How a planet survived the death of its sunlike star

Artist’s concept of the exoplanet WD 1856 b. It’s a gas giant, similar to Jupiter. A new study said the planet survived the death of its sunlike star billions of years ago. Now the planet orbits the remains of the star, a white dwarf, 50 times closer than Earth orbits the sun. Image via NASA/ ESA/ CSA/ Ralf Crawford (STScI).

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• A Jupiter-like exoplanet survived the death of its sunlike star, and now orbits the star’s white dwarf remnant 50 times closer than Earth orbits the sun.
• The planet shouldn’t have survived: when its star expanded into a red giant, anything this close should have been destroyed.
• New James Webb Space Telescope data reveal the planet actually migrated into its close orbit after the star died, and was heated by the white dwarf’s gravity along the way.

A survivor 50 times closer to its star than Earth

On July 1, 2026, NASA said the James Webb Space Telescope investigated a gas giant planet that not only survived the death of its sunlike star, but is also 50 times closer to its star than Earth is to the sun.

The planet in question (or exoplanet, as we call it when it orbits a star other than the sun) is named WD 1856 b, and it’s orbiting a white dwarf star. When the star was a red giant, it should have destroyed any nearby planet. But this gas giant exoplanet still orbits its star once every 34 hours from less than 2 million miles (3 million km or 0.02 astronomical units) away.

Someday, several billion years from now, our sun will expand into the last phase of its life when it becomes a red giant. When it does, it will engulf most of the inner planets in its swollen atmosphere. Eventually, all that will be left of the sun is its dense core: a white dwarf star. Will Earth survive? That’s still a matter of debate.

The researchers published their peer-reviewed study in the journal Nature on July 1, 2026.

How Webb investigated the surviving planet

To find out how a planet so close to its star could have survived the star’s red giant phase, a team of astronomers turned Webb on it. From the telescope’s point of view, the planet passes right in front of the star in what’s called a transit. During a transit, astronomers can get a look at the planet’s atmosphere. The team analyzed the atmosphere’s composition and measured its temperature.

Even though its star is now a slowly cooling white dwarf, the planet itself was warmer than astronomers expected. They determined its atmosphere was a toasty 260 degrees Fahrenheit (126 C). That’s hotter than it would be if the star were the sole source of heat.

The team also managed to discern a bit of the planetary atmosphere’s chemical composition. Co-author Victoria Boehm of Cornell University said:

We saw the telltale signatures of small cloud particles and hydrocarbons, most likely methane, which is the first time we have seen an atmosphere on a planet transiting a dead star.

NASA’s Transiting Exoplanet Survey Satellite (TESS) originally discovered the planet orbiting the star in 2020. The pair are 80 light-years away. Interestingly, now that the star is in its white dwarf phase, the planet is much larger than the star. Lead author Ryan MacDonald of the University of St. Andrews in the U.K. said:

The planet is about the size of Jupiter, but the white dwarf it orbits is the size of Earth, so the planet is 7 times larger than its star.

How did this close planet survive?

The planet is simply too close to its star to have survived there during the red giant phase. So astronomers reasoned that it migrated into that position sometime after the red giant phase ended. Looking closer at the temperature of the planet helped them crack the case.

The white dwarf doesn’t provide enough heat to account for the temperature of the planet, so there must be internal heat from an earlier time. Co-author Christopher O’Connor of Northwestern University modeled the heat of the planet backward to determine how long it took it to cool down. This would help astronomers know how long ago the planet acquired its heat. What they really wanted to know is whether the planet heated up due to the red giant phase of its star or as a consequence of its journey closer to the star.

And the calculations showed the planet heated up between 3 and 5.5 billion years after the star became a white dwarf, which couldn’t have resulted from the red giant phase. Originally, the scientists said, the planet was far enough away from the star in its orbit that it didn’t heat up as the stellar atmosphere swelled. But, O’Connor said:

As the planet moved inward, its interactions with the strong gravity of the white dwarf will have caused it to warm up considerably, and it has been cooling ever since.

The James Webb Space Telescope was able to detect molecules in the exoplanet WD 1856 b’s atmosphere as it passed in front of, or transited, its star. Its star is a white dwarf, and only about the size of Earth. So when the planet passes in front of the star, it blocks more than half the star’s light. The red bars show the methane Webb detected. Image via NASA/ ESA/ CSA/ Joseph Olmsted (STScI).

What’s next for the surviving planet?

The exoplanet WD 1856 b will continue to slowly cool over the next few billion years. If there were any form of life on the planet, there’s no telling how it fared during the planet’s wild ride inward toward its star: first heating up as gravity took hold, then slowly cooling ever since.

Perhaps the future of Jupiter or one of the other gas giant planets in our solar system will resemble that of WD 1856 b. MacDonald said:

We’re used to looking back in time when we use telescopes, but this is the first time we have been able to look forward to what might happen to the outer planets around the remnant of a sunlike star. It’s like using a time machine to peer into the distant future of our solar system.

Bottom line: A Jupiter-like exoplanet survived the death of its sunlike star and now orbits the star’s white dwarf remnant 50 times closer than Earth orbits the sun. New Webb data show the planet migrated inward after the star’s death, rather than surviving its scorching red giant phase in place.

Source: Aerosols and hydrocarbons in the atmosphere of a white dwarf planet

Via NASA

The post How a planet survived the death of its sunlike star first appeared on EarthSky.

from EarthSky https://ift.tt/whCWfRd

Artist’s concept of the exoplanet WD 1856 b. It’s a gas giant, similar to Jupiter. A new study said the planet survived the death of its sunlike star billions of years ago. Now the planet orbits the remains of the star, a white dwarf, 50 times closer than Earth orbits the sun. Image via NASA/ ESA/ CSA/ Ralf Crawford (STScI).

EarthSky isn’t powered by billionaires. We’re powered by you. Support EarthSky’s 2026 Donation Campaign and help keep science accessible.

• A Jupiter-like exoplanet survived the death of its sunlike star, and now orbits the star’s white dwarf remnant 50 times closer than Earth orbits the sun.
• The planet shouldn’t have survived: when its star expanded into a red giant, anything this close should have been destroyed.
• New James Webb Space Telescope data reveal the planet actually migrated into its close orbit after the star died, and was heated by the white dwarf’s gravity along the way.

A survivor 50 times closer to its star than Earth

On July 1, 2026, NASA said the James Webb Space Telescope investigated a gas giant planet that not only survived the death of its sunlike star, but is also 50 times closer to its star than Earth is to the sun.

The planet in question (or exoplanet, as we call it when it orbits a star other than the sun) is named WD 1856 b, and it’s orbiting a white dwarf star. When the star was a red giant, it should have destroyed any nearby planet. But this gas giant exoplanet still orbits its star once every 34 hours from less than 2 million miles (3 million km or 0.02 astronomical units) away.

Someday, several billion years from now, our sun will expand into the last phase of its life when it becomes a red giant. When it does, it will engulf most of the inner planets in its swollen atmosphere. Eventually, all that will be left of the sun is its dense core: a white dwarf star. Will Earth survive? That’s still a matter of debate.

The researchers published their peer-reviewed study in the journal Nature on July 1, 2026.

How Webb investigated the surviving planet

To find out how a planet so close to its star could have survived the star’s red giant phase, a team of astronomers turned Webb on it. From the telescope’s point of view, the planet passes right in front of the star in what’s called a transit. During a transit, astronomers can get a look at the planet’s atmosphere. The team analyzed the atmosphere’s composition and measured its temperature.

Even though its star is now a slowly cooling white dwarf, the planet itself was warmer than astronomers expected. They determined its atmosphere was a toasty 260 degrees Fahrenheit (126 C). That’s hotter than it would be if the star were the sole source of heat.

The team also managed to discern a bit of the planetary atmosphere’s chemical composition. Co-author Victoria Boehm of Cornell University said:

We saw the telltale signatures of small cloud particles and hydrocarbons, most likely methane, which is the first time we have seen an atmosphere on a planet transiting a dead star.

NASA’s Transiting Exoplanet Survey Satellite (TESS) originally discovered the planet orbiting the star in 2020. The pair are 80 light-years away. Interestingly, now that the star is in its white dwarf phase, the planet is much larger than the star. Lead author Ryan MacDonald of the University of St. Andrews in the U.K. said:

The planet is about the size of Jupiter, but the white dwarf it orbits is the size of Earth, so the planet is 7 times larger than its star.

How did this close planet survive?

The planet is simply too close to its star to have survived there during the red giant phase. So astronomers reasoned that it migrated into that position sometime after the red giant phase ended. Looking closer at the temperature of the planet helped them crack the case.

The white dwarf doesn’t provide enough heat to account for the temperature of the planet, so there must be internal heat from an earlier time. Co-author Christopher O’Connor of Northwestern University modeled the heat of the planet backward to determine how long it took it to cool down. This would help astronomers know how long ago the planet acquired its heat. What they really wanted to know is whether the planet heated up due to the red giant phase of its star or as a consequence of its journey closer to the star.

And the calculations showed the planet heated up between 3 and 5.5 billion years after the star became a white dwarf, which couldn’t have resulted from the red giant phase. Originally, the scientists said, the planet was far enough away from the star in its orbit that it didn’t heat up as the stellar atmosphere swelled. But, O’Connor said:

As the planet moved inward, its interactions with the strong gravity of the white dwarf will have caused it to warm up considerably, and it has been cooling ever since.

The James Webb Space Telescope was able to detect molecules in the exoplanet WD 1856 b’s atmosphere as it passed in front of, or transited, its star. Its star is a white dwarf, and only about the size of Earth. So when the planet passes in front of the star, it blocks more than half the star’s light. The red bars show the methane Webb detected. Image via NASA/ ESA/ CSA/ Joseph Olmsted (STScI).

What’s next for the surviving planet?

The exoplanet WD 1856 b will continue to slowly cool over the next few billion years. If there were any form of life on the planet, there’s no telling how it fared during the planet’s wild ride inward toward its star: first heating up as gravity took hold, then slowly cooling ever since.

Perhaps the future of Jupiter or one of the other gas giant planets in our solar system will resemble that of WD 1856 b. MacDonald said:

We’re used to looking back in time when we use telescopes, but this is the first time we have been able to look forward to what might happen to the outer planets around the remnant of a sunlike star. It’s like using a time machine to peer into the distant future of our solar system.

Bottom line: A Jupiter-like exoplanet survived the death of its sunlike star and now orbits the star’s white dwarf remnant 50 times closer than Earth orbits the sun. New Webb data show the planet migrated inward after the star’s death, rather than surviving its scorching red giant phase in place.

Source: Aerosols and hydrocarbons in the atmosphere of a white dwarf planet

Via NASA

The post How a planet survived the death of its sunlike star first appeared on EarthSky.

from EarthSky https://ift.tt/whCWfRd

Happy 90th birthday to Guy Ottewell, chart-maker of the night sky

Guy Ottewell is a poet and artist, as well as a master astronomy chart-maker. Here’s one of his illustrations. It shows the asterism – or noticeable star pattern – known as the Northern Cross in the night sky. Image via Guy Ottewell. Used with permission.

The man behind the yearly Astronomical Calendar

Beloved British astronomer Guy Ottewell turns 90 on July 4, 2026. EarthSky wishes him a warm congrats on completing another trip around the sun. Guy Ottewell is best known worldwide for his beautiful astronomy charts and hand-illustrated yearly Astronomical Calendar, of which 2026 will be the final year. Virtually every astronomy educator knows Guy’s calendar and employs it in teaching about the night sky and outer space. Millions have benefited from Ottewell’s unique view of outer space.

Ottewell’s Astronomical Calendar was popular as a printed book from 1974 to 2016. Thousands of sky-lovers in more than 100 countries purchased it. It took a hiatus beginning in 2017, but returned in 2023, in both printed and electronic formats. 2026 is the final year of Guy Ottewell’s Astronomical Calendar.

And if you’re a regular reader of EarthSky, you’ll have seen many of his charts in our sky guide and more over the years.

View Guy’s publications page. Many of his publications are still available for sale, either here or on sites such as eBay.

2026 chart showing the evening apparition of the brightest planet, Venus, by Guy Ottewell. This chart shows Venus from the Southern Hemisphere; the Northern Hemisphere path is similar, but the planet doesn’t get as high in the sky. Planet images are at the 1st, 11th, and 21st of each month. The changing phase of Venus requires a telescope to see. Chart via Guy Ottewell’s 2026 Astronomical Calendar. Used with permission.

Guy Ottewell: A well-traveled educator

Guy Ottewell spent his childhood in Warwickshire, in the UK’s West Midlands, and his adolescence in Surrey, southeast of London. He did army service in Libya and hitchhiked home from there via Greece, Yugoslavia, Venice, Holland. He said:

I had done well enough at school in Greek and Latin to earn a scholarship to Cambridge, but, while there, studied Arabic, Persian, archaeology and anthropology. On vacations, I made hitchhiking journeys to Switzerland (to work in a theater), Morocco, and Iran and Afghanistan (returning from there via central Asia and Finland).

My first extended job was at a school in Arab Jerusalem, living there with my late wife Barbara. At Manchester University, and then at UCLA, I cataloged their libraries’ books in Middle Eastern languages. While at Manchester, I was encouraged to make a study of modern Hebrew, and traveled around Israel, once living in a kibbutz. For two years, I was a teacher at a native American “demonstration” school in the Navajo reservation in Arizona. Open-air camping during my travels had inspired me to know the stars, but it was at the Navajo school that I first had use of a telescope. And I collected Navajo star lore.

Then my wife was asked to start a Montessori school at Greenville, South Carolina, so we moved. Being ready to turn from astronomy to another side of nature – plants – I grew 80 kinds of vegetables and made botanical drawings.

But I was asked by Professor Bill Brantley, of the Physics Department at Furman University, to show the stars to students. This led to his suggestion of an astronomical yearbook that the Physics department could publish. This later became the yearly Astronomical Calendar. It turned out to meet a need, and I had to teach myself trigonometry and computer programming.

The early publishing imprint Astronomical Workshop – under which the Calendar and other works were initially released – had to become Universal Workshop when I took to the printer a book about human rights. I then added publications in some of my other fields of interest – history, fiction, poetry. Though not an employee of the university, I had the use of storage space and an office for fulfilling orders.

In 2001, I moved to England with my wife, Tilly, a journalist, and continued to publish the Astronomical Calendar.

My more recent journeys have been to see solar eclipses in Canada, Kenya, Java, Mexico, West Texas, India, Mongolia, the Caribbean, Turkey, Australia; to Peru at the time of Halley’s Comet; and long cycle rides in Italy, Turkey, Greece and India.

Guy’s artistic talents extend beyond his scientific illustrations, as demonstrated by this self-portrait.

Self-portrait by Guy Ottewell. Over the course of his lifetime, he has been an inveterate hiker and bike rider. Find his tips for traveling with your bicycle here.

View Guy Ottewell’s blog posts and charts at EarthSky

Ottewell routinely blogs at his website, Universal Workshop. And, in recent years, many of his blog posts have been reprinted at EarthSky.org.

At least through the end of 2026, you can also find his charts at EarthSky’s most popular post, our visible planet and night sky guide. EarthSky founder Deborah Byrd described Guy’s contributions to astronomy this way:

Through his own efforts, unaffiliated with any large organization, Guy has conveyed astronomy to millions of people since 1974. That’s when he published the original edition of his yearly Astronomical Calendar. He has published it since then, and it has become one of the most beloved resources in astronomy.

2026 chart showing the path of Comet Encke relative to the ecliptic plane (Earth-sun plane). Comets’ paths are drawn as thicker when brighter. Ticks mark the start of days 1, 11 and 21 of each month. Chart via Guy Ottewell’s 2026 Astronomical Calendar. Used with permission.

A view of Earth from space showing the timing and path of the total solar eclipse on August 12, 2026. Chart via Guy Ottewell’s 2026 Astronomical Calendar. Used with permission.

A sample of Guy Ottewell’s star charts. This one shows stars within 12 light-years of our sun. The lines on the grid are 4 light-years apart. Imaginary stalks from the plane to the stars show how far north or south they are. Proxima Centauri is part of the triple star system we see as the single star Alpha Centauri. Image via Guy Ottewell. Used with permission.

A voice that inspired generations of skywatchers

EarthSky’s John Jardine Goss, who is also a former president of the Astronomical League, shared his insight on Guy:

All his works – which include a number of topical, in-depth books and beautiful wall posters – have inspired curious skywatchers and amateur astronomers to see more, and to learn more while they pursue the fascinating field of astronomy.

The late Alan Hale, co-discoverer of Comet Hale-Bopp, said this about Ottewell:

In addition to his astronomical writings and publications, Guy Ottewell has also engaged in numerous humanitarian efforts, and these infuse his writings. In so doing he is not only providing informational and educational benefits to his readers but is also demonstrating that the solar system and the universe within which we live are part of the common heritage of humanity.

And Joe Patterson, professor of astronomy at Columbia University, summed up our feelings at EarthSky when he said:

There’s nobody in Ottewell’s class.

Bottom line: Longtime astronomy educator Guy Ottewell turns 90 on July 4, 2026. Guy is best known for his beautiful astronomy charts and hand-illustrated yearly Astronomical Calendar.

The post Happy 90th birthday to Guy Ottewell, chart-maker of the night sky first appeared on EarthSky.

from EarthSky https://ift.tt/uGvNh5c

Guy Ottewell is a poet and artist, as well as a master astronomy chart-maker. Here’s one of his illustrations. It shows the asterism – or noticeable star pattern – known as the Northern Cross in the night sky. Image via Guy Ottewell. Used with permission.

The man behind the yearly Astronomical Calendar

Beloved British astronomer Guy Ottewell turns 90 on July 4, 2026. EarthSky wishes him a warm congrats on completing another trip around the sun. Guy Ottewell is best known worldwide for his beautiful astronomy charts and hand-illustrated yearly Astronomical Calendar, of which 2026 will be the final year. Virtually every astronomy educator knows Guy’s calendar and employs it in teaching about the night sky and outer space. Millions have benefited from Ottewell’s unique view of outer space.

Ottewell’s Astronomical Calendar was popular as a printed book from 1974 to 2016. Thousands of sky-lovers in more than 100 countries purchased it. It took a hiatus beginning in 2017, but returned in 2023, in both printed and electronic formats. 2026 is the final year of Guy Ottewell’s Astronomical Calendar.

And if you’re a regular reader of EarthSky, you’ll have seen many of his charts in our sky guide and more over the years.

View Guy’s publications page. Many of his publications are still available for sale, either here or on sites such as eBay.

2026 chart showing the evening apparition of the brightest planet, Venus, by Guy Ottewell. This chart shows Venus from the Southern Hemisphere; the Northern Hemisphere path is similar, but the planet doesn’t get as high in the sky. Planet images are at the 1st, 11th, and 21st of each month. The changing phase of Venus requires a telescope to see. Chart via Guy Ottewell’s 2026 Astronomical Calendar. Used with permission.

Guy Ottewell: A well-traveled educator

Guy Ottewell spent his childhood in Warwickshire, in the UK’s West Midlands, and his adolescence in Surrey, southeast of London. He did army service in Libya and hitchhiked home from there via Greece, Yugoslavia, Venice, Holland. He said:

I had done well enough at school in Greek and Latin to earn a scholarship to Cambridge, but, while there, studied Arabic, Persian, archaeology and anthropology. On vacations, I made hitchhiking journeys to Switzerland (to work in a theater), Morocco, and Iran and Afghanistan (returning from there via central Asia and Finland).

My first extended job was at a school in Arab Jerusalem, living there with my late wife Barbara. At Manchester University, and then at UCLA, I cataloged their libraries’ books in Middle Eastern languages. While at Manchester, I was encouraged to make a study of modern Hebrew, and traveled around Israel, once living in a kibbutz. For two years, I was a teacher at a native American “demonstration” school in the Navajo reservation in Arizona. Open-air camping during my travels had inspired me to know the stars, but it was at the Navajo school that I first had use of a telescope. And I collected Navajo star lore.

Then my wife was asked to start a Montessori school at Greenville, South Carolina, so we moved. Being ready to turn from astronomy to another side of nature – plants – I grew 80 kinds of vegetables and made botanical drawings.

But I was asked by Professor Bill Brantley, of the Physics Department at Furman University, to show the stars to students. This led to his suggestion of an astronomical yearbook that the Physics department could publish. This later became the yearly Astronomical Calendar. It turned out to meet a need, and I had to teach myself trigonometry and computer programming.

The early publishing imprint Astronomical Workshop – under which the Calendar and other works were initially released – had to become Universal Workshop when I took to the printer a book about human rights. I then added publications in some of my other fields of interest – history, fiction, poetry. Though not an employee of the university, I had the use of storage space and an office for fulfilling orders.

In 2001, I moved to England with my wife, Tilly, a journalist, and continued to publish the Astronomical Calendar.

My more recent journeys have been to see solar eclipses in Canada, Kenya, Java, Mexico, West Texas, India, Mongolia, the Caribbean, Turkey, Australia; to Peru at the time of Halley’s Comet; and long cycle rides in Italy, Turkey, Greece and India.

Guy’s artistic talents extend beyond his scientific illustrations, as demonstrated by this self-portrait.

Self-portrait by Guy Ottewell. Over the course of his lifetime, he has been an inveterate hiker and bike rider. Find his tips for traveling with your bicycle here.

View Guy Ottewell’s blog posts and charts at EarthSky

Ottewell routinely blogs at his website, Universal Workshop. And, in recent years, many of his blog posts have been reprinted at EarthSky.org.

At least through the end of 2026, you can also find his charts at EarthSky’s most popular post, our visible planet and night sky guide. EarthSky founder Deborah Byrd described Guy’s contributions to astronomy this way:

Through his own efforts, unaffiliated with any large organization, Guy has conveyed astronomy to millions of people since 1974. That’s when he published the original edition of his yearly Astronomical Calendar. He has published it since then, and it has become one of the most beloved resources in astronomy.

2026 chart showing the path of Comet Encke relative to the ecliptic plane (Earth-sun plane). Comets’ paths are drawn as thicker when brighter. Ticks mark the start of days 1, 11 and 21 of each month. Chart via Guy Ottewell’s 2026 Astronomical Calendar. Used with permission.

A view of Earth from space showing the timing and path of the total solar eclipse on August 12, 2026. Chart via Guy Ottewell’s 2026 Astronomical Calendar. Used with permission.

A sample of Guy Ottewell’s star charts. This one shows stars within 12 light-years of our sun. The lines on the grid are 4 light-years apart. Imaginary stalks from the plane to the stars show how far north or south they are. Proxima Centauri is part of the triple star system we see as the single star Alpha Centauri. Image via Guy Ottewell. Used with permission.

A voice that inspired generations of skywatchers

EarthSky’s John Jardine Goss, who is also a former president of the Astronomical League, shared his insight on Guy:

All his works – which include a number of topical, in-depth books and beautiful wall posters – have inspired curious skywatchers and amateur astronomers to see more, and to learn more while they pursue the fascinating field of astronomy.

The late Alan Hale, co-discoverer of Comet Hale-Bopp, said this about Ottewell:

In addition to his astronomical writings and publications, Guy Ottewell has also engaged in numerous humanitarian efforts, and these infuse his writings. In so doing he is not only providing informational and educational benefits to his readers but is also demonstrating that the solar system and the universe within which we live are part of the common heritage of humanity.

And Joe Patterson, professor of astronomy at Columbia University, summed up our feelings at EarthSky when he said:

There’s nobody in Ottewell’s class.

Bottom line: Longtime astronomy educator Guy Ottewell turns 90 on July 4, 2026. Guy is best known for his beautiful astronomy charts and hand-illustrated yearly Astronomical Calendar.

The post Happy 90th birthday to Guy Ottewell, chart-maker of the night sky first appeared on EarthSky.

from EarthSky https://ift.tt/uGvNh5c

How do fireworks get their beautiful colors?

View at EarthSky Community Photos. | C. Gentile from Florham Park, New Jersey, captured this image of a July 4th celebration and wrote: “The sky was really this color!” Thank you! And happy 4th of July to all who celebrate it. Read what creates the beautiful colors in fireworks below.

Science matters. Wonder matters. You matter. Join our 2026 Donation Campaign today.

The U.S. has a big holiday tomorrow. It’s the 250th Independence Day, aka the 4th of July. And that means it’s fireworks season!

If you watch your local fireworks display, you’ll see the reds, oranges, yellows, greens, blues and purples exploding in the skies. You’ll hear lots of “oohs” and “ahs!”

But what creates the colors of fireworks?

How to sound really smart to your friends on the 4th of July: Know what minerals create the colors in fireworks. ? ? #knowbefore pic.twitter.com/vqnr9617TO

— WeatherBug (@WeatherBug) July 1, 2024

What creates the colors in fireworks?

The colors in fireworks come from a simple source. They’re created by the use of metal salts. These chemical salts are different from table salt, referring instead to any compound that contains metal and non-metal atoms. And some of these compounds produce intense colors when they burn, which makes them ideal for fireworks.

Others, like potassium nitrate, sulfur and charcoal are useful to help the fireworks burn. Nitrates, chlorates and perchlorates provide oxygen for the combustion of the fuel. Dextrin, often used as a starch, holds the mixture together. In addition, the use of chlorine-carrying chemicals strengthens some colors.

Metal salts commonly used in firework displays include: strontium carbonate (red fireworks), calcium chloride (orange fireworks), sodium nitrate (yellow fireworks), barium chloride (green fireworks) and copper chloride (blue fireworks). Purple fireworks are typically a mixture of strontium (red) and copper (blue) compounds.

Then they pack these metal salts into small pea- to plum-sized pellets called “stars” or pyrotechnic stars.

View at EarthSky Community Photos. | Ken Chan captured this image at the 4th of July celebration in San Francisco, California, in 2023. He wrote: “July 4th as celebratory fireworks erupted throughout the city.” Thank you, Ken!

What happens after fireworks ignite?

After a firework ignites, a lift charge propels it into the sky. That’s just explosive black powder in a confined space that, when lit, causes a fast increase of heat and gas that can send a firework as high as 1,000 feet (300 meters) into the air.

Meanwhile, a time-delay fuse burns slowly into the interior of the firework shell. Then, after about five seconds, as the shell is soaring overhead, the fuse kindles a charge that reaches the core of the firework, explodes and ignites the stars that contain the metal salts.

Voilà! A beautiful and colorful fireworks display.

Word of caution

By the way, the people who create fireworks are precise, expert craftsmen. If even one thing is off – too much black powder, stars that aren’t aligned correctly or a trigger that fires too soon or too late – everything can go kaboom. After all, fireworks are explosives, and working with them is best left to the professionals.

Bottom line: The red, orange, yellow, green, blue and purple colors exploding in the night sky during a fireworks festival are created by the use of metal salts.

Read more: The Chemistry of Fireworks Colors

Read more: The Chemistry of Fireworks

Enjoying EarthSky? Sign up for our free daily newsletter today!

The post How do fireworks get their beautiful colors? first appeared on EarthSky.

from EarthSky https://ift.tt/OAfcnB2

View at EarthSky Community Photos. | C. Gentile from Florham Park, New Jersey, captured this image of a July 4th celebration and wrote: “The sky was really this color!” Thank you! And happy 4th of July to all who celebrate it. Read what creates the beautiful colors in fireworks below.

Science matters. Wonder matters. You matter. Join our 2026 Donation Campaign today.

The U.S. has a big holiday tomorrow. It’s the 250th Independence Day, aka the 4th of July. And that means it’s fireworks season!

If you watch your local fireworks display, you’ll see the reds, oranges, yellows, greens, blues and purples exploding in the skies. You’ll hear lots of “oohs” and “ahs!”

But what creates the colors of fireworks?

How to sound really smart to your friends on the 4th of July: Know what minerals create the colors in fireworks. ? ? #knowbefore pic.twitter.com/vqnr9617TO

— WeatherBug (@WeatherBug) July 1, 2024

What creates the colors in fireworks?

The colors in fireworks come from a simple source. They’re created by the use of metal salts. These chemical salts are different from table salt, referring instead to any compound that contains metal and non-metal atoms. And some of these compounds produce intense colors when they burn, which makes them ideal for fireworks.

Others, like potassium nitrate, sulfur and charcoal are useful to help the fireworks burn. Nitrates, chlorates and perchlorates provide oxygen for the combustion of the fuel. Dextrin, often used as a starch, holds the mixture together. In addition, the use of chlorine-carrying chemicals strengthens some colors.

Metal salts commonly used in firework displays include: strontium carbonate (red fireworks), calcium chloride (orange fireworks), sodium nitrate (yellow fireworks), barium chloride (green fireworks) and copper chloride (blue fireworks). Purple fireworks are typically a mixture of strontium (red) and copper (blue) compounds.

Then they pack these metal salts into small pea- to plum-sized pellets called “stars” or pyrotechnic stars.

View at EarthSky Community Photos. | Ken Chan captured this image at the 4th of July celebration in San Francisco, California, in 2023. He wrote: “July 4th as celebratory fireworks erupted throughout the city.” Thank you, Ken!

What happens after fireworks ignite?

After a firework ignites, a lift charge propels it into the sky. That’s just explosive black powder in a confined space that, when lit, causes a fast increase of heat and gas that can send a firework as high as 1,000 feet (300 meters) into the air.

Meanwhile, a time-delay fuse burns slowly into the interior of the firework shell. Then, after about five seconds, as the shell is soaring overhead, the fuse kindles a charge that reaches the core of the firework, explodes and ignites the stars that contain the metal salts.

Voilà! A beautiful and colorful fireworks display.

Word of caution

By the way, the people who create fireworks are precise, expert craftsmen. If even one thing is off – too much black powder, stars that aren’t aligned correctly or a trigger that fires too soon or too late – everything can go kaboom. After all, fireworks are explosives, and working with them is best left to the professionals.

Bottom line: The red, orange, yellow, green, blue and purple colors exploding in the night sky during a fireworks festival are created by the use of metal salts.

Read more: The Chemistry of Fireworks Colors

Read more: The Chemistry of Fireworks

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Top 10 cool things about stars that you probably didn’t know

Here we present 10 cool things about stars!

We live in uncertain times. But things are always so much more peaceful, looking up. Please help EarthSky keep going!

1. Every star you see in the night sky is bigger and brighter than our sun

Of the 5,000 or so stars bright enough to see with the unaided eye (brighter than magnitude 6) only a handful of very faint stars are near the same size and brightness of our sun. All the rest are all bigger and brighter.

Of the 500 or so that are brighter than 4th magnitude – which includes essentially every star visible to the unaided eye from an urban location – all are bigger and brighter than our sun, many by a large percentage.

Of the brightest 50 stars visible to the human eye from Earth, the least intrinsically bright star is Alpha Centauri. This star still appears very bright to us, because it’s the closest star system to Earth at 4.2 light-years away. And Alpha Centauri is still more than 1.5 times more luminous than our sun.

Read about brightness and luminosity here

2. You can’t see millions of stars on a dark night

Despite what you may hear in poems, songs and commercials, you cannot see a million stars … anywhere. There simply are not enough stars close enough and bright enough to equal a million.

On a really exceptional night, with no moon and far from any source of lights, a person with very good eyesight may be able to see 2,000-2,500 stars at any one time. So the next time you hear someone claim to have seen a million stars in the sky, just attribute it to wonder-inspired exaggeration.

3. Red hot, blue cool? No!

We are accustomed to referring to things that are red as hot and those that are blue as cool. This is not entirely unreasonable, since a red, glowing fireplace poker is hot; and ice, especially in glaciers and polar regions, can have a bluish cast. But we say that only because our everyday experience is limited.

In fact, heated objects change color as their temperature changes. And red represents the lowest temperature at which a heated object can glow in visible light. As it gets hotter, the color changes to white and ultimately to blue. So the red stars you see in the sky are the “coolest” (least hot), and the blue stars are the hottest!

4. Stars are black bodies

A black body is an object that absorbs 100% of all electromagnetic radiation (light, radio waves and so on) that falls on it. A common image here is that of a brick oven with the interior painted black and the only opening a small window. All light that shines through the window is absorbed by the interior of the oven and none is reflected outside the oven. It is a perfect absorber.

As it turns out, this definition of being a perfect absorber suits stars very well! But this just says that a black body absorbs all the radiant energy that hits it. And it does not forbid the black body from re-emitting the energy. In the case of a star, it absorbs all radiation that falls on it, but it also radiates back into space much more than it absorbs. Thus a star is a black body that glows with great brilliance!

An even more perfect black body is a black hole. But, unlike stars, a black hole appears truly black, and radiates no light.

5. There are no green stars

There are scattered claims for stars that appear green, including Beta Librae (Zubeneschamali). But most observers do not see green in any stars except as an optical effect from their telescopes, or else a quirk of personal vision and contrast.

Stars emit a spectrum (“rainbow”) of colors, including green. But the human eye-brain connection mixes the colors together in a manner that rarely, if ever, comes out green. One color can dominate the radiation, but within the range of wavelengths and intensities found in stars, greens get mixed with other colors. And in that case the star appears white. For stars, the general colors are, from lower to higher temperatures, red, orange, yellow, white and blue. So as far as the human eye can tell, there are no green stars.

The sun in extreme ultraviolet, converted to the false color green. The human eye cannot see ultraviolet at all. Keep reading for more cool things about stars! Image via NASA/ ESA/ SOHO.

6. Our sun is a green star

This might seem contradictory after the last fact … But our sun is a “green” star, or more specifically, a green-blue star. That is, its peak wavelength lies clearly in the transition area on the spectrum between blue and green.

This isn’t just an idle fact, but is important because the temperature of a star is related to the color of its main emission wavelength. In the sun’s case, the surface temperature is about 5,800 kelvin (about 9,900 Fahrenheit or 5,500 Celsius), or 500 nanometers, which is a green-blue. However, as we said above, when the human eye factors in the other colors around it, the sun’s apparent color comes out as yellowish white.

7. Our sun is a dwarf star

We are accustomed to think of the sun as a “normal” star. And in many respects, it is. But did you know that it is a dwarf star? Technically, as far as normal stars go, there are only dwarf stars, giant stars and supergiant stars.

The giants and supergiants represent the terminal (old age) stages of stars. But the vast majority of stars – those in the long, mature stage of evolution called the main sequence by astronomers – are all called “dwarfs.”

There is quite a bit of range in size here, but they are all much smaller than the giants and supergiants. So technically, the sun is a dwarf star … And is sometimes called a “yellow dwarf”, in contradiction to the entry above!

8. Stars don’t twinkle

Stars often appear to twinkle (“scintillate”), especially when they are near the horizon. The brightest star, Sirius, twinkles, sparkles and flashes so much sometimes that people actually report it as a UFO.

Is twinkling a property of the stars then? No. It’s a property of Earth’s turbulent atmosphere. As the light from a star passes through the atmosphere, especially when the star appears near the horizon, it must pass through many layers of often rapidly differing density. This has the effect of deflecting the light slightly like a ball in a pinball machine. The light eventually gets to your eyes, but every deflection causes it to change slightly in color and intensity. The result is “twinkling.” Above the Earth’s atmosphere, stars do not twinkle.

9. You can see 20 quadrillion miles, at least

On a good night, you can see about 19,000,000,000,000,000 miles, easily. That’s 19 quadrillion miles, the approximate distance to the bright star Deneb in the constellation Cygnus the Swan.

Cygnus is prominent in the evening skies of summer, fall and winter. And Deneb is bright enough to be seen virtually anywhere in the Northern Hemisphere and, in fact, from almost anywhere in the inhabited world.

There is another star, Eta Carinae, that is a little more than twice as far away, or about 44 quadrillion miles. But Eta Carinae is faint, and not well placed for observers in most of the Northern Hemisphere.

Of course, we’re limiting this to just stars. Both the Andromeda galaxy and the Triangulum galaxy are also visible under certain conditions, and are roughly 15 and 18 quintillion miles away! (One quintillion is 10 raised to the power of 18.)

10. Black holes don’t suck

Many writers frequently describe black holes as “sucking in” everything around them. And it is a common worry among the ill-informed that the so-far-hypothetical “mini” black holes that may be produced by the Large Hadron Collider (LHC) would suck in everything around them in an ever-increasing vortex that would consume the Earth! In the case of the LHC, it isn’t true for a number of reasons, but black holes in general do not “suck.”

This is not just a semantic distinction, but one of process and consequence as well. The word “suck” via suction, as in the way vacuum cleaners work, is not how black holes attract matter. In a vacuum cleaner, the fan produces a partial vacuum (really, just a slightly lower pressure) at the floor end of the vacuum, and regular air pressure outside, being greater, pushes the air into it, carrying along loose dirt and dust.

In the case of black holes, there is no suction involved. Instead, matter is pulled into the black hole by a very strong gravitational attraction. In one way of visualizing it, it really is a bit like falling into a hole, but not like being hoovered into it. Gravity is a fundamental force of nature, and all matter has it. When something is pulled into a black hole, the process is more like a fish being reeled in by an angler, rather than being pushed along like a rafter inexorably being dragged over a waterfall.

The difference may seem trivial, but from a physical standpoint it is fundamental. So black holes don’t suck, but they are very cool. Actually, they are cold. Very, very cold. But that’s a story for another time.

Enjoying EarthSky? Sign up for our free daily newsletter today!

Bottom line: Here’s a collection of 10 cool things about stars that you probably didn’t know. Big stars, green stars, black holes, stars by the millions, and more!

The post Top 10 cool things about stars that you probably didn’t know first appeared on EarthSky.

from EarthSky https://ift.tt/agoN9Qi

Here we present 10 cool things about stars!

We live in uncertain times. But things are always so much more peaceful, looking up. Please help EarthSky keep going!

1. Every star you see in the night sky is bigger and brighter than our sun

Of the 5,000 or so stars bright enough to see with the unaided eye (brighter than magnitude 6) only a handful of very faint stars are near the same size and brightness of our sun. All the rest are all bigger and brighter.

Of the 500 or so that are brighter than 4th magnitude – which includes essentially every star visible to the unaided eye from an urban location – all are bigger and brighter than our sun, many by a large percentage.

Of the brightest 50 stars visible to the human eye from Earth, the least intrinsically bright star is Alpha Centauri. This star still appears very bright to us, because it’s the closest star system to Earth at 4.2 light-years away. And Alpha Centauri is still more than 1.5 times more luminous than our sun.

Read about brightness and luminosity here

2. You can’t see millions of stars on a dark night

Despite what you may hear in poems, songs and commercials, you cannot see a million stars … anywhere. There simply are not enough stars close enough and bright enough to equal a million.

On a really exceptional night, with no moon and far from any source of lights, a person with very good eyesight may be able to see 2,000-2,500 stars at any one time. So the next time you hear someone claim to have seen a million stars in the sky, just attribute it to wonder-inspired exaggeration.

3. Red hot, blue cool? No!

We are accustomed to referring to things that are red as hot and those that are blue as cool. This is not entirely unreasonable, since a red, glowing fireplace poker is hot; and ice, especially in glaciers and polar regions, can have a bluish cast. But we say that only because our everyday experience is limited.

In fact, heated objects change color as their temperature changes. And red represents the lowest temperature at which a heated object can glow in visible light. As it gets hotter, the color changes to white and ultimately to blue. So the red stars you see in the sky are the “coolest” (least hot), and the blue stars are the hottest!

4. Stars are black bodies

A black body is an object that absorbs 100% of all electromagnetic radiation (light, radio waves and so on) that falls on it. A common image here is that of a brick oven with the interior painted black and the only opening a small window. All light that shines through the window is absorbed by the interior of the oven and none is reflected outside the oven. It is a perfect absorber.

As it turns out, this definition of being a perfect absorber suits stars very well! But this just says that a black body absorbs all the radiant energy that hits it. And it does not forbid the black body from re-emitting the energy. In the case of a star, it absorbs all radiation that falls on it, but it also radiates back into space much more than it absorbs. Thus a star is a black body that glows with great brilliance!

An even more perfect black body is a black hole. But, unlike stars, a black hole appears truly black, and radiates no light.

5. There are no green stars

There are scattered claims for stars that appear green, including Beta Librae (Zubeneschamali). But most observers do not see green in any stars except as an optical effect from their telescopes, or else a quirk of personal vision and contrast.

Stars emit a spectrum (“rainbow”) of colors, including green. But the human eye-brain connection mixes the colors together in a manner that rarely, if ever, comes out green. One color can dominate the radiation, but within the range of wavelengths and intensities found in stars, greens get mixed with other colors. And in that case the star appears white. For stars, the general colors are, from lower to higher temperatures, red, orange, yellow, white and blue. So as far as the human eye can tell, there are no green stars.

The sun in extreme ultraviolet, converted to the false color green. The human eye cannot see ultraviolet at all. Keep reading for more cool things about stars! Image via NASA/ ESA/ SOHO.

6. Our sun is a green star

This might seem contradictory after the last fact … But our sun is a “green” star, or more specifically, a green-blue star. That is, its peak wavelength lies clearly in the transition area on the spectrum between blue and green.

This isn’t just an idle fact, but is important because the temperature of a star is related to the color of its main emission wavelength. In the sun’s case, the surface temperature is about 5,800 kelvin (about 9,900 Fahrenheit or 5,500 Celsius), or 500 nanometers, which is a green-blue. However, as we said above, when the human eye factors in the other colors around it, the sun’s apparent color comes out as yellowish white.

7. Our sun is a dwarf star

We are accustomed to think of the sun as a “normal” star. And in many respects, it is. But did you know that it is a dwarf star? Technically, as far as normal stars go, there are only dwarf stars, giant stars and supergiant stars.

The giants and supergiants represent the terminal (old age) stages of stars. But the vast majority of stars – those in the long, mature stage of evolution called the main sequence by astronomers – are all called “dwarfs.”

There is quite a bit of range in size here, but they are all much smaller than the giants and supergiants. So technically, the sun is a dwarf star … And is sometimes called a “yellow dwarf”, in contradiction to the entry above!

8. Stars don’t twinkle

Stars often appear to twinkle (“scintillate”), especially when they are near the horizon. The brightest star, Sirius, twinkles, sparkles and flashes so much sometimes that people actually report it as a UFO.

Is twinkling a property of the stars then? No. It’s a property of Earth’s turbulent atmosphere. As the light from a star passes through the atmosphere, especially when the star appears near the horizon, it must pass through many layers of often rapidly differing density. This has the effect of deflecting the light slightly like a ball in a pinball machine. The light eventually gets to your eyes, but every deflection causes it to change slightly in color and intensity. The result is “twinkling.” Above the Earth’s atmosphere, stars do not twinkle.

9. You can see 20 quadrillion miles, at least

On a good night, you can see about 19,000,000,000,000,000 miles, easily. That’s 19 quadrillion miles, the approximate distance to the bright star Deneb in the constellation Cygnus the Swan.

Cygnus is prominent in the evening skies of summer, fall and winter. And Deneb is bright enough to be seen virtually anywhere in the Northern Hemisphere and, in fact, from almost anywhere in the inhabited world.

There is another star, Eta Carinae, that is a little more than twice as far away, or about 44 quadrillion miles. But Eta Carinae is faint, and not well placed for observers in most of the Northern Hemisphere.

Of course, we’re limiting this to just stars. Both the Andromeda galaxy and the Triangulum galaxy are also visible under certain conditions, and are roughly 15 and 18 quintillion miles away! (One quintillion is 10 raised to the power of 18.)

10. Black holes don’t suck

Many writers frequently describe black holes as “sucking in” everything around them. And it is a common worry among the ill-informed that the so-far-hypothetical “mini” black holes that may be produced by the Large Hadron Collider (LHC) would suck in everything around them in an ever-increasing vortex that would consume the Earth! In the case of the LHC, it isn’t true for a number of reasons, but black holes in general do not “suck.”

This is not just a semantic distinction, but one of process and consequence as well. The word “suck” via suction, as in the way vacuum cleaners work, is not how black holes attract matter. In a vacuum cleaner, the fan produces a partial vacuum (really, just a slightly lower pressure) at the floor end of the vacuum, and regular air pressure outside, being greater, pushes the air into it, carrying along loose dirt and dust.

In the case of black holes, there is no suction involved. Instead, matter is pulled into the black hole by a very strong gravitational attraction. In one way of visualizing it, it really is a bit like falling into a hole, but not like being hoovered into it. Gravity is a fundamental force of nature, and all matter has it. When something is pulled into a black hole, the process is more like a fish being reeled in by an angler, rather than being pushed along like a rafter inexorably being dragged over a waterfall.

The difference may seem trivial, but from a physical standpoint it is fundamental. So black holes don’t suck, but they are very cool. Actually, they are cold. Very, very cold. But that’s a story for another time.

Enjoying EarthSky? Sign up for our free daily newsletter today!

Bottom line: Here’s a collection of 10 cool things about stars that you probably didn’t know. Big stars, green stars, black holes, stars by the millions, and more!

The post Top 10 cool things about stars that you probably didn’t know first appeared on EarthSky.

from EarthSky https://ift.tt/agoN9Qi

Dog days of summer: Hottest in July and August

The dog days of summer refer to the hottest days of the year that we experience in July and August. They’re named after the Dog Star, Sirius, the brightest star in the sky. It’s in the constellation of Canis Major, the Greater Dog. The Belt of Orion can point you to dazzling Sirius in the morning sky.

What are the dog days of summer?

You might have heard the hottest days of summer referred to as the dog days of summer … but where did this term come from? According to the National Weather Service:

The “dog days of summer” is a phrase used to describe the hot and humid days of summer. It can be traced back thousands of years to the days of the Roman Empire. It refers to the dates from July 3 through August 11, which is 20 days prior and 20 days after the star Sirius rises and falls in conjunction [sharing the same spot in our sky] with the sun. Sirius was known as the “Dog Star,” because it is the brightest star in the constellation Canis Major (Large Dog).

So, you can see the term dog days isn’t new. And its origin is based on objects in the sky.

What does Sirius have to do with the hottest days of summer?

The name Sirius comes from an ancient Greek word for “scorching” or “glowing.” It’s the brightest star visible from Earth, and skywatchers in both hemispheres can see it.

Sirius is a beacon in Northern Hemisphere winter skies. During northern summer, it lies behind the sun from Earth’s perspective. And in late summer it appears in the east before sunrise, near the sun in our sky.

Ancient Egyptians noted that Sirius rose just before the sun each year immediately prior to the annual flooding of the Nile River. Although the floods could bring destruction, they also brought new soil and new life.

Ancient Romans noticed the reappearance of Sirius in the morning sky as well. And they blamed it for the heat in July and August. That’s because Sirius rose each day before sunrise. And then, it traveled across the sky with the sun all day. Thus, early stargazers might have imagined a double-whammy from Sirius and the sun caused the hot weather.

Sirius in conjunction with the sun

Since Sirius is in conjunction with the sun on July 23, the dog days of summer center around then. The dog days of summer fall between July 3 to August 11, and that’s when we have many of our warmest days in the Northern Hemisphere.

So even though we know why this is the hottest time of the year in the Northern Hemisphere, the legend of the dog days has survived.

Bottom line: The dog days of summer are named for the Dog Star, Sirius – the brightest star in the sky – in the constellation Canis Major the Greater Dog.

The post Dog days of summer: Hottest in July and August first appeared on EarthSky.

from EarthSky https://ift.tt/NvGzWOp

The dog days of summer refer to the hottest days of the year that we experience in July and August. They’re named after the Dog Star, Sirius, the brightest star in the sky. It’s in the constellation of Canis Major, the Greater Dog. The Belt of Orion can point you to dazzling Sirius in the morning sky.

What are the dog days of summer?

You might have heard the hottest days of summer referred to as the dog days of summer … but where did this term come from? According to the National Weather Service:

The “dog days of summer” is a phrase used to describe the hot and humid days of summer. It can be traced back thousands of years to the days of the Roman Empire. It refers to the dates from July 3 through August 11, which is 20 days prior and 20 days after the star Sirius rises and falls in conjunction [sharing the same spot in our sky] with the sun. Sirius was known as the “Dog Star,” because it is the brightest star in the constellation Canis Major (Large Dog).

So, you can see the term dog days isn’t new. And its origin is based on objects in the sky.

What does Sirius have to do with the hottest days of summer?

The name Sirius comes from an ancient Greek word for “scorching” or “glowing.” It’s the brightest star visible from Earth, and skywatchers in both hemispheres can see it.

Sirius is a beacon in Northern Hemisphere winter skies. During northern summer, it lies behind the sun from Earth’s perspective. And in late summer it appears in the east before sunrise, near the sun in our sky.

Ancient Egyptians noted that Sirius rose just before the sun each year immediately prior to the annual flooding of the Nile River. Although the floods could bring destruction, they also brought new soil and new life.

Ancient Romans noticed the reappearance of Sirius in the morning sky as well. And they blamed it for the heat in July and August. That’s because Sirius rose each day before sunrise. And then, it traveled across the sky with the sun all day. Thus, early stargazers might have imagined a double-whammy from Sirius and the sun caused the hot weather.

Sirius in conjunction with the sun

Since Sirius is in conjunction with the sun on July 23, the dog days of summer center around then. The dog days of summer fall between July 3 to August 11, and that’s when we have many of our warmest days in the Northern Hemisphere.

So even though we know why this is the hottest time of the year in the Northern Hemisphere, the legend of the dog days has survived.

Bottom line: The dog days of summer are named for the Dog Star, Sirius – the brightest star in the sky – in the constellation Canis Major the Greater Dog.

The post Dog days of summer: Hottest in July and August first appeared on EarthSky.

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Huge magma systems on Mars existed below the surface

View larger. | This Mars Express spacecraft view shows Olympus Mons on Mars, the largest volcano in the solar system. A new study has revealed that Mars’ volcanoes – now dormant – were once not as disconnected as 1st thought. Instead, they were intertwined by vast magma systems below the surface. These magma systems on Mars spanned throughout the northern hemisphere’s crust. Image via ESA/ DLR/ FU Berlin/ J. Cowart.

• Mars has many volcanoes, just like Earth. Scientists have long thought that these volcanoes, back when they were still active, were relatively simple and disconnected from each other.
• But a new study of data from the InSight lander mission shows that there were vast, interconnected magma systems below the Martian surface.
• That would mean Mars’ volcanic systems were more earthlike than previously thought, despite the planet not having plate tectonics.

EarthSky isn’t powered by billionaires. We’re powered by you. Support EarthSky’s 2026 Donation Campaign and help keep science accessible.

Huge ancient magma systems on Mars

Like Earth, Mars has numerous volcanoes dotting its surface. As far as we know, those volcanoes are now extinct. And scientists have long thought the planet’s volcanic system overall was simpler than Earth’s, since Mars lacks plate tectonics. But now there’s evidence that isn’t quite true.

Scientists at the University of Oxford in the U.K. said on June 26, 2026, they’ve found evidence that Mars once had enormous, Earth-like magma systems – interconnected zones of molten rock – deep beneath its surface.

Scientists have long categorized Mars as a stagnant lid planet. That means it has one large solid surface, or “lid,” instead of the surface being broken into smaller tectonic plates like on Earth. On Earth, plate tectonics drives volcanism, recycling and continent–building.

But this new study points to huge, interconnected magma systems. They show that Mars’ volcanoes weren’t just simple isolated formations as previously assumed. And they force us to ask … How did this occur without plate tectonics?

Lead author Tobermory Mackay-Champion at the University of Oxford said:

We’ve traditionally assumed that volcanism on Mars was relatively simple compared to that on Earth. But this discovery suggests the planet could sustain massive, long-lived magmatic systems capable of evolving and reprocessing molten rock throughout the crust. Because these systems are known to generate large metal deposits, Mars may hold significantly more near-surface mineral wealth than previously recognised, boosting its potential for future mining, crewed missions and eventually, permanent settlements.

The researchers published their peer-reviewed findings in Nature Astronomy on June 26, 2026.

NEW: Mars may have been far more Earth-like beneath its surface than scientists once thought ??Oxford researchers have uncovered evidence of vast hidden magma systems that could reshape our understanding of how rocky planets evolve ??https://bit.ly/4wwd4jx

— University of Oxford (@ox.ac.uk) 2026-06-26T13:26:02.740122411Z

InSight spacecraft data provides clues

The researchers made the discovery when analyzing data from NASA’s InSight lander. InSight ended its mission in 2022, but there is still a ton of data to study. The lander recorded seismic waves from marsquakes and meteorite impacts.

The researchers used the data to investigate an unusual boundary about 15 miles (24 km) below the surface. Scientists knew about the boundary before, but didn’t know what it was. One possibility is that it marked a transition between two different types of rock. To test this, the researchers compared hundreds of different rock compositions with the seismic data.

Mike Kendall, Tobermory Mackay Champion (lead author) and Jon Wade at the University of Oxford. Image via University of Oxford.

Very different rocks below the boundary

The results showed that there was indeed a boundary between two types of rock. Below the boundary, the rocks were ultramafic, meaning rich in iron and magnesium. But interestingly, the rocks above the boundary were quite different. They were mafic rocks, rich in silica.

Why is the rock layer below the boundary so different from the layer above? The researchers say that molten rock likely pooled there. Then, it gradually separated into different materials over time. This left behind a residue of dense crystals at the base of the crust. Meanwhile, lighter molten rock moved upwards. This is similar to what happens on Earth beneath volcanic arcs. This is also linked to the formation of continents, although Mars never got to that stage.

View larger. | Illustration depicting NASA’s InSight lander on Mars, with a cutaway view of the subsurface. Image via PGP/ Nicolas Sarter/ Jet Propulsion Laboratory/ NASA.

Vast magma layer across the northern hemisphere

The researchers say this magma layer was vast, spanning hundreds of miles sideways beneath the surface. That means that instead of Mars’ volcanoes being isolated, they were actually interconnected by these sprawling magma systems. On Earth, this is known as transcrustal magmatism. Until now, scientists only knew of it occurring on one planet: Earth.

But if it happened on Mars too, that raises questions about how rocky planets form and if they can be habitable. Co-author Jon Wade at the University of Oxford said:

One of the big questions in planetary science is whether Earth is unique. If Mars could develop this kind of complex crust without plate tectonics, then maybe the conditions needed for habitability can emerge on more planets than we realised, including those previously dismissed based on size or their apparent lack of tectonic activity.

In 2024, scientists reported evidence for magma possibly still existing beneath Olympus Mons, the largest volcano on Mars. If so, it would mean that there is still some residual tectonic and volcanic activity below the surface today. Mars might still be alive, at least geologically!

Bottom line: Scientists have found evidence of enormous ancient magma systems on Mars. They show that Mars’ volcanic systems were once more complex than first thought.

Source: Seismic evidence for a melt-depleted lower crust and transcrustal magmatism on Mars

Via University of Oxford

Read more:

Ancient volcanoes on Mars were diverse

The most recent volcanoes on Mars were surprisingly active

34 dust devils on Mars in 1 shot! Can you spot them all?

The post Huge magma systems on Mars existed below the surface first appeared on EarthSky.

from EarthSky https://ift.tt/mdAGlMO

View larger. | This Mars Express spacecraft view shows Olympus Mons on Mars, the largest volcano in the solar system. A new study has revealed that Mars’ volcanoes – now dormant – were once not as disconnected as 1st thought. Instead, they were intertwined by vast magma systems below the surface. These magma systems on Mars spanned throughout the northern hemisphere’s crust. Image via ESA/ DLR/ FU Berlin/ J. Cowart.

• Mars has many volcanoes, just like Earth. Scientists have long thought that these volcanoes, back when they were still active, were relatively simple and disconnected from each other.
• But a new study of data from the InSight lander mission shows that there were vast, interconnected magma systems below the Martian surface.
• That would mean Mars’ volcanic systems were more earthlike than previously thought, despite the planet not having plate tectonics.

EarthSky isn’t powered by billionaires. We’re powered by you. Support EarthSky’s 2026 Donation Campaign and help keep science accessible.

Huge ancient magma systems on Mars

Like Earth, Mars has numerous volcanoes dotting its surface. As far as we know, those volcanoes are now extinct. And scientists have long thought the planet’s volcanic system overall was simpler than Earth’s, since Mars lacks plate tectonics. But now there’s evidence that isn’t quite true.

Scientists at the University of Oxford in the U.K. said on June 26, 2026, they’ve found evidence that Mars once had enormous, Earth-like magma systems – interconnected zones of molten rock – deep beneath its surface.

Scientists have long categorized Mars as a stagnant lid planet. That means it has one large solid surface, or “lid,” instead of the surface being broken into smaller tectonic plates like on Earth. On Earth, plate tectonics drives volcanism, recycling and continent–building.

But this new study points to huge, interconnected magma systems. They show that Mars’ volcanoes weren’t just simple isolated formations as previously assumed. And they force us to ask … How did this occur without plate tectonics?

Lead author Tobermory Mackay-Champion at the University of Oxford said:

We’ve traditionally assumed that volcanism on Mars was relatively simple compared to that on Earth. But this discovery suggests the planet could sustain massive, long-lived magmatic systems capable of evolving and reprocessing molten rock throughout the crust. Because these systems are known to generate large metal deposits, Mars may hold significantly more near-surface mineral wealth than previously recognised, boosting its potential for future mining, crewed missions and eventually, permanent settlements.

The researchers published their peer-reviewed findings in Nature Astronomy on June 26, 2026.

NEW: Mars may have been far more Earth-like beneath its surface than scientists once thought ??Oxford researchers have uncovered evidence of vast hidden magma systems that could reshape our understanding of how rocky planets evolve ??https://bit.ly/4wwd4jx

— University of Oxford (@ox.ac.uk) 2026-06-26T13:26:02.740122411Z

InSight spacecraft data provides clues

The researchers made the discovery when analyzing data from NASA’s InSight lander. InSight ended its mission in 2022, but there is still a ton of data to study. The lander recorded seismic waves from marsquakes and meteorite impacts.

The researchers used the data to investigate an unusual boundary about 15 miles (24 km) below the surface. Scientists knew about the boundary before, but didn’t know what it was. One possibility is that it marked a transition between two different types of rock. To test this, the researchers compared hundreds of different rock compositions with the seismic data.

Mike Kendall, Tobermory Mackay Champion (lead author) and Jon Wade at the University of Oxford. Image via University of Oxford.

Very different rocks below the boundary

The results showed that there was indeed a boundary between two types of rock. Below the boundary, the rocks were ultramafic, meaning rich in iron and magnesium. But interestingly, the rocks above the boundary were quite different. They were mafic rocks, rich in silica.

Why is the rock layer below the boundary so different from the layer above? The researchers say that molten rock likely pooled there. Then, it gradually separated into different materials over time. This left behind a residue of dense crystals at the base of the crust. Meanwhile, lighter molten rock moved upwards. This is similar to what happens on Earth beneath volcanic arcs. This is also linked to the formation of continents, although Mars never got to that stage.

View larger. | Illustration depicting NASA’s InSight lander on Mars, with a cutaway view of the subsurface. Image via PGP/ Nicolas Sarter/ Jet Propulsion Laboratory/ NASA.

Vast magma layer across the northern hemisphere

The researchers say this magma layer was vast, spanning hundreds of miles sideways beneath the surface. That means that instead of Mars’ volcanoes being isolated, they were actually interconnected by these sprawling magma systems. On Earth, this is known as transcrustal magmatism. Until now, scientists only knew of it occurring on one planet: Earth.

But if it happened on Mars too, that raises questions about how rocky planets form and if they can be habitable. Co-author Jon Wade at the University of Oxford said:

One of the big questions in planetary science is whether Earth is unique. If Mars could develop this kind of complex crust without plate tectonics, then maybe the conditions needed for habitability can emerge on more planets than we realised, including those previously dismissed based on size or their apparent lack of tectonic activity.

In 2024, scientists reported evidence for magma possibly still existing beneath Olympus Mons, the largest volcano on Mars. If so, it would mean that there is still some residual tectonic and volcanic activity below the surface today. Mars might still be alive, at least geologically!

Bottom line: Scientists have found evidence of enormous ancient magma systems on Mars. They show that Mars’ volcanic systems were once more complex than first thought.

Source: Seismic evidence for a melt-depleted lower crust and transcrustal magmatism on Mars

Via University of Oxford

Read more:

Ancient volcanoes on Mars were diverse

The most recent volcanoes on Mars were surprisingly active

34 dust devils on Mars in 1 shot! Can you spot them all?

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Exquisite Albireo, a beloved and colorful double star

View at EarthSky Community Photos. | David Hoskin of Halifax, Nova Scotia, Canada, captured this image on June 29, 2024, and wrote: “Albireo (Beta Cygni) is a colorful double star in the constellation Cygnus.” Thank you, David!

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Albireo offers a beautiful color contrast

Albireo, also known as Beta Cygni, is the 2nd-brightest star in the constellation Cygnus the Swan. At first glance, it doesn’t particularly stand out. But viewing this star through a small telescope can take your breath away. Indeed, it resolves into a striking pair of stars, one a lovely gold and the other a dimmer blue.

The two stars appear close in the sky from our perspective, but scientists aren’t sure that they’re gravitationally bound to each other. Regardless, the striking color contrast between the close pair makes Albireo one of the most beautiful double stars in our sky.

The bright star Deneb is part of the famous Summer Triangle asterism. Its constellation, Cygnus the Swan, flies across the July evening sky.

How to find Albireo

How can you spot Albireo in the night sky? It’s easy to find if you can locate Cygnus the Swan. Cygnus is known for containing an easily recognizable cross shape, known as the Northern Cross. The brightest star in Cygnus, Deneb, marks the top of the Cross, or the Tail of the Swan. Albireo, meanwhile, marks the base of the Cross or the Head of Cygnus the Swan.

And how can you see Albireo as two stars? Unless you have exceedingly powerful binoculars mounted on a tripod, binoculars unfortunately won’t show you Albireo as two stars. But any small telescope will. It’s best to view them at 30X (“30 power” or a magnification of 30). And when you see Albireo as two stars, be sure to notice the striking color contrast between the two.

A star map of Cygnus. Image via Wikimedia.

Science of Albireo

The brighter, golden star – Albireo A – is about 400 light-years away. Albireo B, the dimmer blue star, is around 400 light-years distant. And although this is not confirmed, Albireo A and B are thought to only be a pair from our perspective, rather than being a gravitationally bound binary system.

But on the other hand, Albireo A itself is a binary star, formed of two stars so close together that you can’t see them separately. These stars take 121.6 years to orbit one another. The brighter star of the two is responsible for the gold color you see through a telescope. It’s a red supergiant star, about 5 times the mass of the sun. It shines at magnitude 3.21. And it outshines its fainter companion, a hot main sequence star that’s 2.7 times the sun’s mass.

Furthermore, in a recent analysis of the Albireo A binary system, astronomers were surprised to find that there might be more stars in the system, possibly making Albireo A a triple or quadruple star system.

Albireo B, the fainter blue star of the pair when viewed through a small telescope, appears just 34 arc seconds away from gold-colored Albireo A. It’s a hot blue star with about 3.7 times the sun’s mass. It shines at magnitude 5.11. If it is a physical companion star to Albireo A, their orbital period would take about 100,000 years.

Bottom line: Albireo, in the constellation Cygnus, is a favorite for stargazers. Through a small telescope, it appears as a beautiful golden star with a dimmer blue companion.

The post Exquisite Albireo, a beloved and colorful double star first appeared on EarthSky.

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View at EarthSky Community Photos. | David Hoskin of Halifax, Nova Scotia, Canada, captured this image on June 29, 2024, and wrote: “Albireo (Beta Cygni) is a colorful double star in the constellation Cygnus.” Thank you, David!

Science matters. Wonder matters. You matter. Join our 2026 Donation Campaign today.

Albireo offers a beautiful color contrast

Albireo, also known as Beta Cygni, is the 2nd-brightest star in the constellation Cygnus the Swan. At first glance, it doesn’t particularly stand out. But viewing this star through a small telescope can take your breath away. Indeed, it resolves into a striking pair of stars, one a lovely gold and the other a dimmer blue.

The two stars appear close in the sky from our perspective, but scientists aren’t sure that they’re gravitationally bound to each other. Regardless, the striking color contrast between the close pair makes Albireo one of the most beautiful double stars in our sky.

The bright star Deneb is part of the famous Summer Triangle asterism. Its constellation, Cygnus the Swan, flies across the July evening sky.

How to find Albireo

How can you spot Albireo in the night sky? It’s easy to find if you can locate Cygnus the Swan. Cygnus is known for containing an easily recognizable cross shape, known as the Northern Cross. The brightest star in Cygnus, Deneb, marks the top of the Cross, or the Tail of the Swan. Albireo, meanwhile, marks the base of the Cross or the Head of Cygnus the Swan.

And how can you see Albireo as two stars? Unless you have exceedingly powerful binoculars mounted on a tripod, binoculars unfortunately won’t show you Albireo as two stars. But any small telescope will. It’s best to view them at 30X (“30 power” or a magnification of 30). And when you see Albireo as two stars, be sure to notice the striking color contrast between the two.

A star map of Cygnus. Image via Wikimedia.

Science of Albireo

The brighter, golden star – Albireo A – is about 400 light-years away. Albireo B, the dimmer blue star, is around 400 light-years distant. And although this is not confirmed, Albireo A and B are thought to only be a pair from our perspective, rather than being a gravitationally bound binary system.

But on the other hand, Albireo A itself is a binary star, formed of two stars so close together that you can’t see them separately. These stars take 121.6 years to orbit one another. The brighter star of the two is responsible for the gold color you see through a telescope. It’s a red supergiant star, about 5 times the mass of the sun. It shines at magnitude 3.21. And it outshines its fainter companion, a hot main sequence star that’s 2.7 times the sun’s mass.

Furthermore, in a recent analysis of the Albireo A binary system, astronomers were surprised to find that there might be more stars in the system, possibly making Albireo A a triple or quadruple star system.

Albireo B, the fainter blue star of the pair when viewed through a small telescope, appears just 34 arc seconds away from gold-colored Albireo A. It’s a hot blue star with about 3.7 times the sun’s mass. It shines at magnitude 5.11. If it is a physical companion star to Albireo A, their orbital period would take about 100,000 years.

Bottom line: Albireo, in the constellation Cygnus, is a favorite for stargazers. Through a small telescope, it appears as a beautiful golden star with a dimmer blue companion.

The post Exquisite Albireo, a beloved and colorful double star first appeared on EarthSky.

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