October 5, 2024
Evrim Yazgin
Cosmos science journalist
NASA’s James Webb Space Telescope has discovered a unique supernova which has helped measure the Hubble constant – the rate at which the universe is expanding.
Several research papers have been published from the observations of the supernova, dubbed Supernova H0pe. These papers can be accessed from this NASA blog post announcing the discovery
Supernovae are the bright, powerful explosions caused by the violent death of a massive star.
“It all started with one question by the team: ‘What are those 3 dots that weren’t there before? Could that be a supernova?’” says University of Arizona astronomer Brenda Frye.
The points of light were not visible when the Hubble telescope imaged the same cluster in 2015.
“Initial analyses confirmed that these dots corresponded to an exploding star, one with rare qualities,” Frye adds. “First, it’s a Type Ia supernova, an explosion of a white dwarf star. This type of supernova is generally called a ‘standard candle,’ meaning that the supernova had a known intrinsic brightness. Second, it is gravitationally lensed.”
Gravitational lensing is a consequence of the characteristics of the universe described by Einstein’s general theory of relativity. Massive objects – like galaxies – warp space-time around them, bending the trajectory of light.
When objects line up, this creates a lensing effect which can magnify more distant objects.
In this case, the lens consists of 3 galaxies sitting between us and the supernova, bending the supernova’s light into 3 images.
“This is similar to how a trifold vanity mirror presents 3 different images of a person sitting in front of it,” Frye explains. “Since each path had a different length, and light travelled at the same speed, the supernova was imaged in this Webb observation at 3 different times during its explosion.”
“Trifold supernova images are special: The time delays, supernova distance, and gravitational lensing properties yield a value for the Hubble constant. The supernova was named SN H0pe since it gives astronomers hope to better understand the universe’s changing expansion rate.
SN H0pe is tethered to a galaxy which existed about 3.5 billion years after the Big Bang. It is the most distant Type Ia supernovae observed.
Researchers around the world made independent observations of SN H0pe using models of how the galaxies might have lensed the light from the supernovae.
“Since the Type Ia supernova is a standard candle, each lens model was ‘graded’ by its ability to predict the time delays and supernova brightnesses relative to the true measured values,” Frye says.
“The team reports the value for the Hubble constant as 75.4 kilometres per second per megaparsec, plus 8.1 or minus 5.5. [One parsec is equivalent to 3.26 light-years of distance.] This is only the second measurement of the Hubble constant by this method, and the first time using a standard candle,” Frye adds.
“This is one of the great Webb discoveries, and is leading to a better understanding of this fundamental parameter of our universe.”
“Our team’s results are impactful: The Hubble constant value matches other measurements in the local universe, and is somewhat in tension with values obtained when the universe was young,” she adds.
3-member Shenzhou-18 crew, currently aboard China’s Tiangong space station, to return in late October after 6-month mission
Serdar Dincel |05.10.2024 - TRT/AA
ISTANBUL
Space missions in China are gathering steam with a new manned mission set for later this month when the three-member crew of Shenzhou-18 returns home.
China Manned Space Agency (CMSA) released the exterior design of its red-and-white suit space suit last weekend, during a ceremony in southwestern Chongqing.
CMSA said the new Shenzhou-19 crew members will take control of space operations from the Shenzhou-18 taikonauts who are preparing to return home after conducting six months of research in space.
Ye Guangfu, teammates Li Cong and Li Guangsu of the Shenzhou-18 crew are currently aboard China's indigenously built Tiangong space station.
Ye is a fighter pilot and veteran astronaut who took part in the Shenzhou-13 mission in 2021.
The trio launched on April 25.
Shenzhou-18 is the 32nd mission of China's manned space program and the third manned mission during the operation and development stage of China's space station.
The Shenzhou 19 flight will mark China’s 14th crewed spaceflight and the 19th of the Shenzhou program.
The new crew that is set to be launched from the Jiuquan Satellite Launch Center in Inner Mongolia is composed of three People's Liberation Army Astronaut Corps, locally known as taikonauts, on the eighth flight to the Tianhe core module.
Tianhe core is the first module of the Tiangong space station.
China unveiled the name of its new spacecraft in February that will take astronauts on a lunar mission expected by the end of the decade.
The Mengzhou spacecraft and Lan Yue lunar lander will be China’s moon mission.
The white moon-landing spacesuit, expected to be ready before 2030, was showcased at the third Spacesuit Technology Forum held Sept. 28 by the China Astronaut Research and Training Center in Chongqing.
The red stripes on the upper limbs are inspired by the ribbons of the renowned flying apsaras from Dunhuang art, while the stripes on the lower limbs resemble the flames of a rocket launch.
It is designed to protect against the harsh thermal environment and lunar dust while the suit’s helmet features a panoramic, anti-glare visor, in addition to a separate long and short focal length camera.
The suit has a multi-functional integrated control console on the chest.
Chinese state media said the suit draws inspiration from traditional Chinese armor embodying "resilience, strength, and dignity, reflecting the courage and pioneering spirit of the Chinese people."
Adding more feathers to its cap, China's Chang'e-6 mission successfully returned in June, bringing 1,935.3 grams of soil and rocks, the first-ever from the far side of the moon.
In recent weeks, however, there have been a few rocket launch failures.
No spaceplane in the payload, but it won't be a wasted mission
Fri 4 Oct 2024
Updated United Launch Alliance's (ULA) Vulcan Centaur is ready to blast off from Florida this morning, the second flight to space for the rocket.
While the mission, dubbed Cert-2, was originally set to carry Sierra Space's Dream Chaser, delays with the spaceplane have meant that ULA opted to lift-off with an inert payload instead.
ULA needs to get that second attempt under its belt to certify the vehicle for lucrative US national security payloads.
The Vulcan Centaur is ULA's replacement for the Atlas V and Delta IV launchers. Its maiden voyage – which ran later than scheduled, in part due to the slower delivery of the Blue Origin BE-4 engines used to power the first stage – went ahead in January 2024. Named Cert-1, the rocket was carrying Astrobotic's Peregrine lunar lander.
After giving up the wait for Dream Chaser, which should arrive at some point in 2025, ULA is instead going to use a mass simulator along with some experiments and demonstrations to ease the vehicle's passage to US Space Force certification.
According to ULA boss Tory Bruno, ULA waited for Sierra Space until "the last minute," which meant the company was unable to integrate payloads from other customers keen on a ride to orbit.
The variant of the Vulcan Centaur being launched today features a pair of solid rocket boosters strapped onto the first stage, which is powered by two BE-4 engines, each producing 550,000 lbf (2.4 meganewtons) of sea level thrust. Each solid rocket booster contributes an additional 459,600 lbf (2.044 meganewtons) of thrust at lift-off.SpaceX's
Dream Chaser mini-shuttle set to take flight at last
Sierra Space bursts full-scale inflatable space habitat module
Peregrine bows out with a bang as SLIM aims for Moon's rocky runway
According to Bruno, ULA decided on a heliocentric disposal of the upper stage – leaving it in an orbit around the Sun – after some "experimental maneuvers."
If all goes well, ULA aims to launch two more Vulcan Centaur rockets in 2024 before ramping up the cadence in 2025. ULA is planning for an ambitious 20 launches, split between the outgoing Atlas V and the Vulcan Centaur. These aren't SpaceX-level numbers, but considerably more than ULA has managed in the past.
The three-hour launch window opens at 1000 UTC, and there is currently an 80 percent chance that the weather will cooperate. A Wet Dress Rehearsal (WDR) earlier this week, where the rocket was fueled and a countdown performed to just before engine ignition, went well.
The next step will be to ignite the engines and stand back a few hours from now. ®
Updated to add at 1232 UTC, October 4
After a slight delay, the Vulcan Centaur successfully lifted off from Space Launch Complex-41 at 1125 UTC. Five minutes and 30 seconds later, the first stage was jettisoned, and the Centaur V upper stage took over to send itself and the inert payload into an initial parking orbit around the Earth.
Wales says no to space wars
Dylan Lewis-Rowlands from CND Cymru explains why opposition is growing to a proposed military site in Wales.
When the Ministry of Defence announced Brawdy in Pembrokeshire as their preferred site for a deep space radar site, we were disappointed, but not surprised. Following centuries of Welsh land and air being militarised for the benefit of the state, the notion that the new frontier for war – space – will be fought partially from Wales probably came naturally to those over in the so-called MOD.
What might’ve been more surprising to us is where they chose to site this element of the Deep Space Advanced Radar Capability (DARC) programme – in a national park noted for its extraordinary natural beauty, where the economy is propped up by tourism and leisure. It is also a site that has seen opposition to development before. In the late 80s and early 90s, a campaign known as PARC – Pembrokeshire Against RADAR Campaign – forced the Thatcher government to very publicly cancel a RADAR development in Cawdor due to overwhelming public opposition. The stage is set therefore for a rematch: the UK government vs the new PARC against DARC.
The DARC development poses many threats to Pembrokeshire and Cymru in addition to the political. Such a massive development could easily choke a local economy so reliant on tourism and leisure. A site like this, constantly broadcasting signals into the sky and space, lit up so brightly, could devastate local wildlife, including the endangered bird the Manx Shearwater. The development also creates a definitive military target – with DARC being the most advanced space tracking facility available to the Americans (yes- it’ll be run by America), it is a logical target for attack for the opponents of the dying imperial hegemon.
I’ve only briefly outlined some of the threats DARC poses – there are many more. But we hope to stop the proposals in their tracks. At a local ‘PR’ event that could only be described as an unmitigated disaster for the MOD, local campaigners and activists turned out to demonstrate their opposition. At a packed event a few months prior, even more came to the launch of the PARC against DARC campaign.
This proposal, much like the proposal of the 80s, can be defeated. But it requires us to show up. It requires peace campaigners and local communities to unite as before. We will not lie down and accept this. We will turn up to future PR events, we will oppose the granting of planning permission, we will show just how ferociously Cymru yearns to be a Nation of Peace. I hope you will join us.
- Dylan Lewis-Rowlands is the National Secretary of CND Cymru
- For more information on the campaign see www.parcagainstdarc.com
- If you support Labour Outlook’s work amplifying the voices of left movements and struggles here and internationally, please consider becoming a supporter on Patreon.
At T-plus 35 minutes and three seconds, the engines of the Centaur V upper stage were fired up again to take the upper stage and its inert payload to deep space and into an orbit around the Sun.
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