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Astra to begin three-launch campaign with NASA hurricane research satellites – Spaceflight Now

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Astra’s Rocket 3.3, tail number LV0010, stands its launch pad at Cape Canaveral Space Force Station before launch on NASA’s TROPICS-1 mission. Credit: Brady Kenniston / Astra

Astra is preparing to launch the first of three straight dedicated missions for NASA this weekend at Cape Canaveral to deploy six shoebox-size hurricane research satellites, helping pioneer a new paradigm of riskier but less expensive science missions.

The commercial launch company, geared toward the burgeoning small satellite industry, won a $7.95 million contract last year to haul NASA’s six TROPICS spacecraft into orbit using three rockets.

The first of the three TROPICS missions is set for liftoff during a two-hour window opening at 12 p.m. EDT (1600 GMT) Sunday. Forecasters predict stormy weather at the launch site, with a greater than 50% chance conditions could prevent liftoff. Conditions should improve Monday, according to the official launch weather outlook.

Astra delivered the rocket to Florida’s Space Coast last month from its California factory, then completed a test-firing of the booster’s five engines at Space Launch Complex 46, a commercially-operated facility near the easternmost extent of Cape Canaveral Space Force Station.

The first two TROPICS satellites are mounted inside a deployer on top of the 43-foot-tall (13.1-meter) Astra launcher, which the company calls Rocket 3.3, or tail number LV0010.

“We’re trying to make improved observations of tropical cyclones,” said William Blackwell, principal investigator for the TROPICS mission from MIT Lincoln Laboratory. “And what we’re really trying to characterize is the fundamental thermodynamic environment around the storm. So that’s things like the temperature, and the amount of moisture and precipitation intensity, and the structure around the storm.

“Those are important variables because they can be related to the intensity of the storm, and even potential for future intensification,” Blackwell said in Friday in an interview with Spaceflight Now. “So we’re trying to make those measurements with relatively high revisit. That’s really the key new feature that the TROPICS constellation provides, is improved revisit of the storms.

“We’ll have six satellites orbiting, and one satellite will work to make a nice image of the storm, and then the next satellite will orbit closely behind it about an hour behind,” Blackwell said. “So we’ll get, roughly every hour, a new image of the storm, and that’s about a factor of five-to-eight better than what we get today. With these new measurements of rapidly updated imagery, we hope that that will help us understand the storm better, and ultimately lead to better forecasting of the hurricane track and intensity.”

TROPICS stands for Time-Resolved Observations of Precipitation structure and storm Intensity with a Constellation of Smallsats. The mission has a total cost of approximately $30 million, according to NASA.

Each TROPICS satellite has a single instrument. A microwave radiometer, about the size of a coffee cup and spinning 30 times per minute, will create images of tropical cyclones, collect temperature measurements, and gather vertical profiles of moisture through the atmosphere.

“I love TROPICS, just because it’s kind of a crazy mission,” said Thomas Zurbuchen, head of NASA’s science mission directorate. “Think of six CubeSats doing science, looking at tropical storms with a repeat time of 50 minutes.”

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“NOAA and the Europeans and many others have been flying passive microwave radiometers for decades, and these are big, expensive instruments,” Blackwell said. “What we’ve done with TROPICS is miniaturize the electronics to make them much smaller.

“The entire satellite for TROPICS, one of them weighs about 10 pounds, and is about the size of a loaf of bread,” Blackwell said. “So these are relatively inexpensive to build and test, and we can make them fairly rapidly, and they’re relatively inexpensive to launch.”

The TROPICS satellites were built by Blue Canyon Technologies in Boulder, Colorado. Their small size makes them a good fit for Astra, which can deliver about 110 pounds (50 kilograms) of payload to a 310-mile-high (500-kilometer) orbit. Astra’s rocket is the smallest orbital-class launcher currently flying.

Astra will launch two TROPICS satellites at a time, flying missions at several-week intervals. If all goes well, the launches should be completed by the end of July.

The satellites will launch into orbit 357 miles (550 kilometers) above Earth, circling the planet at an angle 29.75 degrees to the equator. The low-inclination orbit will focus the TROPICS observations on hotspots for tropical cyclone development.

The second and third TROPICS launches — currently planned for late June and mid-July — will aim to deploy the next four satellites into precise orbital planes, giving the constellation the proper spacing to enable regular flyovers of cyclones.

Many CubeSats ride to space on rideshare launches, allowing operators to take advantage of lower costs by bundling their payloads on a single large rocket. But the TROPICS satellites need dedicated launches to reach their precise orbital destinations.

“We want to space out the spacecraft as much as we can, and want to keep them over the tropical cyclone belt,” Blackwell said. “This overall configuration lets us do that, but it requires three separate dedicated launchers.”

Astra beat out bids from SpaceX, Rocket Lab, Virgin Orbit, and Momentus, largely due to their lower-cost proposal, according to NASA.

“NASA selected Astra because of our unique ability to get to three different orbital planes in a very short period of time, at a low cost,” said Martin Attiq, Astra’s chief business officer. “So being able to launch three different times for $8 million is unprecedented.”

Artist’s illustration of the TROPICS satellite constellation. Credit: NASA / MIT Lincoln Laboratory

Founded in 2016, Astra aims to eventually launch daily missions to carry small satellites into orbit for a range of customers, including the U.S. military, commercial companies, and NASA. The company has successfully reached orbit in two of six tries.

Astra’s most recent flight in March marked the first time the company placed functioning satellites into orbit, following a liftoff from Kodiak Island, Alaska. The previous Astra launch in February, which departed Cape Canaveral, failed to place a payload of NASA-sponsored CubeSats into orbit.

NASA officials are aware of the risk of flying satellites on a new, relatively unproven launcher. TROPICS is part of NASA’s Earth Venture program, a series of cost-capped missions designed for Earth science research. NASA assumes more risk for Venture-class missions.

“Only four of the spacecraft need to work, so two rockets need to work,” Zurbuchen said. “This is a different risk level than what we do in so many other things in which we kind of focus, flatten the risk, and pound it down as much as we can. And that is deliberate. It’s deliberate because speed matters when you’re in the innovation game, and we want new capabilities and new assets and new tools.”

NASA selected TROPICS for development in 2016.

“We’ve designed the mission from the ground up to build in some robustness to failure,” Blackwell said. “The choice of six satellites was made to give us some margin. We only needed four to meet our baseline requirements, so we can tolerate failures of the satellite or failures of the launch, or whatever, and we can still meet our requirements.”

Astra’s first launch with two TROPICS satellites will begin with the ignition of Rocket 3.3’s five kerosene-fueled engines at pad 46. The Delphin engines will drive the launcher off the pad with 32,500 pounds of thrust, powering the rocket downrange to the east-northeast from Cape Canaveral.

First stage engine cutoff is expected three minutes after liftoff, followed by separation of the rocket’s payload shroud, which covers the upper stage and the TROPICS payloads during the climb through the atmosphere. Then rocket’s booster stage will jettison to fall into the Atlantic, allowing the upper stage to ignite for a five-minute burn to accelerate to orbital velocity.

Deployment the TROPICS satellites is scheduled at T+plus 8 minutes, 40 seconds, according to a mission timeline posted by Astra.

The six TROPICS CubeSats. Credit: Blue Canyon Technologies

The satellites will unfurl solar panels to begin generating electricity, and ground teams will run the TROPICS spacecraft through tests and checkouts.

If the three TROPICS launches get off the ground as scheduled, the satellites should all be collecting by August, just in time for the peak of the Atlantic hurricane season, according to Will McCarty, NASA’s program scientist for the mission. The mission is designed for at least one year of science observations.

“We’re, of course, highly motivated to get the data out as soon as we can because we’re going to be in the throes of Atlantic hurricane season, so there’s going be a lot of demand for that data,” Blackwell said.

A pathfinder satellite for the TROPICS mission launched last June on a SpaceX rideshare mission, and has performed well in orbit, collecting test measurements of temperature and moisture over multiple tropical cyclones, including Hurricane Ida before it made landfall in Louisiana.

The experience with the TROPICS pathfinder satellites builds confidence that the six operational satellites will work, McCarty said.

“Our requirement from NASA is to collect science data for one year, and we hope to go longer than that,” Blackwell said. “There are some cases where these CubeSats are lasting three years, or even more, so we hope it will be significantly longer than than the one-year requirement.”

Email the author.

Follow Stephen Clark on Twitter: @StephenClark1.



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Science

Research reveals the science behind this plant’s blue berries

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Lantana strigocamara in the Ramaley Greenhouse on the CU Boulder campus. Credit: Patrick Campbell / CU Boulder

On a beautiful fall day in 2019, Miranda Sinnott-Armstrong was walking down Pearl Street in Boulder, Colorado when something caught her eye: a small, particularly shiny blue fruit, on a shrub known as Lantana strigocamara. While its tiny clusters of pink, yellow and orange flowers and blue berries commonly adorn the pedestrian mall in spring, city workers were ripping these common Lantanas out to prepare for the winter season.

Sinnott-Armstrong, postdoctoral researcher of ecology and evolutionary biology at CU Boulder, quickly asked if she could take a specimen back to the lab. She wanted to know: What made these berries so blue?

Sinnott-Armstrong’s results are now published in the journal New Phytologist. The study confirms Lantana strigocamara as the second-ever documented case of a plant creating blue-colored fruits with layered fat molecules. She and her co-authors published the first-ever documented case, in Viburnum tinus, in 2020.

The two plants are among only six in the world known to make their fruits’ hues using a trick of the light known as structural color. But Sinnott-Armstrong has a hunch there are more.

“We’re literally finding these things in our backyards and on our streets, people just haven’t been looking for structurally colored plants,” said Miranda Sinnott-Armstrong, lead author on the new study. “And yet, just walking on Pearl Street, you’re like, ‘Oh, there’s one!'”

Structural color is very common in animals. It’s what gives peacocks’ otherwise brown feathers their brilliant greens, and many butterflies their bright blues. But this optical illusion of sorts is much rarer in plants, according to Sinnott-Armstrong.

Stacey Smith, co-author on the publication and associate professor of ecology and evolutionary biology, peels the skin off of a Lantana fruit. Credit: Patrick Campbell / CU Boulder

To create its unique color, these blue fruits use microscopic structures in their skin to manipulate light and reflect the wavelengths our eyes perceive as blue, giving it a distinctive metallic finish. Pigmented color does the opposite, absorbing select visible wavelengths of light. This means structurally-colored berries have no color within themselves; if you were to squish them, they would not stain blue.

In fact, if you peel the skin off a Lantana fruit and hold it up to the light, it looks completely translucent. But if you place it against a dark background, it looks blue again, due to the nanostructures on the surface responsible for reflecting the color.

The evolution of color

What’s especially unique about Lantana strigocamara—besides the fact that the color blue is quite scarce in nature, especially in fruits—is that it creates this structural color in its skin using layers of lipid molecules, or fats.

Stacey Smith, co-author on the publication and associate professor of ecology and evolutionary biology, peels the skin off of a Lantana fruit. Credit: Patrick Campbell / CU Boulder

Viburnum tinus is the only other plant known to do the same thing, and Lantana and Viburnum last shared a common ancestor more than 100 million years ago. Meaning, the two plants evolved this shared trait completely independent of one another.

“It puts us on the hunt for other groups where this happens, because we know it can be done multiple ways,” said Stacey Smith, co-author on the publication and associate professor of ecology and evolutionary biology.

The researchers also chat often about why such a thing would evolve. Does structural color provide an evolutionary advantage?

Some theorize that structural color could help with seed dispersal. While there are very few known structurally colored plants, they are globally widespread. Lantana itself is invasive in many parts of the world, especially in tropical regions. It’s possible that the metallic, shiny nature of the fruit provides strong contrast with surrounding foliage, attracting animals to eat them and disperse their seeds, according to the researchers.

Lantana strigocamara in the Ramaley Greenhouse on the CU Boulder campus. Credit: Patrick Campbell / CU Boulder

“But just being blue and sparkly might be enough for an animal to think it’s decorative,” said Smith.

The researchers noted that many birds, especially in Australia, like to use structurally colored fruits to adorn their bowers and attract mates. Humans, interestingly, may also be contributing to the spread of Lantana for the same reason.

“The fact that they made their way into horticulture suggests that we are susceptible to the same things are that other animals find attractive about them,” said Smith. “We’re like, oh, look at that sparkly, cute thing. I should put that in my garden.”

Another possibility is that the thick, fatty layer which creates this unique color is a protective mechanism for the plant, providing defense against pathogens or improving the structural integrity of the fruit, said Sinnott-Armstrong.

  • Stacey Smith, co-author on the publication and associate professor of ecology and evolutionary biology, in the Ramaley Greenhouse at CU Boulder. Credit: Patrick Campbell / CU Boulder
  • Stacey Smith, co-author on the publication and associate professor of ecology and evolutionary biology, peels the skin off of a Lantana fruit. Credit: Patrick Campbell / CU Boulder

The color blue itself could also be a clue.

Pigmented and structural color are not mutually exclusive in plants, but perhaps plants stumbled across structural color as a way to make blue because it’s not as easy to create in other ways, she said.

Some researchers in Silvia Vignolini’s lab at the University of Cambridge—where Sinnott-Armstrong is currently based—are now trying to make colored paints, fabrics and more out of structural color, by better understanding the assembly of cellulose nanocrystals in colored fruits.

Researchers hope to learn more about the possible evolutionary prompts for this mechanism, as more structurally colored fruits are discovered.

“They’re out there,” said Sinnott-Armstrong. “We just haven’t seen them all yet.”

Co-authors on this publication include: Yu Ogawa, Université de Grenoble Alps; Gea Theodora van de Kerkhof, University of Cambridge; and Silvia Vignolini, University of Cambridge.

This fruit attracts birds with an unusual way of making itself metallic blue

More information:
Miranda A. Sinnott‐Armstrong et al, Convergent evolution of disordered lipidic structural colour in the fruits of Lantana strigocamara (syn. L. camara hybrid cultivar), New Phytologist (2022). DOI: 10.1111/nph.18262
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Research reveals the science behind this plant’s blue berries (2022, June 10)
retrieved 12 June 2022
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Astronomers may have detected a ‘dark’ free-f

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image: Hubble Space Telescope image of a distant star that was brightened and distorted by an invisible but very compact and heavy object between it and Earth. The compact object — estimated by UC Berkeley astronomers to be between 1.6 and 4.4 times the mass of our sun — could be a free-floating black hole, one of perhaps 200 million in the Milky Way galaxy.
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Credit: Image courtesy of STScI/NASA/ESA

If, as astronomers believe, the death of large stars leave behind black holes, there should be hundreds of millions of them scattered throughout the Milky Way galaxy. The problem is, isolated black holes are invisible.

Now, a team led by University of California, Berkeley, astronomers has for the first time discovered what may be a free-floating black hole by observing the brightening of a more distant star as its light was distorted by the object’s strong gravitational field — so-called gravitational microlensing.

The team, led by graduate student Casey Lam and Jessica Lu, a UC Berkeley associate professor of astronomy, estimates that the mass of the invisible compact object is between 1.6 and 4.4 times that of the sun. Because astronomers think that the leftover remnant of a dead star must be heavier than 2.2 solar masses in order to collapse to a black hole, the UC Berkeley researchers caution that the object could be a neutron star instead of a black hole. Neutron stars are also dense, highly compact objects, but their gravity is balanced by internal neutron pressure, which prevents further collapse to a black hole.

Whether a black hole or a neutron star, the object is the first dark stellar remnant — a stellar “ghost” — discovered wandering through the galaxy unpaired with another star.

“This is the first free-floating black hole or neutron star discovered with gravitational microlensing,” Lu said. “With microlensing, we’re able to probe these lonely, compact objects and weigh them. I think we have opened a new window onto these dark objects, which can’t be seen any other way.”

Determining how many of these compact objects populate the Milky Way galaxy will help astronomers understand the evolution of stars — in particular, how they die — and of our galaxy, and perhaps reveal whether any of the unseen black holes are primordial black holes, which some cosmologists think were produced in large quantities during the Big Bang.

The analysis by Lam, Lu and their international team has been accepted for publication in The Astrophysical Journal Letters. The analysis includes four other microlensing events that the team concluded were not caused by a black hole, though two were likely caused by a white dwarf or a neutron star. The team also concluded that the likely population of black holes in the galaxy is 200 million — about what most theorists predicted.

Same data, different conclusions

Notably, a competing team from the Space Telescope Science Institute (STScI) in Baltimore analyzed the same microlensing event and claims that the mass of the compact object is closer to 7.1 solar masses and indisputably a black hole. A paper describing the analysis by the STScI team, led by Kailash Sahu, has been accepted for publication in The Astrophysical Journal.

Both teams used the same data: photometric measurements of the distant star’s brightening as its light was distorted or “lensed” by the super-compact object, and astrometric measurements of the shifting of the distant star’s location in the sky as a result of the gravitational distortion by the lensing object. The photometric data came from two microlensing surveys: the Optical Gravitational Lensing Experiment (OGLE), which employs a 1.3-meter telescope in Chile operated by Warsaw University, and the Microlensing Observations in Astrophysics (MOA) experiment, which is mounted on a 1.8-meter telescope in New Zealand operated by Osaka University. The astrometric data came from NASA’s Hubble Space Telescope. STScI manages the science program for the telescope and conducts its science operations.

Because both microlensing surveys caught the same object, it has two names: MOA-2011-BLG-191 and OGLE-2011-BLG-0462, or OB110462, for short.

While surveys like these discover about 2,000 stars brightened by microlensing each year in the Milky Way galaxy, the addition of astrometric data is what allowed the two teams to determine the mass of the compact object and its distance from Earth. The UC Berkeley-led team estimated that it lies between 2,280 and 6,260 light years (700-1920 parsecs) away, in the direction of the center of the Milky Way Galaxy and near the large bulge that surrounds the galaxy’s central massive black hole.

The STScI group estimated that it lies about 5,153 light years (1,580 parsecs) away.

Looking for a needle in a haystack

Lu and Lam first became interested in the object in 2020 after the STScI team tentatively concluded that five microlensing events observed by Hubble — all of which lasted for more than 100 days, and thus could have been black holes — might not be caused by compact objects after all.

Lu, who has been looking for free-floating black holes since 2008, thought the data would help her better estimate their abundance in the galaxy, which has been roughly estimated at between 10 million and 1 billion. To date, star-sized black holes have been found only as part of binary star systems. Black holes in binaries are seen either in X-rays, produced when material from the star falls onto the black hole, or by recent gravitational wave detectors, which are sensitive to mergers of two or more black holes. But these events are rare.

“Casey and I saw the data and we got really interested. We said, ‘Wow, no black holes. That’s amazing,’ even though there should have been,” Lu said. “And so, we started looking at the data. If there were really no black holes in the data, then this wouldn’t match our model for how many black holes there should be in the Milky Way. Something would have to change in our understanding of black holes — either their number or how fast they move or their masses.”

When Lam analyzed the photometry and astrometry for the five microlensing events, she was surprised that one, OB110462, had the characteristics of a compact object: The lensing object seemed dark, and thus not a star; the stellar brightening lasted a long time, nearly 300 days; and the distortion of the background star’s position also was long-lasting.

The length of the lensing event was the main tipoff, Lam said. In 2020, she showed that the best way to search for black hole microlenses was to look for very long events. Only 1% of detectable microlensing events are likely to be from black holes, she said, so looking at all events would be like searching for a needle in a haystack. But, Lam calculated, about 40% of microlensing events that last more than 120 days are likely to be black holes.

“How long the brightening event lasts is a hint of how massive the foreground lens bending the light of the background star is,” Lam said. “Long events are more likely due to black holes. It’s not a guarantee, though, because the duration of the brightening episode not only depends on how massive the foreground lens is, but also on how fast the foreground lens and background star are moving relative to each other. However, by also getting measurements of the apparent position of the background star, we can confirm whether the foreground lens really is a black hole.”

According to Lu, the gravitational influence of OB110462 on the light of the background star was amazingly long. It took about one year for the star to brighten to its peak in 2011, then about a year to dim back to normal.

More data will distinguish black hole from neutron star

To confirm that OB110462 was caused by a super-compact object, Lu and Lam asked for more astrometric data from Hubble, some of which arrived last October. That new data showed that the change in position of the star as a result of the gravitational field of the lens is still observable 10 years after the event. Further Hubble observations of the microlens are tentatively scheduled for fall 2022.

Analysis of the new data confirmed that OB110462 was likely a black hole or neutron star.

Lu and Lam suspect that the differing conclusions of the two teams are due to the fact that the astrometric and photometric data give different measures of the relative motions of the foreground and background objects. The astrometric analysis also differs between the two teams. The UC Berkeley-led team argues that it is not yet possible to distinguish whether the object is a black hole or a neutron star, but they hope to resolve the discrepancy with more Hubble data and improved analysis in the future.

“As much as we would like to say it is definitively a black hole, we must report all allowed solutions. This includes both lower mass black holes and possibly even a neutron star,” Lu said.

“If you can’t believe the light curve, the brightness, then that says something important. If you don’t believe the position versus time, that tells you something important,” Lam said. “So, if one of them is wrong, we have to understand why. Or the other possibility is that what we measure in both data sets is correct, but our model is incorrect. The photometry and astrometry data arise from the same physical process, which means the brightness and position must be consistent with each other. So, there’s something missing there. “

Both teams also estimated the velocity of the super-compact lensing object. The Lu/Lam team found a relatively sedate speed, less than 30 kilometers per second. The STScI team found an unusually large velocity, 45 km/s, which it interpreted as the result of an extra kick that the purported black hole got from the supernova that generated it.

Lu interprets her team’s low velocity estimate as potentially supporting a new theory that black holes are not the result of supernovas — the reigning assumption today — but instead come from failed supernovas that don’t make a bright splash in the universe or give the resulting black hole a kick.

The work of Lu and Lam is supported by the National Science Foundation (1909641) and the National Aeronautics and Space Administration (NNG16PJ26C, NASA FINESST 80NSSC21K2043).

Journal

The Astrophysical Journal Letters

Method of Research

Observational study

Article Title

An isolated mass gap black hole or neutron star detected with astrometric microlensing

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Science

Astronomers May Have Detected a “Dark” Free-Floating Black Hole

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Artist’s illustration of a black hole.

Gravitational microlensing turns up

Yet black holes by their very nature can be very hard to detect, especially if they are isolated. After all, a black hole has such powerful gravity that light doesn’t escape, so we generally detect them by their gravitational influence on other objects or by radiation created by the surrounding matter they are devouring. Without nearby objects or accreting matter, there could be hundreds of millions of black holes throughout our galaxy that are essentially invisible to astronomers.

If, as astronomers believe, the death of large stars leaves behind black holes, there should be hundreds of millions of them scattered throughout the Milky Way galaxy. The problem is, isolated black holes are invisible.

Now, a team led by

The team, led by graduate student Casey Lam and Jessica Lu, a UC Berkeley associate professor of astronomy, estimates that the mass of the invisible compact object is between 1.6 and 4.4 times that of the sun. Because astronomers think that the leftover remnant of a dead star must be heavier than 2.2 solar masses in order to collapse to a black hole, the UC Berkeley researchers caution that the object could be a

Hubble Space Telescope image of a distant star that was brightened and distorted by an invisible but very compact and heavy object between it and Earth. The compact object — estimated by UC Berkeley astronomers to be between 1.6 and 4.4 times the mass of our sun — could be a free-floating black hole, one of perhaps 200 million in the Milky Way galaxy. Credit: Image courtesy of STScI/NASA/ESA

“This is the first free-floating black hole or neutron star discovered with gravitational microlensing,” Lu said. “With microlensing, we’re able to probe these lonely, compact objects and weigh them. I think we have opened a new window onto these dark objects, which can’t be seen any other way.”

Determining how many of these compact objects populate the Milky Way galaxy will help astronomers understand the evolution of stars — in particular, how they die — and of our galaxy, and perhaps reveal whether any of the unseen black holes are primordial black holes, which some cosmologists think were produced in large quantities during the

Because both microlensing surveys caught the same object, it has two names: MOA-2011-BLG-191 and OGLE-2011-BLG-0462, or OB110462, for short.

While surveys like these discover about 2,000 stars brightened by microlensing each year in the Milky Way galaxy, the addition of astrometric data is what allowed the two teams to determine the mass of the compact object and its distance from Earth. The UC Berkeley-led team estimated that it lies between 2,280 and 6,260 light years (700-1920 parsecs) away, in the direction of the center of the Milky Way Galaxy and near the large bulge that surrounds the galaxy’s central massive black hole.

The STScI group estimated that it lies about 5,153 light years (1,580 parsecs) away.

Looking for a needle in a haystack

Lu and Lam first became interested in the object in 2020 after the STScI team tentatively concluded that five microlensing events observed by Hubble — all of which lasted for more than 100 days, and thus could have been black holes — might not be caused by compact objects after all.

Lu, who has been looking for free-floating black holes since 2008, thought the data would help her better estimate their abundance in the galaxy, which has been roughly estimated at between 10 million and 1 billion. To date, star-sized black holes have been found only as part of binary star systems. Black holes in binaries are seen either in X-rays, produced when material from the star falls onto the black hole, or by recent gravitational wave detectors, which are sensitive to mergers of two or more black holes. But these events are rare.

“Casey and I saw the data and we got really interested. We said, ‘Wow, no black holes. That’s amazing,’ even though there should have been,” Lu said. “And so, we started looking at the data. If there were really no black holes in the data, then this wouldn’t match our model for how many black holes there should be in the Milky Way. Something would have to change in our understanding of black holes — either their number or how fast they move or their masses.”

When Lam analyzed the photometry and astrometry for the five microlensing events, she was surprised that one, OB110462, had the characteristics of a compact object: The lensing object seemed dark, and thus not a star; the stellar brightening lasted a long time, nearly 300 days; and the distortion of the background star’s position also was long-lasting.

The length of the lensing event was the main tipoff, Lam said. In 2020, she showed that the best way to search for black hole microlenses was to look for very long events. Only 1% of detectable microlensing events are likely to be from black holes, she said, so looking at all events would be like searching for a needle in a haystack. But, Lam calculated, about 40% of microlensing events that last more than 120 days are likely to be black holes.

“How long the brightening event lasts is a hint of how massive the foreground lens bending the light of the background star is,” Lam said. “Long events are more likely due to black holes. It’s not a guarantee, though, because the duration of the brightening episode not only depends on how massive the foreground lens is, but also on how fast the foreground lens and background star are moving relative to each other. However, by also getting measurements of the apparent position of the background star, we can confirm whether the foreground lens really is a black hole.”

According to Lu, the gravitational influence of OB110462 on the light of the background star was amazingly long. It took about one year for the star to brighten to its peak in 2011, then about a year to dim back to normal.

More data will distinguish black hole from neutron star

To confirm that OB110462 was caused by a super-compact object, Lu and Lam asked for more astrometric data from Hubble, some of which arrived last October. That new data showed that the change in position of the star as a result of the gravitational field of the lens is still observable 10 years after the event. Further Hubble observations of the microlens are tentatively scheduled for fall 2022.

Analysis of the new data confirmed that OB110462 was likely a black hole or neutron star.

Lu and Lam suspect that the differing conclusions of the two teams are due to the fact that the astrometric and photometric data give different measures of the relative motions of the foreground and background objects. The astrometric analysis also differs between the two teams. The UC Berkeley-led team argues that it is not yet possible to distinguish whether the object is a black hole or a neutron star, but they hope to resolve the discrepancy with more Hubble data and improved analysis in the future.

“As much as we would like to say it is definitively a black hole, we must report all allowed solutions. This includes both lower mass black holes and possibly even a neutron star,” Lu said.

“If you can’t believe the light curve, the brightness, then that says something important. If you don’t believe the position versus time, that tells you something important,” Lam said. “So, if one of them is wrong, we have to understand why. Or the other possibility is that what we measure in both data sets is correct, but our model is incorrect. The photometry and astrometry data arise from the same physical process, which means the brightness and position must be consistent with each other. So, there’s something missing there. ”

Both teams also estimated the velocity of the super-compact lensing object. The Lu/Lam team found a relatively sedate speed, less than 30 kilometers per second. The STScI team found an unusually large velocity, 45 km/s, which it interpreted as the result of an extra kick that the purported black hole got from the supernova that generated it.

Lu interprets her team’s low velocity estimate as potentially supporting a new theory that black holes are not the result of supernovas — the reigning assumption today — but instead come from failed supernovas that don’t make a bright splash in the universe or give the resulting black hole a kick.

Reference: “An isolated mass gap black hole or neutron star detected with astrometric microlensing” by Casey Y. Lam, Jessica R. Lu, Andrzej Udalski, Ian Bond, David P. Bennett, Jan Skowron, Przemek Mroz, Radek Poleski, Takahiro Sumi, Michal K. Szymanski, Szymon Kozlowski, Pawel Pietrukowicz, Igor Soszynski, Krzysztof Ulaczyk, Lukasz Wyrzykowski, Shota Miyazaki, Daisuke Suzuki, Naoki Koshimoto, Nicholas J. Rattenbury, Matthew W. Hosek Jr., Fumio Abe, Richard Barry, Aparna Bhattacharya, Akihiko Fukui, Hirosane Fujii, Yuki Hirao, Yoshitaka Itow, Rintaro Kirikawa, Iona Kondo, Yutaka Matsubara, Sho Matsumoto, Yasushi Muraki, Greg Olmschenk, Clement Ranc, Arisa Okamura, Yuki Satoh, Stela Ishitani Silva, Taiga Toda, Paul J. Tristram, Aikaterini Vandorou, Hibiki Yama, Natasha S. Abrams, Shrihan Agarwal, Sam Rose and Sean K. Terry, Accepted, The Astrophysical Journal Letters.
arXiv:2202.01903

The work of Lu and Lam is supported by the National Science Foundation (1909641) and the National Aeronautics and Space Administration (NNG16PJ26C, NASA FINESST 80NSSC21K2043).



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Strawberry supermoon will brighten skies Tuesday

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Move aside, baseball season. Never mind, beach season. For astronomy nerds, this summer marks supermoon season.

On Tuesday night, sky watchers will witness the first of three summer supermoons. A supermoon occurs when a full moon also happens to be at its closest distance to Earth in its orbit, known as perigee. Supermoons appear brighter and larger to us on Earth, providing spectacular nighttime gazing if skies are clear.

The moon will appear full starting Sunday night but will technically reach full illumination Tuesday at 7:52 a.m. Eastern. At around 7:24 p.m. Tuesday, the moon will be close enough to our Earth to be a supermoon. It will come within 222,238 miles of Earth (about 16,000 miles closer than its average distance) and could be about 7 percent larger and 15 percent brighter than a regular full moon.

While the criteria for a supermoon will be met Tuesday, the moon will appear full and bright in the night sky Monday through Wednesday. Check timeanddate.com for local moonrise and moonset times.

Five planets are aligned in night sky for first time in 18 years

This month’s full moon will also be the lowest full moon of the year, hovering only 23.3 degrees above the horizon Wednesday at 1:56 a.m. Eastern, according to NASA. Binoculars, a telescope or an excellent camera may help you spot craters and mountains on the lunar surface.

While the moon will appear larger and brighter, it will also accentuate low and high tides on Earth. Research suggests that decades of supermoons have been shown to heighten erosion risk on sandy beaches.

June’s full moon is commonly known as the “strawberry” moon, a name given by the Algonquin Native American tribe in the northeastern U.S. and eastern Canada and describing the short strawberry harvesting season in the region. European names include honey moon and rose moon, referring to honey harvesting and roses blooming during that time.

Here are the top astronomical sights for the rest of 2022

Although supermoons are not exceedingly rare, they do not occur every month. A full moon happens every 29.5 days, while the moon hits perigee every 27 days, overlapping occasionally. June’s supermoon follows another one in May. Next month’s full moon, known as the Buck Moon, will occur July 13 and will also be a supermoon. The moon will be within 222,089 miles of Earth and is the closest supermoon of the year. August’s supermoon will occur around the 12th.

The strawberry supermoon is only one exciting celestial event occurring in June. The summer solstice on June 21 marks the astronomical end of spring and start of summer. On June 24, before dawn, sky watchers can also see Earth’s five closest planetary neighbors in a row for the first time in 18 years.

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Space Telescope Hit by ‘Unavoidable Chance Event’

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(Newser)
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The massive mirror on the James Webb Space Telescope has been hit by what NASA calls an “unavoidable chance event”—a strike from a piece of space debris larger than they expected. NASA says one of the mirror’s segments was hit by a micrometeoroid, which it defines as a piece of debris smaller than a grain of sand, but the telescope is still performing above expectations, Live Science reports. The telescope reached its final orbit a million miles from Earth in January. NASA says the mirror has already had “four smaller measurable micrometeoroid strikes that were consistent with expectations,” but the one in late May was “larger than our degradation predictions assumed.”

“We always knew that Webb would have to weather the space environment, which includes harsh ultraviolet light and charged particles from the sun, cosmic rays from exotic sources in the galaxy, and occasional strikes by micrometeoroids within our solar system,” Paul Geithner, technical deputy project manager for NASA’s Goddard Space Flight Center, said in a statement. “We designed and built Webb with performance margin … to ensure it can perform its ambitious science mission even after many years in space.” NASA says the impact on the C3 section of the 18-piece mirror was larger than anything it could model while the telescope was still on Earth.

NASA says the mirror segments can be adjusted to lessen distortion caused by damage and to protect the mirror from events like meteor showers, CNN reports. “As a result of this impact, a specialized team of engineers has been formed to look at ways to mitigate the effects of further micrometeoroid hits of this scale,” NASA says. The agency says the Webb team is also learning more about the dust environment at the telescope’s current location, which will help future missions. (Read more James Webb Space Telescope stories.)

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Fossils of Europe’s largest meat-eating dinosaur found on Isle of Wight

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Step aside, T. Rex. 

Fossilized bones found on England’s Isle of Wight indicate there may have been an even bigger carnivorous king roaming pre-historic lands.

Paleontologists announced on Thursday that the remains of a meat-eating dinosaur may be larger than any other known in Europe and may be a cousin of the biggest carnivorous dinosaur species ever recorded, according to Reuters.

Parts of the skeleton of this dinosaur were dug up — including back, hip and tail bones and some limb fragments — they’ve been dated about 125 million years back during the Cretaceous Period.

SCIENTISTS CLAIM TO FIND DINOSAUR REMAINS FROM DAY OF ASTEROID STRIKE: REPORT

In an email exchange with Fox News Digital, University of Southampton paleobiologist Neil J. Gostling shared on Friday that these scattered remains lead him to believe that the massive beast measured “significantly” more than 33 feet long.

“This is a huge animal!” he exclaimed.

A diagram shows fossil remains of a meat-eating dinosaur dubbed the “White Rock spinosaurid,” dating from about 125 million years ago during the Cretaceous Period. This was unearthed on England’s Isle of Wight. (Barker et al/Handout via REUTERS)

“The spinosaurus that we described last year from the Wessex at the 127 million-year-old deposit … are animals which were roughly 8 to 9 m long. This animal is huge.”

“The size of the specimen is impressive,” University of Southampton doctoral student in paleontology Chris Barker told Reuters. 

“It is one of the biggest — and possibly the biggest — known land predators ever to stalk Europe.”

Experts concluded that the remains most likely belonged to a group of dinos called Spinosaurs, based on a pattern of small grooves on the top of the tail bone. 

T. REX MIGHT ACTUALLY BE THREE SEPARATE SPECIES: STUDY

This group includes the dinosaur Spinosaurus, which lived about 95 million years ago and has been considered the longest-measuring predator — at about 50 feet long.

Gostling revealed that this new dinosaur “very well could” be approaching Spinosaurus size.

Spinosaurs have a makeup comparable to crocodiles, with elongated skulls and plenty of cone-shaped teeth for chomping down on slippery, aquatic prey.

An artist’s illustration shows a large meat-eating dinosaur dubbed the “White Rock spinosaurid,” whose remains dating from about 125 million years ago during the Cretaceous Period were unearthed on England’s Isle of Wight, standing on a beach, surrounded by flying reptiles called pterosaurs. ​​
(Anthony Hutchings/Handout via REUTERS)

The newly found dinosaur has not yet been given a scientific name, since not all remains have been found — but paleontologists are calling it “White Rock spinosaurid” for the time being.

The name derives from the geological layer, the Cretaceous Vectis Formation, where the bones were uncovered. 

Experts believe this dinosaur is completely unique, not belonging to any other kind of species identified before it.

This layer is an “unusual” location, since coastal environments are not known to preserve fossils well, according to Gostling.

He added, “Maybe we shouldn’t be surprised that it is a spinosaur. Unlike other theropod dinosaurs, spinosaurus are known to have a closer relationship with water.”

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Experts believe this dinosaur is completely unique, not belonging to any other kind of species identified before it.

The analysis from Gostling and his team indicates the fossils might have specifically belonged to a Spinosaurine, which could mark the first Spinosaurine spinosaur in the British fossil record.

Among the meat-eating dinosaur family, also known as theropods, were some of the largest-known dinos on the continent — such as North America’s Tyrannosaurs Rex, measuring 42 feet, and Europe’s Torvosaurus, stretching about 33 feet.

A Tyrannosaurus Rex dinosaur fossil skeleton is displayed in a gallery at Christie’s auction house on Sept. 17, 2020, in New York City. (Spencer Platt/Getty Images)

The White Rock spinosaurid could be just as large as the T. Rex, Gostling told Reuters.

“Let’s hope more fossils turn up,” he said. 

“We would love a skull or teeth.”

The Isle of Wight has become a rich site for digging up dino bones.

The fossils were first spotted along Compton Bay on the Isle’s southwestern coast.

The Isle of Wight has become a rich site for digging up dino bones.

The bones were first discovered by Gostling’s colleague Dr. Jeremy Lockwood and dinosaur hunter Nick Chase — who died before the pandemic, thus missing the discovery’s public debut.

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“He would have been delighted and very pleased that Jeremy gave the material to me and Chris to look at, given what we have discovered the bones tell us,” Gostling said.

Reuters contributed reporting to this article. 

Angelica Stabile is a lifestyle writer for Fox News Digital. Follow her on Twitter at @atstabile.

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The Mars Perseverance Rover Has Picked Up a Hitchhiker — and NASA Says It’s a Long Way From Home

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A rock in the front left wheel of Perseverance on Sol 343, image was acquired on Feb. 6, 2022 (Sol 343).

NASA/JPL-Caltech

The Mars Perseverance rover has adopted a pet rock — or surprising hitchhiker — and has been taking care of it for four months.

The “unexpected traveling companion” first hopped a ride on the front left wheel of the rover in February, according to NASA, and has been riding around ever since. So far, it’s been transported more than 5.3 miles as the rover transmits images of the Red Planet to Earth.

“This rock isn’t doing any damage to the wheel, but throughout its (no doubt bumpy!) journey, it has clung on and made periodic appearances in our left Hazcam images,” NASA wrote in a statement, adding, “Perseverance’s pet rock has seen a lot on its travels… If this pet rock could talk, it might tell us about the changes it’s noticed as we [traveled] back north through the Octavia E. Butler landing site, and then west, passing the spectacular remains of the former extent of the delta, ‘Kodiak,’ on our journey to the western Jezero delta.”

The pet rock, may fall off the wheel at some point and will likely land among rocks that are very different.

“As one of our team members quipped this week, ‘we might confuse a future Mars geologist who finds it out of place!'” NASA wrote.

This isn’t the first time a rover picked up a rocky traveling companion, the agency noted. About 18 years ago, the Spirit rover collected a “potato-sized” rock that lodged itself into the rear right wheel and had to be dislodged. And the Curiosity rover occasionally picked up rocks as well.

But NASA noted the current Perseverance rock is “on its way to setting Mars hitch-hiking records!”

The Perseverance rover landed on Mars on Feb. 18, 2021, to “seek signs of ancient life and collect samples of rock and regolith (broken rock and soil) for possible return to Earth.” Since it arrived, it has been tweeting and sending images.

Later this month, the Grand Canyon will host a star party that kicks off with a Mars Perseverance presentation on June 18 to learn about the rover from someone who helped build it.

Alison Fox is a contributing writer for Travel + Leisure. When she’s not in New York City, she likes to spend her time at the beach or exploring new destinations and hopes to visit every country in the world. Follow her adventures on Instagram.



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The Length of a Day Oscillates Every 6 Years, And We May Finally Know Why

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How we think about our planet’s center may need to be seriously updated.

New evidence suggests that, instead of consistently rotating faster than Earth’s spin, the solid inner core oscillates – spinning first in one direction with respect to the surface far above, then the other, changing direction every six years.

 

This not only has implications for our understanding of the inner workings of our home world, it can also neatly explain a mystery that has perplexed scientists for some time: an oscillating variation in the length of Earth’s day, with a period of 5.8 years.

“From our findings, we can see the Earth’s surface shifts compared to its inner core, as people have asserted for 20 years,” said geophysicist John E. Vidale of the University of Southern California, Los Angeles (UCLA).

“However, our latest observations show that the inner core spun slightly slower from 1969-71 and then moved the other direction from 1971-74. We also note that the length of a day grew and shrank as would be predicted. The coincidence of those two observations makes oscillation the likely interpretation.”

Although our understanding of Earth’s core has developed a lot in recent decades, there’s still a lot we don’t know. We can’t just go there and take a gander at it; everything we know, we’ve gleaned from indirect observations, such as seismic waves propagating and bouncing through the entire planet.

 

But this is still a very effective tool. Scientists have been able to ascertain that Earth’s inner core is probably a hot, dense ball of solid iron, measuring roughly 2,440 kilometers (1,516 miles) across, a little bigger than the size of Pluto. Evidence also suggests that it demonstrates superrotation, rotating faster than Earth itself.

Researchers first detailed this phenomenon in 1996, with an estimated superrotation rate of 1 degree per year. Vidale and his colleague, Wei Wang, also of UCLA, later revised the rate down to 0.29 degrees per year, using data from underground nuclear tests conducted at the Russian Novaya Zemlya testing site in the 1970s.

In the new research, they went back in time, adding two tests conducted below Amchitka Island in 1971 and 1969. And that revealed something odd. The data suggested that, rather than superrotating, Earth’s inner core was subrotating – that is, spinning more slowly than Earth’s rotation, by about 0.1 degrees per year.

A diagram illustrating Vidale and Wang’s model. (Edward Sotelo/USC)

This, the researchers said, was consistent with oscillation. When in the full swing of its spin, the inner core superrotates, but then it slows down before speeding up again.

“The idea the inner core oscillates was a model that was out there, but the community has been split on whether it was viable,” Vidale said.

 

“We went into this expecting to see the same rotation direction and rate in the earlier pair of atomic tests, but instead we saw the opposite. We were quite surprised to find that it was moving in the other direction.”

The six-year periodicity of the oscillation neatly matches other oscillations for which we don’t have a confirmed explanation.

Earth’s days undergo time variations of plus or minus 0.2 seconds every six years or so, too, and Earth’s magnetic field also oscillates with a six-year period. In amplitude and phase, they match the periodicity of the model Vidale and Wang derived for the oscillations of Earth’s inner core.

This all means will require more data to unravel, which could be tricky. The facility that recorded the data from the nuclear tests, the US Air Force’s Large Aperture Seismic Array, closed in 1978, and underground nuclear testing is nowhere near as prolific as it used to be.

But further advances in sensor technology could mean that the detailed data needed to probe Earth’s inner core isn’t so far into the future; the results so far offer a tantalizing hint that Earth’s insides are a bit more complex than we knew.

“The inner core is not fixed – it’s moving under our feet, and it seems to [be] going back and forth a couple of kilometers every six years,” Vidale said.

“One of the questions we tried to answer is, does the inner core progressively move, or is it mostly locked compared to everything else in the long term? We’re trying to understand how the inner core formed and how it moves over time – this is an important step in better understanding this process.”

The research has been published in Science Advances.

 

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You can see 5 planets align this month in a rare astronomical conjunction

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Earthlings are able to see five of their closest planetary neighbors all lined up in a row this month.

Mercury, Venus, Mars, Jupiter and Saturn are aligned in their natural order across the morning sky in a rare conjunction.

In astronomical terms, conjunction is when two or more objects appear to line up in the sky.

Over the next week, Mercury will become easier to spot as it moves away from the sun. The planet is typically difficult to view, but Mercury will reach its greatest elongation, or farthest point from the sun, on June 16, making it easier to see, according to EarthSky.org.

And on June 24, about an hour before sunrise, skygazers can peep an extremely rare solar system extravaganza. The waning crescent moon will also be in position between Venus and Mars — taking the place of Earth in the planetary lineup.

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It’s the icing on the conjunction cupcake.

Sky & Telescope says the best time to see the planet conjunction on June24 is 45 minutes before sunrise looking East to South. (Sky & Telescope)

“Planets are often getting closer to each other and farther away from each other, but this is just a particularly fun order. It’s just coincidence,” Michelle Thaller, an astronomer at NASA told the Washington Post. “It’s just kind of this really sort of fun tour of the solar system that you can take for free.”

Over the next few months, the planets will appear to spread out across the morning sky. And by September, Venus and Saturn won’t be viewable for most morning sky observers, according to NASA.

All eight planets will never perfectly align due to our different orbits and tilts. Conjunctions of several planets happen fairly often, but the conjunction of five planets only happens about every 20 years.

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According to the Washington Post, the last time five planets aligned was in Dec. 2004 and the next time it will happen will be in 2040.

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