Archive for the ‘space’ category: Page 7

Aug 11, 2023

Webb sheds light on Earendel, the most distant star in the universe

Posted by in category: space

Last year, the Hubble Space Telescope made headlines by detecting the most distant star ever seen, a luminary from the universe’s first billion years named “Earendel.” Now, NASA’s James Webb Space Telescope has uncovered mesmerizing details about this intriguing star.

“The Hubble provided us a glimpse of Earendel, but the James Webb Space Telescope is now offering us a deep dive,” said NASA. “These observations not only enlighten us about the star’s nature but also about its host galaxy, the Sunrise Arc, and possibly about the early universe itself.”

Earendel is no ordinary star. Webb’s NIRCam (Near-Infrared Camera) instrument paints a portrait of a massive B-type star, sizzling at temperatures twice as scorching as our Sun and radiating with a luminosity a million times more intense.

Aug 10, 2023

Want To Win A Free Ticket To Space? Apply Now With Space For Humanity

Posted by in category: space

You can keep saving up to buy a six-figure ticket to space, or try this new Citizen Astronaut Program to earn your spot through passion and commitment to positive change.

Aug 10, 2023

What is a ‘spacelike surface’ in relativity?

Posted by in category: space

I am studying Noether’s theorem in field theory and I am not understanding what spacelike-surfaces mean. I will reproduce the bit of the argument below that contains the term “spacelike-sufaces” in the context I am not understanding.

There will be a conserved ccurrent for each group generator $a$. Each will result in a conserved charge (that is, an integral of motion). To see this, take in spacetime a volume unbounded in the space-like direction, but limited in time by two space-like surfaces $w_1$ and $w_2$. Integrating $\partial_{\mu} J^{\mu}_a=0$ over this volume, we get an integral over the boundary surface, composed of $w_1$, $w_2$ and the time-like boundaries supposed to be at infinity. If we now suppose the current to be zero at infinity on these boundaries, we remain with.

$$\int_{w_1}d\sigma_{\mu} J^{\mu}_a=\int_{w_2}d\sigma_{\mu} J^{

Aug 9, 2023

NASA just found a question mark in space. What exactly is it?

Posted by in category: space

The hints pointing to two galaxies are found in the question mark’s strange shape. There are two brighter spots, one in the curve and the other in the dot, which could be the galactic nuclei, or the centers of the galaxies, Britt says. The curve of the question mark might be the “tails” being stripped off as the two galaxies spiral toward each other.

“It’s very cute. It’s a question mark … But you can find the colons and semicolons, and any other punctuation mark, because you have 10,000 little smudges of light in each image taken every half hour,” says David Helfand, an astronomer at Columbia University. The sheer number of shining objects we find are bound to create some serendipitous images, and our brains have evolved to find those patterns, he says.

Astronomers have seen similar objects closer to home. Two merging galaxies captured by the Hubble Space Telescope in 2008 also look like a question mark, just turned 90 degrees.

Aug 9, 2023

After 15 years, pulsar timing yields evidence of cosmic background gravitational waves

Posted by in categories: physics, space

The universe is humming with gravitational radiation—a very low-frequency rumble that rhythmically stretches and compresses spacetime and the matter embedded in it.

That is the conclusion of several groups of researchers from around the world who simultaneously published a slew of journal articles in June describing more than 15 years of observations of millisecond pulsars within our corner of the Milky Way galaxy. At least one group—the North American Nanohertz Observatory for Gravitational Waves (NANOGrav) collaboration—has found compelling evidence that the precise rhythms of these pulsars are affected by the stretching and squeezing of spacetime by these long-wavelength .

“This is key evidence for gravitational waves at very low frequencies,” says Vanderbilt University’s Stephen Taylor, who co-led the search and is the current chair of the collaboration. “After years of work, NANOGrav is opening an entirely new window on the gravitational-wave universe.”

Aug 9, 2023

NASA regains contact with Voyager 2 after it went dark for two weeks

Posted by in category: space

NASA has reestablished connection with Voyager 2 after a tense two weeks of not hearing anything from the probe. On July 21st, the agency lost contact with Voyager 2 following a series of planned commands that mistakenly pointed it two degrees away from our planet. While it is scheduled to automatically reset its orientation on October 15th, it’s not surprising that NASA scientists didn’t just wait for that date to know whether the spacecraft is still running. Voyager 2 was launched way back in 1977, and it’s one of the only two probes sending us back valuable data on interstellar space.

For a few days after July 21st, NASA wasn’t even sure what the spacecraft’s condition was. It wasn’t until August 1st that multiple ground antennas from the Deep Space Network (DSN) were able to detect a carrier signal from the probe. A carrier signal is what a spacecraft uses to beam data back to the ground, but NASA said the one DSN detected was too weak to be able to transmit any information. Still, it was enough to confirm that Voyager 2 was still working and that it hadn’t deviated from its trajectory.

Instead of simply waiting for October, Voyager’s ground team decided to take action. They concocted a plan to “shout” a command to the spacecraft across over 12.3 billion miles of space using the DSN, telling it to turn its antenna back to Earth. The whole process illustrated just how vast outer space truly is: It took 18.5 hours for that message to reach the probe, and another 18.5 hours for NASA to start receiving science and telemetry data again, indicating that Voyager 2 had received the command.

Aug 9, 2023

Astronomers Confirm The Faintest Galaxy in The Known Universe

Posted by in categories: particle physics, space

The Universe we live in is a transparent one, where light from stars and galaxies shines bright against a clear, dark backdrop.

But this wasn’t always the case – in its early years, the Universe was filled with a fog of hydrogen atoms that obscured light from the earliest stars and galaxies.

Continue reading “Astronomers Confirm The Faintest Galaxy in The Known Universe” »

Aug 9, 2023

Research investigates eclipsing binary CSS J003106.8+313347

Posted by in categories: materials, space

Using a private observatory, astronomers have performed the first photometric study of a peculiar W UMa-type binary known as CSS J003106.8+313347. Results of the study, published July 27 on the preprint server arXiv, shed more light on the properties of this system.

In general, W Ursae Majoris-type, or W UMa-type binaries (EWs) are eclipsing binaries with a short orbital period (below one day) and continuous light variation during a cycle. They are composed of two with similar temperature and luminosity, sharing a common envelope of material and are thus in contact with one another. Therefore, they are often dubbed “contact binaries.”

Located some 4,900 away, CSS J003106.8+313347 is an EW with an apparent magnitude of 14.73. The orbital period of the system is estimated to be approximately 0.344 days.

Aug 9, 2023

Space Solar Power Feasibility Demonstrated by Caltech-Launched Satellite

Posted by in categories: solar power, space, sustainability

A satellite demonstrator showed that energy collected from solar panels in space can be beamed to Earth using diffuse microwaves.

Aug 9, 2023

Cerebras Builds Massive AI Supercomputer

Posted by in categories: food, robotics/AI, space, supercomputing

That’s how Andrew Feldman, CEO of Silicon Valley AI computer maker Cerebras, begins his introduction to his company’s latest achievement: An AI supercomputer capable of 2 billion billion operations per second (2 exaflops). The system, called Condor Galaxy 1, is on track to double in size within 12 weeks. In early 2024, it will be joined by two more systems of double that size. The Silicon Valley company plans to keep adding Condor Galaxy installations next year until it is running a network of nine supercomputers capable of 36 exaflops in total.

If large-language models and other generative AI are eating the world, Cerebras’s plan is to help them digest it. And the Sunnyvale, Calif., company is not alone. Other makers of AI-focused computers are building massive systems around either their own specialized processors or Nvidia’s latest GPU, the H100. While it’s difficult to judge the size and capabilities of most of these systems, Feldman claims Condor Galaxy 1 is already among the largest.

Condor Galaxy 1—assembled and started up in just 10 days—is made up of 32 Cerebras CS-2 computers and is set to expand to 64. The next two systems, to be built in Austin, Texas, and Ashville, N.C., will also house 64 CS-2s each.

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