Latest news with #astronomy
CBC
13 hours ago
- Climate
- CBC
Clearest images of sun's atmosphere yet show coronal rain and dancing plasma
New images that are the highest resolution ever taken of the surface of the sun and its corona will help scientists solve mysteries about how storms on the sun develop. This could improve space weather forecasts and help prevent disruptions to technology on Earth. The images were part of a recent study published in Nature Astronomy. Anyone who has seen a total eclipse of the sun has been witness to the glowing halo around our star known as the corona. This envelope of extremely hot gas extends millions of kilometres out into space and is where violent eruptions take place. These bursts of electrically charged gas can blow off the sun and reach all the way to Earth, affecting satellites and power grids. This glosses over one of the big mysteries about the sun. Scientists have not been able to entirely understand why the corona can be many times hotter than the surface of the sun itself. Something is pumping energy into the sun's atmosphere. One problem has been the dearth of observations of the corona at its base, where it meets the surface and where the violent activity originates. Nature provides brief glimpses during solar eclipses when the moon covers the bright surface of the sun allowing the dimmer corona to shine through, but continuous observations have been more difficult. Telescopes on the ground trying to study weather on the sun have been hampered by our own weather. Turbulence in our atmosphere blurs images through the same effect that makes stars twinkle at night. Now, however, new adaptive optics on the 1.6 metre Goode Solar Telescope in California has reduced the shimmering effect of our atmosphere by a factor of ten. This improvement allows us to see features at 63 kilometre resolution, which is closer than ever before. The trick was a flexible mirror that changes shape 2200 times per second, compensating and correcting for atmospheric distortion as it happens. This has resulted in the highest resolution images and movies ever made of the boundary between the surface of the sun and the corona. WATCH | What the clearest images of the sun's corona reveal: Clearest images yet of Sun's corona show city-sized blobs of plasma bouncing off the sun 4 hours ago Duration 0:31 The stunningly beautiful images reveal what looks like a fluffy surface on the sun with giant loops of material rising up, seemingly dancing and twisting with the sun's magnetic field. Meanwhile, cooler coronal raindrops, which can be narrower than 20 kilometres wide, fall back down. The observations also show something scientists have never seen before: a plasma stream they're calling a "plasmoid" moving across the solar surface at 100 kilometres per second. This is the region where solar flares and coronal mass ejections produce giant blobs of electrically charged material many times larger than the Earth, which blast off the sun and strike our planet's magnetic field. The result is beautiful northern and southern lights, but also a damaging effect on electronics in satellites and power surges in electrical grids causing blackouts. A dramatic example of this effect came in 1989 when a coronal mass ejection caused the Quebec power grid to shut down, casting most of the province into darkness for nine hours. Since then, power systems have been hardened against such events, but with more dependence on GPS satellites, navigation systems could still be interrupted. Even astronauts on the International Space Station need to seek shelter in their spacecraft to avoid the harmful radiation effects of solar flares. Future astronauts on the moon will be under similar threats from solar storms. Predicting violent solar events is challenging because the surface of the sun is a complicated, violent place that is ever changing, partly due to the fact that the equator of our star rotates faster than the poles. This causes turbulence in the hot gasses and twists the powerful magnet field into loops that can snap, releasing material into space. The sun also goes through cycles every 11 years where solar activity waxes and wanes. We are in a period of solar maximum at the moment, so monitoring its activity is important. These new corrective lenses, which can also be fitted to other solar telescopes, will enable scientists to dive into the mystery of why the corona is so hot and how solar disturbances originate. This could improve predictions in space weather so warnings can be issued earlier. As with weather on Earth, an accurate long-term weather forecast can be vital. Hopefully this will mean we see space weather coming more clearly.
The Guardian
16 hours ago
- Lifestyle
- The Guardian
‘Science is a human endeavor': astrophysicist uses art to connect Black and brown kids to the Stem fields
When practicing funeral ceremonies during the antebellum period, enslaved west Africans mimicked the sun's rotation as they danced counterclockwise in hidden clearings. They would sing and shuffle their feet to the beat of the drums in a ring shout, a ritual to honor the deceased that originated in Africa and which is still practiced by the descendants of enslaved people in the south-east US today. For the bereaved who grieved the recent death of a loved one, their practice orbited around the setting sun. So begins a chapter about our closest star in Painting the Cosmos, a recent book by UC Santa Cruz astrophysicist Dr Nia Imara. The book blends science and art in an ode to the diversity of the cosmos. While touching on astronomical tidbits, such as the fact that scientists measure the rate of the sun's spin by tracking the sunspots on its surface, Imara demonstrates the influence of astronomy on life and culture throughout history. She compares the sun's rhythmic cycle to the repetition found in the Black artist Alma Thomas's abstract paintings of space, and the patterns in the west African Bwa people's multicolored wooden masks depicting the sun and nature. As a painter and one of the only Black female astronomy professors in the US, Imara focuses on the contributions of Black and brown artists and scientists throughout her book. For Imara, it's important that young Black and brown people also see people in the sciences who look like them. That's why she created the non-profit Onaketa in 2020 to offer free science, technology, engineering and mathematics (Stem) online tutoring for Black and brown youth throughout the nation, who are mentored by scientists of color. 'Oftentimes when we're taught science and math in school, the focus in our textbooks and in the classrooms is on the contributions of white folks, and it's really important to show people that science is a human endeavor,' Imara said. 'Astronomy is often considered the oldest science, and certainly people from all over the world have made really valuable contributions.' Diversity is necessary for harmony in the universe, Imara argues in her book. Our solar system consists of eight planets of varying sizes, temperatures and features. 'If you change any one of these eight planets, or you didn't have one of them for some reason, that would have serious implications for the development of life on Earth,' Imara said. Jupiter, the largest planet in our solar system, has a large gravitational influence that deflects meteors that would otherwise hit the Earth's surface; and if Saturn were any smaller that it currently is, the Earth's orbit around the sun would change and might no longer hold liquid water. 'One of the things that science has taught me is that there are so many metaphors like this in nature,' Imara said. 'And if we take them to heart and apply them to ourselves here, I think that would really go a long way in how we treat each other, and how our society works.' Imara became interested in astronomy at a young age as she pondered existential questions about human life: 'What is the meaning of all this, and where do we fit into the universe?' As a sophomore in high school, she took a physics class that answered some of her fundamental questions. 'My relationship to science now has evolved so that I don't think any more that science can answer all of these big, deep questions, which are often very religious, very philosophical and even moral in nature,' Imara said. 'But I appreciate science and nature even more for the metaphors that it has to offer and also because of its ability to connect to people.' More than two decades ago, Imara began practicing visual art as a way to exercise another side of her brain and heart. Art, she said, has helped address some of her queries about human connectedness that science failed to answer. In her book, she writes that art and science haven't always been viewed as diametrically opposed. The Great Pyramid of Giza, in Egypt, which was built as a tomb for Pharaoh Khufu 4,500 years ago, merged science and art as the tallest building in the world until the 1800s. The monument displays precise geometry, and its shape nods to Benben, which was the first mound of land to be created according to ancient Egyptian religion. For Imara, the Great Pyramid is 'emblematic of how this incredible society brought together so many fields that we often treat as disparate. And it still blows my mind to think about the precision with which this monument was designed, conceived and constructed with all of the alignments with the cardinal directions, and the really precise alignment of air shafts within the pyramid to certain constellations and stars that were important to the Egyptians.' In pursuit of highlighting the achievements of Black and brown scientists outside her work as an astronomer and visual artist, Imara turned to education to create opportunities for marginalized youth. So she launched her organization Onaketa to offer personalized Stem tutoring to Black and brown youth. Middle and high schoolers are partnered up with Black and brown scientists who tutor them online on a weekly basis for up to a year. Over the past five years, six tutors have mentored more than 100 students throughout the country. 'Most of our students have never encountered a Black or brown scientist as a teacher or as a professor,' Imara said. 'To have somebody who is also a mentor who can guide them and show them new possibilities for themselves is really important.' Imara sees the program as a way to 'encourage Black and brown youth who have been actively discouraged and undermined from pursuing these fields. It's a matter of putting that attention, resources and love towards people who have been actively underserved.' Chima McGruder, an Onaketa mentor since 2021 who has a background in astrophysics, said that along with tutoring students in math through the program, he also serves as a role model for students who can see themselves in him. He's built up strong connections with some of the students whom he's mentored for several semesters. 'A lot of them don't get support that they would otherwise in math, or just someone who they can look up to who is not their parents,' McGruder said. 'I find those interactions very rewarding and it actually makes me feel like I'm making a difference.' McGruder said that it's important to expose Black and brown students to Stem fields at an early age since they are largely underrepresented in that sector. While Latinos compose 17% of the workforce across all jobs, they only represent 8% of people in Stem occupations, according to a 2021 Pew Research Center analysis of employment data. And Black workers make up 11% of the workforce and 9% of Stem workers. A diversity of perspective ensures that products and medicines are applicable to different populations, since some diseases have a correlation to race, McGruder said: 'Who you are and what your background is plays into the things that you create and the standards that you make.' Toward the end of the chapter about the sun's rhythm in her book, Imara reminds readers that everything they see is a reflection of the sun's light. And just as the star's own cycle waxes and wanes, so do the moments of our lives, Imara writes in the book: 'A government bent on war and defense will see a potential enemy in everything, including phenomena caused by the innocent sun. An enslaved people see in the same sun a powerful symbol that connects them with home, with their ancestors. It offers a perpetual reminder that life occurs in cycles – rhythms – and thus, their peculiar situation is not permanent.'
Malay Mail
17 hours ago
- General
- Malay Mail
Astronomers discover mysterious star emitting rare combination of X-rays and radio waves
WASHINGTON, May 31 — Astronomers have spotted a star acting unlike any other ever observed as it unleashes a curious combination of radio waves and X-rays, pegging it as an exotic member of a class of celestial objects first identified only three years ago. It is located in the Milky Way galaxy about 15,000 light-years from Earth in the direction of the constellation Scutum, flashing every 44 minutes in both radio waves and X-ray emissions. A light-year is the distance light travels in a year, 5.9 trillion miles (9.5 trillion km). The researchers said it belongs to a class of objects called 'long-period radio transients,' known for bright bursts of radio waves that appear every few minutes to several hours. This is much longer than the rapid pulses in radio waves typically detected from pulsars - a type of speedily rotating neutron star, the dense collapsed core of a massive star after its death. Pulsars appear, as viewed from Earth, to be blinking on and off on timescales of milliseconds to seconds. 'What these objects are and how they generate their unusual signals remain a mystery,' said astronomer Ziteng Wang of Curtin University in Australia, lead author of the study published this week in the journal Nature. In the new study, the researchers used data from Nasa's orbiting Chandra X-ray Observatory, the ASKAP telescope in Australia and other telescopes. While the emission of radio waves from the newly identified object is similar to the approximately 10 other known examples of this class, it is the only one sending out X-rays, according to astrophysicist and study co-author Nanda Rea of the Institute of Space Sciences in Barcelona. The researchers have some hypotheses about the nature of this star. They said it may be a magnetar, a spinning neutron star with an extreme magnetic field, or perhaps a white dwarf, a highly compact stellar ember, with a close and quick orbit around a small companion star in what is called a binary system. 'However, neither of them could explain all observational features we saw,' Wang said. Stars with up to eight times the mass of our sun appear destined to end up as a white dwarf. They eventually burn up all the hydrogen they use as fuel. Gravity then causes them to collapse and blow off their outer layers in a 'red giant' stage, eventually leaving behind a compact core roughly the diameter of Earth — the white dwarf. The observed radio waves potentially could have been generated by the interaction between the white dwarf and the hypothesized companion star, the researchers said. 'The radio brightness of the object varies a lot. We saw no radio emission from the object before November 2023. And in February 2024, we saw it became extremely bright. 'Fewer than 30 objects in the sky have ever reached such brightness in radio waves. Remarkably, at the same time, we also detected X-ray pulses from the object. We can still detect it in radio, but much fainter,' Wang said. Wang said it is thrilling to see a new type of behavior for stars. 'The X-ray detection came from NASA's Chandra space telescope. That part was a lucky break. The telescope was actually pointing at something else, but just happened to catch the source during its 'crazy' bright phase. A coincidence like that is really, really rare - like finding a needle in a haystack,' Wang said. — Reuters
ABC News
a day ago
- Climate
- ABC News
Crowds spill onto New York streets and block traffic to catch glimpse of 'Manhattanhenge' sunset
Crowds have spilled onto the streets of New York to catch a glimpse of a beloved phenomenon that bathes Manhattan streets in orange twice a year. "Manhattanhenge" occurs when the Sun perfectly aligns with the borough's street grid and sinks below the horizon, framed by a canyon of skyscrapers. Sidewalks and parks were packed to watch the unique sunset on Thursday, local time, which occurs on a handful of spring and summer evenings. The first Manhattanhenge of the year took place on Wednesday evening, but was repeated again on Thursday. Thursday's sunset was briefly visible, but mostly blocked by clouds. It will occur again on July 11 and 12. Astrophysicist Neil deGrasse Tyson coined the term in an article published in the National History magazine in 1997. The future television host was part of an expedition led by Gerald Hawkins, the scientist who first theorised that Stonehenge was constructed as an ancient astronomical observatory. It struck Dr Tyson, who is a New York local, that the biannual sunset alignment that occurs in Manhattan could be compared to the Sun's rays striking the centre of the Stonehenge circle on the summer solstice. The summer solstice is an annual event that refers to when a hemisphere experiences its longest stretch of daylight over a 24-hour period. Manhattanhenge doesn't take place on the summer solstice itself, though. The two events are separated by about three weeks before and after the solstice. AP
Reuters
2 days ago
- General
- Reuters
Astronomers scrutinize a star behaving unlike any other
WASHINGTON, May 29 (Reuters) - Astronomers have spotted a star acting unlike any other ever observed as it unleashes a curious combination of radio waves and X-rays, pegging it as an exotic member of a class of celestial objects first identified only three years ago. It is located in the Milky Way galaxy about 15,000 light-years from Earth in the direction of the constellation Scutum, flashing every 44 minutes in both radio waves and X-ray emissions. A light-year is the distance light travels in a year, 5.9 trillion miles (9.5 trillion km). The researchers said it belongs to a class of objects called "long-period radio transients," known for bright bursts of radio waves that appear every few minutes to several hours. This is much longer than the rapid pulses in radio waves typically detected from pulsars - a type of speedily rotating neutron star, the dense collapsed core of a massive star after its death. Pulsars appear, as viewed from Earth, to be blinking on and off on timescales of milliseconds to seconds. "What these objects are and how they generate their unusual signals remain a mystery," said astronomer Ziteng Wang of Curtin University in Australia, lead author of the study published this week in the journal Nature, opens new tab. In the new study, the researchers used data from NASA's orbiting Chandra X-ray Observatory, the ASKAP telescope in Australia and other telescopes. While the emission of radio waves from the newly identified object is similar to the approximately 10 other known examples of this class, it is the only one sending out X-rays, according to astrophysicist and study co-author Nanda Rea of the Institute of Space Sciences in Barcelona. The researchers have some hypotheses about the nature of this star. They said it may be a magnetar, a spinning neutron star with an extreme magnetic field, or perhaps a white dwarf, a highly compact stellar ember, with a close and quick orbit around a small companion star in what is called a binary system. "However, neither of them could explain all observational features we saw," Wang said. Stars with up to eight times the mass of our sun appear destined to end up as a white dwarf. They eventually burn up all the hydrogen they use as fuel. Gravity then causes them to collapse and blow off their outer layers in a "red giant" stage, eventually leaving behind a compact core roughly the diameter of Earth - the white dwarf. The observed radio waves potentially could have been generated by the interaction between the white dwarf and the hypothesized companion star, the researchers said. "The radio brightness of the object varies a lot. We saw no radio emission from the object before November 2023. And in February 2024, we saw it became extremely bright. Fewer than 30 objects in the sky have ever reached such brightness in radio waves. Remarkably, at the same time, we also detected X-ray pulses from the object. We can still detect it in radio, but much fainter," Wang said. Wang said it is thrilling to see a new type of behavior for stars. "The X-ray detection came from NASA's Chandra space telescope. That part was a lucky break. The telescope was actually pointing at something else, but just happened to catch the source during its 'crazy' bright phase. A coincidence like that is really, really rare - like finding a needle in a haystack," Wang said.
