Astronomy
Being in space makes it harder for astronauts to think quickly
Starship’s Booster (and Donald Trump) Make a Splash With Sixth Flight Test
SpaceX’s Starship launch system went through its sixth flight test today, and although the Super Heavy booster missed out on being caught back at its launch pad, the mission checked off a key test objective with President-elect Donald Trump in the audience.
Trump attended the launch at SpaceX’s Starbase complex in the company of SpaceX CEO Elon Musk, who has been serving as a close adviser to the once and future president over the past few months. In a pre-launch posting to his Truth Social media platform, Trump wished good luck to “Elon Musk and the Great Patriots involved in this incredible project.”
President Trump has arrived to watch the SpaceX launch with @elonmusk! ? pic.twitter.com/D5awPUUQTC
— Trump War Room (@TrumpWarRoom) November 19, 2024Starship is the world’s most powerful rocket, with 33 methane-fueled Raptor engines providing more than 16 million pounds of thrust at liftoff. That’s twice the power of the Saturn V rocket that sent Americans to the moon in the 1960s and early ’70s. The two-stage rocket stands 121 meters (397 feet) tall, with a 9-meter-wide (30-foot-wide) fairing.
Super Heavy had an on-time launch at 4 p.m. CT (22:00 UTC) and was set up to fly itself back to the launch tower to be caught by the giant “Mechazilla” arms that were successfully used during last month’s flight test. But four minutes after liftoff, mission controllers said the booster had to be diverted instead to make a soft splashdown in the Gulf of Mexico.
In a recap of the flight, SpaceX said that “automated health checks of critical hardware on the launch and catch tower triggered an abort of the catch attempt.”
“It was not guaranteed that we would be able to make a tower catch today,” launch commentator Kate Tice said during today’s webcast. “So, while we were hoping for it … the safety of the teams and the public and the pad itself are paramount. We are accepting no compromises in any of those areas.”
While the booster settled majestically into the Gulf, the Starship second stage — known as Ship for short — continued on a track that sent it as high as 190 kilometers (120 miles). A plush banana was placed in Ship’s cargo bay as a zero-gravity indicator, and Tice wore a T-shirt bearing the words “It’s Bananas!” to play off the lighthearted theme.
Ship successfully relit one of its methane-fueled Merlin engines while in space, which was a key objective for today’s suborbital test. Relighting the engines under such conditions will be required in the future for Ship’s orbital maneuvers.
A little more than an hour after launch, Ship’s engines fired for a final time to make a controlled splashdown in the Indian Ocean. The daylight visuals, plus other data collected during the flight, will help SpaceX’s team fine-tune Starship’s design for future tests.
SpaceX plans to use Starship to accelerate deployment of its Starlink broadband satellites, as well as to fly missions beyond Earth orbit. The company has a $2.9 billion contract from NASA to provide a version of Starship that’s customized for lunar landings, starting as early 2026. And Musk has said Starship could take on uncrewed missions starting that same year — with the first crewed mission set for launch in 2028 if everything goes right.
NASA Administrator Bill Nelson referred to those future flights in a message on Musk’s X social-media platform:
Congrats to @SpaceX on Starship's sixth test flight. Exciting to see the Raptor engine restart in space—major progress towards orbital flight.
Starship’s success is #Artemis’ success. Together, we will return humanity to the Moon & set our sights on Mars. pic.twitter.com/tuwpGOvT9S
Check out these other postings tracking the progress of the flight test:
With data and flight learnings as our primary payload, Starship’s sixth flight test once again delivered ? https://t.co/oIFc3u9laE pic.twitter.com/O6ZKThQRr6
— SpaceX (@SpaceX) November 20, 2024Super Heavy initiates its landing burn and softly splashes down in the Gulf of Mexico pic.twitter.com/BZ3Az4GssC
— SpaceX (@SpaceX) November 19, 2024Starship’s Raptor engine burn is complete and Starship has entered a coast phase pic.twitter.com/xJHlg2eDTs
— SpaceX (@SpaceX) November 19, 2024Live views of Earth from Starship pic.twitter.com/3rgsHSj2km
— SpaceX (@SpaceX) November 19, 2024Starship preparing to splash down in the Indian Ocean pic.twitter.com/EN9jibr07l
— SpaceX (@SpaceX) November 19, 2024Splashdown confirmed! Congratulations to the entire SpaceX team on an exciting sixth flight test of Starship! pic.twitter.com/bf98Va9qmL
— SpaceX (@SpaceX) November 19, 2024The post Starship’s Booster (and Donald Trump) Make a Splash With Sixth Flight Test appeared first on Universe Today.
Einstein’s theories tested on the largest scale ever – he was right
Einstein’s theories tested on the largest scale ever – he was right
'Mind-blowing' dark energy instrument results show Einstein was right about gravity — again
Trump watches SpaceX launch Starship's 6th test flight (photos)
Pentagon UFO chief tells Senate 'very anomalous objects' need careful study (video)
SpaceX Starship launches banana to space, skips giant rocket catch on 6th test flight (video, photos)
Starship live: Watch Musk launch sixth Starship test as Trump attends
Starship live: Watch Musk launch sixth Starship test as Trump attends
On This Day: Apollo 12 Lands on the Moon
India's Chandrayaan-2 moon orbiter avoids collision with South Korea's Danuri spacecraft
The Strange Pulsar at the Center of the Crab Nebula
Thanks to the Hubble Space Telescope, we all have a vivid image of the Crab Nebula emblazoned in our mind’s eyes. It’s the remnant of a supernova explosion Chinese astronomers recorded in 1056. However, the Crab Nebula is more than just a nebula; it’s also a pulsar.
The Crab Pulsar pulsates in an unusual ‘zebra’ pattern, and an astrophysicist at the University of Kansas thinks he’s figured out why.
When massive stars explode as supernovae, they leave behind remnants: either a stellar-mass black hole or a neutron star. SN 1054 left behind the latter. The neutron star is highly magnetized and spins rapidly, emitting beams of electromagnetic radiation from its poles. As it spins, the radiation is intermittently directed towards Earth, making it visible to us. In this case, it’s called a pulsar.
Pulsars are complex objects. They’re extremely dense and can pack up to three solar masses of material into a sphere as small as 30 km in diameter. Their magnetic fields are millions of times stronger than Earth’s, they can rotate hundreds of times per second, and their immense gravity warps space-time. And their cores are basically huge atomic nuclei.
One result of their complexity is their radio emissions, and this is especially true of the Crab Pulsar.
Pulsars are known for their main pulse (MP), but they also emit other pulses that are more difficult to detect. In 2007, radio astronomers Hankins and Eilek discovered a strange pattern in the Crab Pulsar’s high-frequency radio emissions. This is the only pulsar known to produce these patterns between the pulsar’s main pulse (MP) and its intermittent pulse (IP).
“The mean profile of this star is dominated by a main pulse (MP) and an interpulse (IP),” Eilek and Hankins wrote in their paper. However, there are two additional pulses called HFC1 and HFC2 that create the zebra pattern.
This figure shows the mean profile of the Crab pulsar over a wide range of frequencies. The MP and IP are shown by dashed lines at pulse phases 70° and 215°. However, between 4.7 and 8.4 GHz, the IP is offset from the IP at lower and higher frequencies. This constitutes the Crab Pulsar’s ‘zebra’ pattern. Two new high-frequency components also appear (labelled HFC1 and HFC2). Image Credit: Moffett & Hankins 1996.Nobody has succeeded in explaining this unusual pattern. However, new research published in Physical Review Letters may finally explain it. The author is Mikhail Medvedev, who specializes in Theoretical Astrophysics at the University of Kansas. His research is “Origin of Spectral Bands in the Crab Pulsar Radio Emission.”
Medvedev says that the Crab Pulsar’s plasma-filled magnetosphere acts as a diffraction screen to produce the zebra pattern. This can explain the band spacing, the high polarization, the constant position angle, and other characteristics of the emissions.
This figure shows the overall geometry of the crab pulsar system. The red star is the pulsar. Its emissions pass through the plasma-filled magnetosphere, which acts as a diffraction screen, producing the zebra pattern of pulses. Image Credit: Medvedev 2024.A typical pulsar emits radio emissions from its poles, as shown in the figure below. They sometimes emit two signals per rotation period, one radio and one high frequency. They appear in a different phase of the rotation, with the higher frequency emission produced outside the light cylinder, the region where linear speed approaches the speed of light.
This figure shows how a standard pulsar emits radio emissions. Electrons and positrons are accelerated through one of the gaps in the magnetosphere. They stream along the open magnetic field lines and emit coherent radio emissions from the poles. Image Credit: National Radio Astronomy Observatory.But the Crab Pulsar is different.
“The Crab pulsar is, in contrast, very special. Its radio main pulse and interpulse are coincident in phase with high-energy emission, indicating the same emission region,” Medvedev explains.
Medvedev explains that the High-Frequency Interpulse (HFIP) produced by the diffraction effect creates the zebra pattern. “The spectral pattern of the high-frequency interpulse (HFIP), observed between about
?~5 and ?~30 GHz is remarkably different and represents a sequence of emission bands resembling the
“zebra” pattern,” he writes.
Medvedev’s proposed model has an additional benefit. He says it can be used to perform tomography on pulsars to uncover more details about their powerful magnetospheres.
“The model allows one to perform “tomography” of the pulsar magnetosphere,” he writes.
“We predict that this HFIP properties can also be observed in other pulsars if their radio and high energy emission are in phase. This would happen if the radio emission is produced in the outer magnetosphere as opposed to the “normal” emission from the polar region,” Medvedev explains.
This composite image of the Crab Nebula features X-rays from Chandra (blue and white), optical data from Hubble (purple), and infrared data from Spitzer (pink). Chandra has repeatedly observed the Crab since the telescope was launched into space in 1999. Image Credit: X-ray: NASA/CXC/SAO; Optical: NASA/STScI; Infrared: NASA-JPL-CaltechMedvedev says his model can also explain the HFC1 and HFC2 in the Crab Pulsar’s emissions spectrum. They’re also artifacts of his proposed diffraction model. “We propose that these high-frequency components are the reflections off the magnetosphere of the same source producing the diffracted HFIP,” he explains.
“To conclude, we propose a model, which explains the peculiar spectral band structure (the zebra pattern) of the high-frequency interpulse of the Crab pulsar radio emission,” Medvedev writes.
The post The Strange Pulsar at the Center of the Crab Nebula appeared first on Universe Today.
‘Bomb Cyclone’ and Atmospheric River Will Bring Extreme Weather to U.S. West Coast
A major windstorm and an atmospheric river are set to unleash a “firehose” of precipitation from California to British Columbia
SabersPro Luke lightsaber review: "A premium, supersaver saber for duellists"
Trees Alone Can’t Stop Climate Change
Forests absorb planet-warming pollution, but world leaders shouldn’t include them in plans to reach net-zero greenhouse gas emissions, a new study recommends
