New lander version split in two, Perseverance Mars samples delayed until 2033

In order to bring the samples collected by the Perseverance rover back to Earth, NASA has plans to launch new landers, rovers and Mars ascent vehicles to connect the samples. But after some thought, NASA and ESA decided to revise the lander design to reduce the risk of failure and postpone the sample return mission to 2033.

NASA’s Perseverance rover is wandering around the Jezero crater and is expected to collect dozens of surface samples during its work period, waiting for the SRL lander (Sample Retrieval Lander) to take the Mars Ascent Vehicle (Mars Ascent Vehicle) in a few years. , MAV) arrived with another fetch rover, took these samples and handed them over to MAV, which then launched from the surface of Mars into Mars orbit, transferred the samples to the ERO orbiter, and finally brought the material back to Earth in 2031.

However, after further analysis, since a single lander needs a larger heat shield protection, the diameter is estimated to be 5.4 meters, which in turn requires a larger fairing to fit into the lander; in addition, whether the large lander can enter smoothly , descent and landing on Mars “unproven”, so NASA and ESA decided to change the design and split the SRL lander into two, one to carry the rover and the other to carry the MAV, so that the dual lander can be designed to carry the same The same system on Perseverance and Curiosity.

After the design change, the launch of the dual lander will be postponed to 2028, the launch of the ERO orbiter will be postponed from 2026 to 2027, and the Mars sample return mission will be postponed to 2033. NASA has yet to decide who will build the SRL2 lander that will carry the rover, which is expected to be announced in June.


The latest search results of the ninth planet, once again failed

After examining about 3,500 candidate sources tentatively identified as Planet Nine, astronomers announced the latest search results, still none of them are Planet Nine.

Since Caltech astronomers Konstantin Batygin and Michael Brown released a powerful statement in 2016, astronomers have believed that there is a planet called Planet Nine in the outer solar system. The celestial bodies are waiting to be discovered. The mass is estimated to be 5 to 10 times that of the earth and the distance from the sun is 200 to 800 AU. It affects more than 30 celestial bodies in the Kuiper belt to form extremely exaggerated, inclined and self-clustered orbits, but the ninth planet is also too large. Good at hiding, astronomers can only highly suspect but never find evidence.

At such a distance from the sun, the amount of sunlight reflected by celestial bodies is so rare that even telescopes like the Wide-field Infrared Survey Satellite (WISE), which hunt for infrared radiation, have been trying for years to find Planet Nine.

The team at the University of Oslo, Norway, who published the new study, chose to use the Atacama Large Millimeter and Submillimeter Array (ALMA), an array of radio telescopes typically used to search for the cosmic microwave background radiation, but its relatively high angle. The resolution and sensitivity are actually good for searching for Planet Nine, too.

In the past 6 years, the team has exhausted all means to search 87% of the sky in the southern hemisphere, looking for any faint sources that may be the ninth planet. Because the position and direction of the ninth planet’s movement are unknown, the researchers calculated 100 million possibilities, It brought about 3,500 candidate objects, but none were statistically significant, and none were confirmed, and everything was still empty.

The researchers admit that finding Planet 9 is really difficult, but they have selected 10 other signals for more research. Astronomers believe that if Planet 9 exists, there is a good chance of using the under-construction vibranium in the next five years. It was discovered by the Vera C. Rubin Observatory.

Severing ties with Russia, European Space Agency officially suspends cooperation on Exomars Mars mission

The ExoMars mission is a Mars exploration plan that the European Space Agency has cooperated with Russia’s Roscosmos for many years. It was finally finalized to launch a lander and a rover in September this year, but with Russia’s invasion of Ukraine, the European Space Agency officially announced that it will suspend continued cooperation with Russia, Start looking for other opportunities to launch probes.

In order to keep up with the exploration of alien planets, the European Space Agency also launched the ExoMars Mars mission, which was originally in cooperation with NASA, but the then-President Obama administration cut the Mars budget and withdrew from the program, which led to the ExoMars mission being destroyed for a time in 2012. Cancellation, it was the intervention of Russian aerospace company Roscosmos that helped fill the hole left by NASA’s departure.

Therefore, the European Space Agency and Roscosmos have cooperated with the ExoMars project, which consists of two sub-missions: the ExoMars Trace Gas Orbiter, which was first launched in 2016, to study the chemical composition of Mars; and the original plan for 2018. The Rosalind Franklin rover and Mars landing platform, which were launched but were delayed due to parachute problems and were finally scheduled for launch in September 2022, hope to keep up with the various exploration results of NASA and China on the surface of Mars.

However, in late February this year, Russia launched an invasion of Ukraine, which triggered a full-scale international censure. Western countries have resorted to economic and technical sanctions. For example, the European Organization for Nuclear Research (CERN), which has always remained politically neutral in the past, broke the principle and announced that Russian researchers are prohibited from continuing. Participating in the Large Hadron Collider experiment, the European Space Agency also stated earlier that the ExoMars rover would refuse to ride on the Russian proton launch vehicle, preferring to spend hundreds of millions of euros in addition to develop or buy a new Mars lander.

Now the European Space Agency has re-announced that the ExoMars mission has officially suspended cooperation with Russia, and will hold a committee meeting in the next few weeks to discuss how to continue promoting ExoMars without Russia’s participation. The possibility of launching in September this year has been approaching zero.

It is difficult to go to Mars. First, the earth and Mars orbit the sun at different speeds and distances. The longest distance from each other can reach 400 million kilometers, and the shortest distance is only 56 million kilometers. Flying to Mars during the closest distance can minimize rocket fuel and time consumption.

This period is therefore called the “Mars window period”. There will be an optimal time period for a probe to fly to Mars every 26 months, compressing the flight time to Mars to about 7 months.

The ExoMars mission missed this year’s schedule due to the Russian-Ukrainian war, and will have to be delayed until at least 2024 (and resume cooperation with Roscosmos) to launch again. If the partnership with Roscosmos has not been resumed, the European Space Agency has said that the ExoMars mission will continue to wait until 2026 or later, because some of the rover’s own instruments and heating devices are from Russia.

According to Foust, the agency is considering a partnership with NASA to develop a new rover.

NASA develops space suits after canceling female astronaut spacewalk due to “insufficient clothing”

Although the speed of technological development has been quite rapid, when exploring the vast universe, human beings can only “cross the river by feeling the stones”.

In March 2019, everyone was looking forward to the success of the “All-Women Astronaut Spacewalk” program announced earlier by NASA. Originally scheduled for March 29, astronauts Anne McClain and Christina Koch will perform an extravehicular mission to replace a second set of batteries for a different power channel in the same area of ​​the space station.

However, NASA announced plans to adjust the battery shortly after, replacing the batteries by male astronauts Nick Hague and Christina Koch. More “all-female astronaut spacewalks” didn’t happen, NASA said, in part because of a shortage of spacesuits on the space station.

More precisely, there is a shortage of spacesuits that fit the astronaut size. The space station only has a medium-sized spacesuit. Although the spacesuit can be replaced, it may take up to 12 hours. In order to avoid mission delays, only one female astronaut has suitable equipment to perform the mission.

In fact, Anne McClain has performed extravehicular missions before, but the space environment is different from the earth environment. When McClain performed the space mission, she found that the medium space suit only fit, and she and Koch could only be replaced by male astronauts to complete the mission. Therefore, the high-profile “all-female astronaut spacewalk” failed due to insufficient equipment.

It was this mission that exposed spacesuit design problems. At present, female astronauts only account for 11%. Under the limited budget, the common sizes of space suits are large or extra large, and there are not many suitable for female astronauts. NASA is developing the next generation of space suits, and one of the focuses is to hope to accommodate a more diverse astronaut.

To make the concept a reality, NASA funds related projects through the NIAC (Innovative Advanced Concepts) program. Bonnie Dunbar “creates custom high-performance spacesuits for exploring Mars” is one of them. Aerospace engineering professor Dunbar, a former astronaut, envisions using digital analysis components, from digital scanning to digital design/analysis to robotic fabrication, as well as 3D printing.

If this hypothesis materializes, extravehicular activity (EVA) space suits can be rapidly designed and manufactured, and can be used by crew members in any gravity environment. And while in space, astronauts can also make or repair on-site. NASA’s vision for the NIAC program is that astronauts walk into a body scanner and in a few hours will be able to walk on Mars in space suits. I really hope that day comes soon.

The black hole closest to Earth does not exist, it is actually a binary star system

In 2020, scientists announced the discovery of the black hole closest to the earth so far, a three-body system HR 6819 composed of 1,120 light-years away and two other bright stars, but follow-up observations pointed out that black holes do not exist, and HR 6819 is only composed of 2 stars binary system. Higher-resolution observations now show that there is indeed no black hole in the HR 6819 system, but two stars that are in the “stellar blood-sucking” stage orbiting at close range.

The year before last, when astronomers used the FEROS spectrometer on the MPG/ESO telescope at La Silla Observatory in Chile to conduct an in-depth study of the HR 6819 binary system in the existing database, they found that the system may be a triple star with a black hole. Metasystem, in which two stars revolve around each other in the form of binary stars, and the black hole orbits the pair of stars in a distant place, with a revolution period of about 40 days, in which the mass of the black hole is about 4 times that of the sun.

However, a few months later, another team conducted a second analysis based on the same data and found that the HR 6819 system was actually just a binary star system, with both stars orbiting for 40 days and no black hole at the center.

To find out, the two teams decided to work together to collect new observations using the Very Large Telescope (VLT) and the Very Large Telescope Interferometer (VLTI), resulting in higher-resolution images from the VLT that showed the two stars were only a short distance away. At one-third the distance between Earth and the sun, there are no bright companion stars orbiting further out, and no black holes.

As for why astronomers misunderstood the existence of black holes in the system in the first place? The team believes the best explanation is that they captured a phenomenon shortly after one of the stars sucked up the atmosphere of the companion star, sometimes referred to as a “stellar blood-sucking” process, which is relatively difficult to detect during the stage of stellar evolution, and further study of HR 6819 will reveal Uncover how the stellar blood-feeding process affects the evolution of massive stars.

Although the “disappearing” black hole is disappointing, the current black hole closest to Earth may become the one 1,500 light-years away that forms a binary system with π1 Grus, but astronomers believe that one day they will discover the number of stars lurking in the Milky Way. Tens of millions, even hundreds of millions of small black holes.

Largest radio galaxy ever discovered, with jets extending 100 times larger than the Milky Way

Astronomers have discovered the largest known radio galaxy ever, stretching at least 16 million light-years in space, and in front of it, the Milky Way, which is about 200,000 light-years in diameter, suddenly becomes tiny.

Radio galaxies are galaxies that are very bright at radio wavelengths and contain supermassive black holes in their cores. When matter falls into the black hole, it releases energy from the center of the galaxy in two jets of ionized plasma, possibly active galactic nuclei or quasi-active galaxies. Stars, blazars, and jets spread over a long distance, and the tail ends will spread into huge lobes of radio waves. The Milky Way also has radio lobes, and what scientists have not yet been able to clearly explain is why some galactic jets can grow to surprising sizes, leading them to be called giant radio galaxies.

Leiden University in the Netherlands used the Low-Frequency Array (LOFAR) distributed in 52 locations in Europe to detect the Alcyoneus galaxy at a distance of about 3 billion light-years from the earth through interference technology. The central supermassive black hole ejected two huge jets, The tail end also spreads into radio lobes, which together extend the Alcyoneus galaxy an astonishing 16.3 million light-years, four times larger than the previous record holder: IC 1101, which stretched 3.9 million light-years.

But the Alcyoneus galaxy is a normal elliptical galaxy with half the total mass of the Milky Way (240 billion times the mass of the sun), and the central black hole is about 400 million times the mass of the sun. Compared with most radio galaxies, the proportion of the center of Alcyoneus is generally small. How it produces such a huge jet is still a mystery to scientists.

One possibility is that the environment around the Alcyoneus galaxy is less dense than normal, allowing the jets to expand on an unprecedented scale. Another explanation is that Alcyoneus galaxies reside on filaments of the cosmic web (the vast structures of gas and dark matter that connect vast numbers of galaxies in the universe), allowing jets to extend along the structures and unseen dark matter on the way.

The paper will be published in the journal Astronomy & Astrophysics.

New galaxy evolution model confirms that dark matter-free galaxies are not alien

In order to explain how to make the universe run smoothly, theories suggest that all galaxies should be filled with a large amount of dark matter. However, over the years, scientists have discovered several galaxies with almost no dark matter, which seriously challenges the rules of the universe. Fortunately, a group of teams recently identified how dark matter-free galaxies can survive in a universe that contains a lot of dark matter — the former has lost track of dark matter.

Although dark matter has always been invisible, there are many clues to guide the way. The first and earliest evidence is galaxies. Observational data show that the rotation speed of the outer side of the galaxy is faster than that expected by Newton’s gravity, indicating that there must be a huge amount of mass energy pulling the outer side of the galaxy to prevent the galaxy from falling apart. Since then, dark matter has gained a firm foothold and is difficult to separate from the galaxy. Models suggest that dark matter condenses into filaments and forms nodes at higher densities, which in turn attract visible matter to gather to form clusters of galaxies, which, because galaxies contain much dark matter, continue to merge to shape galaxy clusters today.

Therefore, it is difficult to understand that a galaxy does not contain dark matter.

However, in 2018, scientists encountered an extremely embarrassing moment: the discovery of a galaxy with almost no dark matter, called NGC 1052-DF2. Because NGC 1052-DF2 is located near a group of galaxies dominated by the large elliptical galaxy NGC 1052, the team suspected at the time that billions of years ago, the giant fledgling elliptical galaxy might have somehow caused NGC 1052-DF2 during its growth. Galaxies lack dark matter.

Another idea is that the galaxy NGC 1052-DF2 experienced a catastrophic event inside that wiped out all the gas and dark matter and prevented new stars from forming.

A year later, in 2019, another team discovered a second galaxy without dark matter, named NGC 1052-DF4 (DF4 for short), proving that NGC 1052-DF2 is not a special case, and there must be an unimaginable dark matter-free galaxy in the universe Galaxies are waiting to be excavated.

New galaxy evolution model unexpectedly confirms past inferences
Recently, the University of California, Irvine team originally wanted to model the evolution of galaxies, but the model unexpectedly produced 7 galaxies with almost no dark matter. The researchers then used the model to examine the evolution of these galaxies and found that at first, these galaxies had no dark matter. Dark matter galaxies are actually normal small galaxies, and dark matter also exists, but they are eventually stripped of dark matter due to mergers with larger nearby galaxies.

In short, these small galaxies were engulfed, but somehow reappeared on the other side with about half of the stars, but with all the gas and dark matter missing.

The theory confirms the team’s idea in 2018 that collisions between neighboring galaxies would trigger looting, leaving smaller galaxies with only a few stars and remnant dark matter left.

The University of California, Irvine team said that this also shows that the galaxies lacking dark matter should be more than the two discovered above, especially in the vicinity of massive galaxies. As many as 30% of the massive galaxies in the universe may have small galaxies without dark matter.

Astronomers are busy with new topics. The research paper was published in the journal Nature Astronomy.

The supermassive black hole of the M77 galaxy has always been blocked by dust in the past, and now the location is finally confirmed

At the center of the galaxy M77, some 47 million light-years from Earth, a supermassive black hole has finally been discovered hidden within a thick cloud of dust. Where the black hole hides in this dust cloud has been a mystery for decades, but scientists have now used detailed data from VLTI to measure the temperature at various points in the cloud to finally pinpoint the location of the supermassive black hole.

Active galactic nuclei (AGNs) are of various types, some emit radio waves and some don’t; some glow brightly in visible light, while others are softer, such as galaxy M77. Because there are so many subdivisions of appearance, astronomers introduced the AGN unified model, pointing out that although there are differences in active galactic nuclei, they all have the same basic structure: a supermassive black hole surrounded by a thick dust ring, all appearance differences in active galactic nuclei, It all depends on the different directions and angles from which we observe the black hole and the dust ring from the earth. If the dust ring is thick enough to block the black hole, the black hole can even be completely hidden under certain conditions.

Messier 77 (also known as M77, NGC 1068) is a barred spiral galaxy 47 million light-years from Earth and an active galaxy with an active galactic nucleus (AGN), but it is obscured by warm dust in the visible light band, and astronomical Questions remain about whether dust can completely hide a black hole, causing the AGN to be less bright than other AGNs in visible light.

Now thanks to the MATISSE instrument installed on the Very Large Telescope Interferometer (VLTI), the team of astronomer Gámez Rosas of Leiden University in the Netherlands has mapped the temperature change of the dust caused by the intense radiation of the black hole, not only finding the thick cosmic dust gas The ring also confirms the location of the supermassive black hole hidden in it, finally solving the problem of scientists for many years, and also providing important evidence to support the AGN unified model.

These findings may help determine the history of Sagittarius A*, the supermassive black hole at the center of the Milky Way, and analyze the interactions between active galactic nuclei and galaxies. The new paper was published in the journal Nature.

Unlike other planets, Saturn’s upper winds prove to provide ‘fuel’ to drive powerful auroras

Scientists have long wondered that some of Saturn’s auroras arise from cyclones in the atmosphere. After all, on Earth or other planets like Jupiter, auroras come from charged particles interacting with the magnetosphere. A team from the University of Leicester has recently discovered an unprecedented mechanism that suggests that strong winds in the upper reaches of Saturn’s north pole are responsible for fueling Saturn’s auroras.

The Pioneer 11 spacecraft first saw signs of Saturn’s auroras when it flew by Saturn in 1979; Voyager 1 and Voyager 2 flybys of Saturn in the early 1980s also provided observations of the giant magnetic bubble around Saturn, just like Earth , Saturn’s magnetosphere interacts with the solar wind to form the auroras.

The magnetosphere isn’t the only driving force behind Saturn’s auroras, however, and Saturn is a unique planet so far observed in that some of the auroras are produced by winds in Saturn’s own atmosphere.

When the Cassini probe set out to measure the overall rotational speed by measuring radio-emission pulses from Saturn’s atmosphere, it was astonished to find that Saturn’s rotational rate had changed over 20 years, and that Saturn’s rotational period would drift eerily north-south and at different speeds in different seasons. rotate. We determined that the internal rotation rate of Saturn must remain constant, so there must be other mechanisms outside affecting the observations.

So far, various theories trying to explain changes in Saturn’s magnetic field have surfaced, such as Saturn’s rings, the methane atmosphere of Titan, and the eruption of Enceladus’ volcanoes, etc., but none of the above seems to be correct.

New research by a team from the University of Leicester has detected winds in the planet’s upper atmosphere for the first time and provides evidence that these winds are what tug on Saturn’s magnetic field and provide the ‘fuel’ to produce the auroras. Dragging the planet’s magnetic field so that the latter keeps changing makes it impossible for scientists to measure the speed of Saturn’s rotation or to know how long Saturn’s day is (but then scientists figured out a way to measure Saturn’s rotation period using Saturn’s ring system).

The researchers believe that the system is driven by the energy of Saturn’s thermosphere, and the ionospheric wind speed falls between 0.3 and 3 kilometers per second, determining the origin of the radio pulse variation and dispelling our confusion about the variation of Saturn’s rotation speed.

The Milky Way’s First Wandering Black Hole May Be Here, Just 5,150 Light-years From Us

In the universe, there is a serious gap between the number of black holes that have been discovered and the expected number. One of the reasons is that black holes are low-key and no one can find them. Maybe they are lurking nearby, but we can’t see them. But recently, a team of astronomers appears to have detected, for the first time, a “wandering black hole” wandering alone in the Milky Way, just 5,150 light-years away.

Although black holes are extremely gravitational, they may be the darkest objects in the universe. Scientists usually have to know of black holes through other means, such as the hot accretion disk orbiting the black hole, the bright light released by the black hole when it devours the stars, and being affected by the black hole. Orbiting celestial bodies, or gravitational waves caused by collisions with other massive objects.

Although there are many indirect ways to find black holes, in fact, there is a huge gap between the number of black holes we have found and the predicted value of the model. For example, there should be at least 100 million stellar black holes in the Milky Way (a star with a mass of more than 20 solar masses will die when it dies. A recent study also predicted that there are at least 40,000,000,000,000,000,000 stellar black holes in the universe. This number does not include supermassive black holes and theoretical intermediate-mass black holes.

Astronomers have long predicted that stellar black holes should be ubiquitous, but largely invisible because they don’t interact with others. But these “isolated” black holes can manifest themselves in one way – the gravitational lensing effect: when a black hole passes in front of a background light source, the strong gravity slightly distorts distant light to brighten and “bend” it. For decades, astronomers have Close attention has been paid to gravitational lensing events that cannot be explained by visible objects such as stars and galaxy clusters, which may indicate the existence of an invisible black hole there.

The more massive the object that causes gravitational lensing, the longer it takes to brighten the background light source, and if the object is a black hole, the microlensing event lasts longer and doesn’t emit any detectable light itself .

Now, for the first time, astronomers may have solid evidence of a wandering black hole.

Combining 6 years of observational data from Hubble and ground-based telescopes, scientists discovered a 270-day microlensing event, called MOA-2011-BLG-191/OGLE-2011-BLG-0462, estimated to be a mass of about the Sun 7.1 times the size of a stellar black hole and moving at about 45 kilometers per second, much faster than the stars around this region of the Milky Way.

The research team estimates that the black hole may have been born about 100 million years ago, but there is no clear path to trace the origin of the black hole. In the future, the Roman Space Telescope (formerly the WFIRST Wide-Field Infrared Survey Telescope) and the Vera C. Rubin Observatory (formerly the LSST Large Synthetic Survey Telescope) in Chile may help find more strays Stellar black hole.