogen rod, kicking them forward into the vacuum.
“Just like a rocket nozzle”
Subsequently, the electrons keep moving through the “skirt” of the nozzle, creating a powerful electric field that, owing to the nozzle’s shape, remains focused on the accelerating proton pulse as it travels away into the vacuum. “With the single hydrogen rod and the single foil, the protons are accelerated only during the laser illumination,” explains Murakami. “However, interestingly with the micronozzle target, the acceleration keeps going even after the laser pulse illumination…Most of the plasma expands in a small volume together with the protons – just like a rocket nozzle,” he says. Whereas the standard proton energies achievable with a laser accelerator today are around 400 MeV, the researchers estimate that their micronozzle design could allow energies into the gigaelectronvolt regime without changing anything else.
Murakami has been studying nuclear fusion for 40 years and believes that “this method will be used for fast ignition of laser fusion”. However, he says, its potential uses go far beyond this. Proton beam therapy generally uses protons with energies of 200–300 MeV to treat cancer by delivering a high dose of radiation to the tumour and a much lower dose to surrounding healthy tissue. “Even higher energy is required to target cancers that are located in deeper parts of the body,” he says. The technique could also be useful for materials science techniques such as proton radiography or for simulation of the physics of astrophysical objects such as neutron stars. “I’m planning to do proof of principle experiments in the near future,” says Murakami.
Accelerator physicist Nicholas Dover of Imperial College London describes the work as “very interesting,” adding, “This target that they propose is a very complex thing to make. It would be a big project for a target fabrication lab to generate something like this – it’s not something we just cook up in our lab. Having these numerical optimizations is really helpful for us.” He notes, however, that one reason accelerator physicists often use planar targets (essentially pieces of kitchen foil) is the need to replace them in every shot. In scientific applications, this may not matter, he says. Applications in fields like medicine, however, would probably require the development of mass production facilities to fabricate the targets economically.
Eighty years ago, presidential science advisor Vannevar Bush delivered to President Harry S. Truman a remarkable report entitled “Science-The Endless Frontier.” In this report, Bush described the immense benefits of […]
Light has always played a central role in healthcare, enabling a wide range of tools and techniques for diagnosing and treating disease. Nick Stone from the University of Exeter is a pioneer in this field, working with technologies ranging from laser-based cancer therapies to innovative spectroscopy-based diagnostics. Stone was recently awarded the Institute of Physics’ Rosalind Franklin Medal and Prize for developing novel Raman spectroscopic tools for rapid in vivo cancer diagnosis and monitoring. Physics World’s Tami Freeman spoke with Stone about his latest research.
What is Raman spectroscopy and how does it work?
Think about how we see the sky. It is blue due to elastic (specifically Rayleigh) scattering – when an incident photon scatters off a particle without losing any energy. But in about one in a million events, photons interacting with molecules in the atmosphere will be inelastically scattered. This changes the energy of the photon as some of it is taken by the molecule to make it vibrate.
If you shine laser light on a molecule and cause it to vibrate, the photon that is scattered from that molecule will be shifted in energy by a specific amount relating to the molecule’s vibrational mode. Measuring the wavelength of this inelastically scattered light reveals which molecule it was scattered from. This is Raman spectroscopy.
Because most of the time we’re working at room or body temperatures, most of what we observe is Stokes Raman scattering, in which the laser photons lose energy to the molecules. But if a molecule is already vibrating in an excited state (at higher temperature), it can give up energy and shift the laser photon to a higher energy. This anti-Stokes spectrum is much weaker, but can be very useful – as I’ll come back to later.
How are you using Raman spectroscopy for cancer diagnosis?
A cell in the body is basically a nucleus: one set of molecules, surrounded by the cytoplasm: another set of molecules. These molecules change subtlety depending on the phenotype [set of observable characteristics] of the particular cell. If you have a genetic mutation, which is what drives cancer, the cell tends to change its relative expression of proteins, nucleic acids, glycogen and so on.
We can probe these molecules with light, and therefore determine their molecular composition. Cancer diagnostics involves identifying minute changes between the different compositions. Most of our work has been in tissues, but it can also be done in biofluids such as tears, blood plasma or sweat. You build up a molecular fingerprint of the tissue or cell of interest, and then you can compare those fingerprints to identify the disease.
We tend to perform measurements under a microscope and, because Raman scattering is a relatively weak effect, this requires good optical systems. We’re trying to use a single wavelength of light to probe molecules of interest and look for wavelengths that are shifted from that of the laser illumination. Technology improvements have provided holographic filters that remove the incident laser wavelength readily, and less complex systems that enable rapid measurements.
Raman spectroscopy can classify tissue samples removed in cancer surgery, for example. But can you use it to detect cancer without having to remove tissue from the patient?
Absolutely, we’ve developed probes that fit inside an endoscope for diagnosing oesophageal cancer.
Earlier in my career I worked on photodynamic therapy. We would look inside the oesophagus with an endoscope to find disease, then give the patient a phototoxic drug that would target the diseased cells. Shining light on the drug causes it to generate singlet oxygen that kills the cancer cells. But I realized that the light we were using could also be used for diagnosis.
Currently, to find this invisible disease, you have to take many, many biopsies. But our in vivo probes allow us to measure the molecular composition of the oesophageal lining using Raman spectroscopy, to be and determine where to take biopsies from. Oesophageal cancer has a really bad outcome once it’s diagnosed symptomatically, but if you can find the disease early you can deliver effective treatments. That’s what we’re trying to do.
Tiny but mighty (left) A Raman probe protruding from the instrument channel of an endoscope. (right) Oliver Old, consultant surgeon, passing the probe down an endoscope for a study led by the University of Exeter, with the University of Bristol and Gloucestershire Hospitals NHS Foundation Trust as partners. (Courtesy: RaPIDE Team)
The very weak Raman signal, however, causes problems. With a microscope, we can use advanced filters to remove the incident laser wavelength. But sending light down an optical fibre generates unwanted signal, and we also need to remove elastically scattered light from the oesophagus. So we had to put a filter on the end of this tiny 2 mm fibre probe. In addition, we don’t want to collect photons that have travelled a long way through the body, so we needed a confocal system. We built a really complex probe, working in collaboration with John Day at the University of Bristol – it took a long time to optimize the optics and the engineering.
Are there options for diagnosing cancer in places that can’t be accessed via an endoscope?
Yes, we have also developed a smart needle probe that’s currently in trials. We are using this to detect lymphomas – the primary cancer in lymph nodes – in the head and neck, under the armpit and in the groin.
If somebody comes forward with lumps in these areas, they usually have a swollen lymph node, which shows that something is wrong. Most often it’s following an infection and the node hasn’t gone back down in size.
This situation usually requires surgical removal of the node to decide whether cancer is present or not. Instead, we can just insert our needle probe and send light in. By examining the scattered light and measuring its fingerprint we can identify if it’s lymphoma. Indeed, we can actually see what type of cancer it is and where it has come from.
Novel needle Nick Stone demonstrates a prototype Raman needle probe. (Courtesy: Matthew Jones Photography)
Currently, the prototype probe is quite bulky because we are trying to make it low in cost. It has to have a disposable tip, so we can use a new needle each time, and the filters and optics are all in the handpiece.
Are you working on any other projects at the moment?
As people don’t particularly want a needle stuck in them, we are now trying to understand where the photons travel if you just illuminate the body. Red and near-infrared light travel a long way through the body, so we can use near-infrared light to probe photons that have travelled many, many centimetres.
We are doing a study looking at calcifications in a very early breast cancer called ductal carcinoma in situ (DCIS) – it’s a Cancer Research UK Grand Challenge called DCIS PRECISION, and we are just moving on to the in vivo phase.
Calcifications aren’t necessarily a sign of breast cancer – they are mostly benign; but in patients with DCIS, the composition of the calcifications can show how their condition will progress. Mammographic screening is incredibly good at picking up breast cancer, but it’s also incredibly good at detecting calcifications that are not necessarily breast cancer yet. The problem is how to treat these patients, so our aim is to determine whether the calcifications are completely fine or if they require biopsy.
We are using Raman spectroscopy to understand the composition of these calcifications, which are different in patients who are likely to progress onto invasive disease. We can do this in biopsies under a microscope and are now trying to see whether it works using transillumination, where we send near-infrared light through the breast. We could use this to significantly reduce the number of biopsies, or monitor individuals with DCIS over many years.
Light can also be harnessed to treat disease, for example using photodynamic therapy as you mentioned earlier. Another approach is nanoparticle-based photothermal therapy, how does this work?
This is an area I’m really excited about. Nanoscale gold can enhance Raman signals by many orders of magnitude – it’s called surface-enhanced Raman spectroscopy. We can also “label” these nanoparticles by adding functional molecules to their surfaces. We’ve used unlabelled gold nanoparticles to enhance signals from the body and labelled gold to find things.
During that process, we also realized that we can use gold to provide heat. If you shine light on gold at its resonant frequency, it will heat the gold up and can cause cell death. You could easily blow holes in people with a big enough laser and lots of nanoparticles – but we want to do is more subtle. We’re decorating the tiny gold nanoparticles with a label that will tell us their temperature.
By measuring the ratio between Stokes and anti-Stokes scattering signals (which are enhanced by the gold nanoparticles), we can measure the temperature of the gold when it is in the tumour. Then, using light, we can keep the temperature at a suitable level for treatment to optimize the outcome for the patient.
Ideally, we want to use 100 nm gold particles, but that is not something you can simply excrete through the kidneys. So we’ve spent the last five years trying to create nanoconstructs made from 5 nm gold particles that replicate the properties of 100 nm gold, but can be excreted. We haven’t demonstrated this excretion yet, but that’s the process we’re looking at.
This research is part of a project to combine diagnosis and heat treatment into one nanoparticle system – if the Raman spectra indicate cancer, you could then apply light to the nanoparticle to heat and destroy the tumour cells. Can you tell us more about this?
We’ve just completed a five-year programme called Raman Nanotheranostics. The aim is to label our nanoparticles with appropriate antibodies that will help the nanoparticles target different cancer types. This could provide signals that tell us what is or is not present and help decide how to treat the patient.
We have demonstrated the ability to perform treatments in preclinical models, control the temperature and direct the nanoparticles. We haven’t yet achieved a multiplexed approach with all the labels and antibodies that we want. But this is a key step forward and something we’re going to pursue further.
We are also trying to put labels on the gold that will enable us to measure and monitor treatment outcomes. We can use molecules that change in response to pH, or the reactive oxygen species that are present, or other factors. If you want personalized medicine, you need ways to see how the patient reacts to the treatment, how their immune system responds. There’s a whole range of things that will enable us to go beyond just diagnosis and therapy, to actually monitor the treatment and potentially apply a boost if the gold is still there.
Looking to the future, what do you see as the most promising applications of light within healthcare?
Light has always been used for diagnosis: “you look yellow, you’ve got something wrong with your liver”; “you’ve got blue-tinged lips, you must have oxygen depletion”. But it’s getting more and more advanced. I think what’s most encouraging is our ability to measure molecular changes that potentially reveal future outcomes of patients, and individualization of the patient pathway.
But the real breakthrough is what’s on our wrists. We are all walking around with devices that shine light in us – to measure heartbeat, blood oxygenation and so on. There are already Raman spectrometers that sort of size. They’re not good enough for biological measurements yet, but it doesn’t take much of a technology step forward.
I could one day have a chip implanted in my wrist that could do all the things the gold nanoconstructs might do, and my watch could read it out. And this is just Raman – there are a whole host of approaches, such as photoacoustic imaging or optical coherence tomography. Combining different techniques together could provide greater understanding in a much less invasive way than many traditional medical methods. Light will always play a really important role in healthcare.
This article is based on a session at the Institute of Physics’ Celebration of Physics in April 2025.
Dynamic PET imaging is an important preclinical research tool used to visualize real-time functional information in a living animal. Currently, however, the temporal resolution of small-animal PET scanners is on the order of seconds, which is too slow to image blood flow in the heart or track the brain’s neuronal activity. To remedy this, the Imaging Physics Group at the National Institutes for Quantum Science and Technology (QST) in Japan has developed an ultrasensitive small-animal PET scanner that enables sub-second dynamic imaging of a rat.
The limited temporal resolution of conventional preclinical PET scanners stems from their low sensitivity (around 10%), caused by relatively thin detection crystals (10 mm) and a short axial field-of-view (FOV). Thus the QST team built a system based on four-layer, depth-encoding detectors with a total thickness of 30 mm. The scanner has a 325.6 mm-long axial FOV, providing total-body coverage without any bed movement, while a small inner diameter of 155 mm further increases detection efficiency.
“The main application of the total-body small-animal PET (TBS-PET) scanner will be assessment of new radiopharmaceuticals, especially for cardiovascular and neurodegenerative diseases, by providing total-body rodent PET images with sub-second temporal resolution,” first author Han Gyu Kang tells Physics World. “In addition, the scanner will be used for in-beam PET imaging, and single-cell tracking, where ultrahigh sensitivity is required.”
Performance evaluation
The TBS-PET scanner contains six detector rings, each incorporating 10 depth-of-interaction (DOI) detectors. Each DOI detector comprises a four-layer zirconium-doped gadolinium oxyorthosilicate (GSOZ) crystal array (16×16 crystals per layer) and an array of multi-anode photomultiplier tubes. The team selected GSOZ crystals because they have no intrinsic radiation signal, thus enabling low activity PET imaging.
The researchers performed a series of tests to characterize the scanner performance. Measurements of a 68Ge line source at the centre of the FOV showed that the TBS-PET had an energy resolution of 18.4% and a coincidence timing resolution of 7.9 ns.
Imaging a NEMA 22Na point source revealed a peak sensitivity of 45.0% in the 250–750 keV energy window – more than four times that of commercial or laboratory small-animal PET scanners. The system exhibited a uniform spatial resolution of around 2.6 mm across the FOV, thanks to the four-layer DOI information, which effectively reduced the parallax error.
In vivo imaging
Kang and colleagues next obtained in vivo total-body PET images of healthy rats using a single bed position. Static imaging using Na18F and 18F-FDG tracers clearly visualized bone structures and glucose metabolism, respectively, of the entire rat body.
Moving to dynamic imaging, the researchers injected an 18F-FDG bolus into the tail vein of an anesthetized rat for 15 s, followed by a saline injection 15 s after injection. They acquired early-phase dynamic PET data every second until 27 s after injection. To enable sub-second PET imaging, they used custom-written software to subdivide the list-mode data (1 s time frame) into time frames of 0.5 s, 0.25 s and 0.1 s.
Dynamic PET images with a 0.5 s time frame clearly visualized the blood stream from the tail to the heart through the iliac vein and inferior vena cava for the first 2 s, after which the tracer reached the right atrium and right ventricle. At 4.0 s after injection, blood flowed from the left ventricle into the brain via the carotid arteries. The cortex and kidneys were identified 5.5 s after injection. After roughly 17.5 s, the saline peak could be identified in the time-activity curves (TACs).
At 0.25 s temporal resolution, the early-phase images visualized the first pass blood circulation of the rat heart, showing the 18F-FDG bolus flowing from the inferior vena cava to the right ventricle from 2.25 s. The tracer next circulated to the lungs via the pulmonary artery from 2.5 s, and then flowed to the left ventricle from 3.75 s.
The TACs clearly visualized the time dispersion between the right and left ventricles (1.25 s). This value can change for animals with cardiac disease, and the team plans to explore the benefit of fast temporal resolution PET for diagnosing cardiovascular and neurodegenerative diseases.
The researchers conclude that the TBS-PET scanner enables dynamic imaging with a nearly real-time frame rate, visualizing cardiac function and pulmonary circulation of a rat with 0.25 s temporal resolution, a feat that is not possible with conventional small-animal PET scanners.
“One drawback of the TBS-PET scanner is the relatively low spatial resolution of around 2.6 mm, which is limited by the relatively large crystal pitch of 2.85 mm,” says Kang. “To solve this issue, we are now developing a new small-animal PET scanner employing three-layer depth-encoding detectors with 0.8 mm crystal pitch, towards our final goal of sub-millimetre and sub-second temporal resolution PET imaging in rodent models.”
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A bumper crop of measurements of the expansion rate of the universe have stretched the Hubble tension as taut as it has ever been, with scientists grappling with trying to find a solution.
Over 500 researchers have come together in the “CosmoVerse” consortium to produce a new white paper that delves into the various cosmological tensions between theory and observation. These include the Hubble tension, which is the bewildering discrepancy in the expansion rate of the universe, referred to as the Hubble constant (H0).
Predictive measurements made by applying the standard model of cosmology to the cosmic microwave background (CMB) give H0 as 67.4 km/s/Mpc. In other words, every volume of space a million parsecs across (one parsec is 3.26 light years) should be expanding by 67.4 kilometres every second.
Yet that’s not what Hubble’s law – which tells us the expansion rate based on a given object’s velocity away from us and its distance – says, as demonstrated by the CosmoVerse White Paper.
“The paper’s been getting a lot of attention in our field,” Joe Jensen of Utah Valley University tells Physics World. “You can easily see that the vast majority of measurements fall around 73 km/s/Mpc, with varying uncertainties.”
There’s no known reason why local measurements of H0 (based on supernovae observations) should differ from the CMB measurement. This discrepancy leads to two possibilities. Either there are unknown systematic uncertainties in measurements that skew the results, or cosmology’s standard model is wrong and new physics is needed.
A lot at stake
The highest rung on the cosmic distance ladder is a type Ia supernova – a white dwarf explosion. They have a standardizable brightness that makes them perfect for judging how far away they are, based on their luminosity curve. These measurements are calibrated by lower rungs on the ladder, such as Cepheid variable stars or the peak brightness of red giant stars (referred to as the “tip of the red giant branch”, or TRGB).
If the tension is real, then different calibrators should still give the same result. One of the few outliers is found in a new paper published in The Astrophysical Journal by the Chicago–Carnegie Hubble Program (CCHP) led by the University of Chicago’s Wendy Freedman.
CCHP’s latest paper uses the TRGB to arrive at a best value of 70.39 km/s/Mpc when combining measurements from the James Webb Space Telescope (JWST) – which is able to better resolve red giant stars in other galaxies – with Hubble Space Telescope data.
The CCHP team argue that this result is in line with the CMB measurements and removes the tension. However, their conclusion has met opposition.
“Their result is sort of in the middle of the Hubble tension, so I’m surprised that they would say they rule it out,” Dan Scolnic, an astrophysicist at Duke University in the United States, tells Physics World.
At a meeting of the American Astronomical Society in January 2025, Scolnic declared that the Hubble tension was now a crisis. CCHP’s results do not dissuade him from this conclusion.
“For some reason they don’t include a number of supernovae in their sample that they could have,” says Scolnic. “Siyang Li [of Johns Hopkins University] led a paper [on which Scolnic is a co-author] that showed that if one uses their TRGB measurements, and the complete sample of supernovae, one goes back to higher H0.”
Freedman did not respond to Physics World‘s request for an interview.
Different approaches
Jensen has also led a team that recently conducted measurements of H0 using TRGB stars, but in a different way by looking for surface brightness fluctuations (SBF).
“SBF is a statistical method that measures the brightnesses of red giant stars even when they cannot be measured individually,” says Jensen.
Individual stars in galaxies cannot be resolved at great distance – their light blends together, and the more distant the galaxy, the smoother this blend is. We describe this blended light as the galaxy’s surface brightness, and fluctuations are statistical in nature and result from the discrete nature of stars.
In old elliptical galaxies, the surface brightness is dominated by red giant stars, which are evolved Sun-like stars. Measuring the SBF therefore provides a value for the TRGB, from which a distance can be determined.
Using JWST images to measure the SBF of 14 elliptical galaxies, then using those to calibrate the distances to 60 more distant ellipticals, and then using that calibration to determine H0, Jensen’s team arrived at a value of 73.8 km/s/Mpc.
“The reason that we don’t get the same answer [as CCHP] is that we are not using the same JWST calibrators, and we don’t use type Ia to measure H0,” says Jensen.
This contradicts CCHP’s main assertion, which is that there must be unknown systematic uncertainties in either the type Ia supernovae or the Cepheids. Jensen’s team use neither, yet still find a tension.
Perhaps the most convincing evidence for the tension comes from the TDCOSMO (time-delay cosmography) team, who utilize gravitationally lensed quasars to measure H0.
Quasars fluctuate in brightness over a matter of days. When light from a quasar takes paths of varying lengths around a lensing object, it produces multiple images that have time lags relative to one another. The expansion of space can extend this time delay, providing a completely independent measure of H0.
In 2019 the H0LiCOW project used six gravitational lenses to arrive at a value of 73.3 km/s/Mpc. This result came with some scepticism. So they formed the new TDCOSMO consortium and “went on a six-year journey to see if their original measurement was okay,” says Scolnic.
TDCOSMO’s final conclusion is 72.1 km/Mpc/s, strongly supporting the tension. However, in all these measurements there’s wriggle room from various known measuring uncertainties.
“It’s important to remember that the uncertainties put us in only mild disagreement,” says Jensen. “I expect that we will soon know if the disagreement can be explained by the mundane choices of calibration galaxies and processing techniques.”
If it cannot, then the inescapable conclusion is that there’s something wrong with our understanding of the universe. Figuring that out could be the next great quest in cosmology.
The Vera C. Rubin Observatory is poised to discover billions of new astronomical objects, revolutionizing understanding of everything from the history of the solar system to the workings of dark energy.
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The first spectacular images from the Vera C Rubin Observatory have been released today showing millions of galaxies and Milky Way stars and thousands of asteroids in exquisite detail.
Based in Cerro Pachón in the Andes, the Vera C Rubin Observatory contains the Legacy Survey of Space and Time (LSST) – the largest camera ever built. Taking almost two decades to build, the 3200 megapixel instrument forms the heart of the observatory’s 8.4 m Simonyi Survey Telescope.
The imagery released today, which took just 10 hours of observations, is a small preview of the Observatory’s upcoming 10-year scientific mission.
The image above is of the Trifid and Lagoon nebulas. This picture combines 678 separate images taken by the Vera C. Rubin Observatory in just over seven hours of observing time. It reveals otherwise faint or invisible details, such as the clouds of gas and dust that comprise the Trifid nebula (top right) and the Lagoon nebula, which are several thousand light-years away from Earth.
The image below is of the Virgo cluster. It shows a small section of the Virgo cluster, featuring two spiral galaxies (lower right), three merging galaxies (upper right) and several groups of distant galaxies.
Cosmic expanse: Vera C. Rubin Observatory’s view of the Virgo cluster. (Courtesy: NSF-DOE Vera C. Rubin Observatory)
Star mapper
Later this year, the Vera C Rubin Observatory, which is funded by the National Science Foundation and the Department of Energy’s Office of Science, will begin a decade-long survey of the southern hemisphere sky.
The LSST will take a complete picture of the southern night sky every 3-4 nights. It will then replicate this process over a decade to produce almost 1000 full images of sky.
This will be used to plot the positions and measure the brightness of objects in the sky to help improve our understanding of dark matter and dark energy. It will examine 20 billion galaxies as well as produce the most detailed star map of the Milky Way, imaging 17 billion stars and cataloguing some six million small objects within our solar system including asteroids.
Cosmic pioneer
On top of the world: Later this year, the Vera C Rubin Observatory will begin a decade-long survey of the southern hemisphere sky. (Courtesy: NSF-DOE Vera C. Rubin Observatory)
The observatory is named in honour of the US astronomer Vera C. Rubin. In 1970, working with Kent Ford Jr, they observed that outer stars orbiting in the Andromeda galaxy were all doing so at the same speed.
Examining more galaxies still, they found that their rotation curves – the orbital speed of visible stars within the galaxy compared with their radial distance to the galaxy centre – contradicted Kepler’s law.
They also found that stars near the outer edges of the galaxies were orbiting so fast that they should be falling apart.
Rubin and Ford Jr’s observation led them to predict that there was some mass, dubbed “dark matter”, inside the galaxies responsible for the anomalous motions, something their telescopes couldn’t see but was there in quantities about six times the amount of the luminous matter present.
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