Astrophysicists from Northwestern University in Illinois have discovered that the universe's youngest galaxies, captured by the James Webb Space Telescope (JWST), are not as vast as their brightness suggests.
This challenges previous perceptions about these galaxies, helping our understanding of the universe shortly after the Big Bang, the scientists say.
In their study, the researchers were initially surprised by their excessive brightness.
They said it appeared as if a toddler had matured into an adult within mere years, prompting concerns about our understanding of the cosmos.
Prof Claude-Andre Faucher-Giguere, Northwestern's senior researcher, said: “The discovery of these galaxies was a big surprise because they were substantially brighter than anticipated.”
The question of how these galaxies had matured so quickly after the Big Bang the arose.
The team employed new simulations to solve this cosmic riddle.
While a galaxy's luminosity usually reflects its mass, the team found that smaller galaxies can also shine intensely due to sporadic bursts of star formation,
Research lead Dr Guochao Sun noted: “If star formation happens in bursts, it will emit flashes of light. That is why we see several very bright galaxies.”
The era called the “cosmic dawn”, ranging from roughly 100 million to 1 billion years after the Big Bang, witnessed the birth of the universe's first stars and galaxies.
Our knowledge about this period was limited until the launch of the space telescope.
“The JWST brought us a lot of knowledge about cosmic dawn,” Dr Sun said.
The study team employed intricate computer simulations to recreate the conditions after the Big Bang.
These simulations spotlighted a phenomenon called “bursty star formation” – an alternating pattern of intense star birth followed by extended periods of star-formation dormancy.
“Bursty star formation is particularly prevalent in low-mass galaxies,” Prof Faucher-Giguere said, detailing the cyclic nature of stars forming, then exploding as supernovae, leading to new formations.
Significantly, the simulations aligned with the JWST's observations regarding the brightness of cosmic dawn galaxies.
This research not only provides the first evidence through detailed computer simulations that bursty star formation could account for the luminance of galaxies at cosmic dawn but also supports our standard model of the universe.
Emphasising the importance of recent star formation in determining galaxy brightness, Prof Faucher-Giguere concluded, “Most of the light in a galaxy comes from the most massive stars.
"The brightness of a galaxy is more directly related to how many stars it has formed in the last few million years than the mass of the galaxy as a whole.”
The study called 'Bursty star formation naturally explains the abundance of bright galaxies at cosmic dawn' was supported by Nasa and the National Science Foundation, and published in the Astrophysical Journal Letters.
MATCH INFO
Alaves 1 (Perez 65' pen)
Real Madrid 2 (Ramos 52', Carvajal 69')
Islamophobia definition
A widely accepted definition was made by the All Party Parliamentary Group on British Muslims in 2019: “Islamophobia is rooted in racism and is a type of racism that targets expressions of Muslimness or perceived Muslimness.” It further defines it as “inciting hatred or violence against Muslims”.
UAE currency: the story behind the money in your pockets
How tumultuous protests grew
- A fuel tax protest by French drivers appealed to wider anti-government sentiment
- Unlike previous French demonstrations there was no trade union or organised movement involved
- Demonstrators responded to online petitions and flooded squares to block traffic
- At its height there were almost 300,000 on the streets in support
- Named after the high visibility jackets that drivers must keep in cars
- Clashes soon turned violent as thousands fought with police at cordons
- An estimated two dozen people lost eyes and many others were admitted to hospital
Earth under attack: Cosmic impacts throughout history
- 4.5 billion years ago: Mars-sized object smashes into the newly-formed Earth, creating debris that coalesces to form the Moon
- 66 million years ago: 10km-wide asteroid crashes into the Gulf of Mexico, wiping out over 70 per cent of living species – including the dinosaurs.
- 50,000 years ago: 50m-wide iron meteor crashes in Arizona with the violence of 10 megatonne hydrogen bomb, creating the famous 1.2km-wide Barringer Crater
- 1490: Meteor storm over Shansi Province, north-east China when large stones “fell like rain”, reportedly leading to thousands of deaths.
- 1908: 100-metre meteor from the Taurid Complex explodes near the Tunguska river in Siberia with the force of 1,000 Hiroshima-type bombs, devastating 2,000 square kilometres of forest.
- 1998: Comet Shoemaker-Levy 9 breaks apart and crashes into Jupiter in series of impacts that would have annihilated life on Earth.
-2013: 10,000-tonne meteor burns up over the southern Urals region of Russia, releasing a pressure blast and flash that left over 1600 people injured.
The five pillars of Islam
1. Fasting
2. Prayer
3. Hajj
4. Shahada
5. Zakat
Skewed figures
In the village of Mevagissey in southwest England the housing stock has doubled in the last century while the number of residents is half the historic high. The village's Neighbourhood Development Plan states that 26% of homes are holiday retreats. Prices are high, averaging around £300,000, £50,000 more than the Cornish average of £250,000. The local average wage is £15,458.
Stormy seas
Weather warnings show that Storm Eunice is soon to make landfall. The videographer and I are scrambling to return to the other side of the Channel before it does. As we race to the port of Calais, I see miles of wire fencing topped with barbed wire all around it, a silent ‘Keep Out’ sign for those who, unlike us, aren’t lucky enough to have the right to move freely and safely across borders.
We set sail on a giant ferry whose length dwarfs the dinghies migrants use by nearly a 100 times. Despite the windy rain lashing at the portholes, we arrive safely in Dover; grateful but acutely aware of the miserable conditions the people we’ve left behind are in and of the privilege of choice.
GIANT REVIEW
Starring: Amir El-Masry, Pierce Brosnan
Director: Athale
Rating: 4/5
Key recommendations
- Fewer criminals put behind bars and more to serve sentences in the community, with short sentences scrapped and many inmates released earlier.
- Greater use of curfews and exclusion zones to deliver tougher supervision than ever on criminals.
- Explore wider powers for judges to punish offenders by blocking them from attending football matches, banning them from driving or travelling abroad through an expansion of ‘ancillary orders’.
- More Intensive Supervision Courts to tackle the root causes of crime such as alcohol and drug abuse – forcing repeat offenders to take part in tough treatment programmes or face prison.
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The Al Barzakh Festival takes place on Wednesday and Thursday at 7.30pm in the Red Theatre, NYUAD, Saadiyat Island. Tickets cost Dh105 for adults from platinumlist.net
