'Poppy seeds' and 'leopard spots' on Mars could hint at ancient microbial life
When you buy through links on our articles, Future and its syndication partners may earn a commission.
An arrowhead-shaped rock on Mars sporting features that may hint at ancient microbial activity on the Red Planet has left scientists puzzled.
NASA announced in July of last year that the rock, found in Mars' Jezero Crater by the agency's Perseverance rover, held some of the best evidence yet that ancient microbial life may have existed on the Red Planet billions of years ago, when it was significantly wetter than it is today. Earlier this week, scientists involved with the discovery presented their findings publicly for the first time this week at the Lunar and Planetary Science Conference in Texas, detailing the rock's chemical signatures and structures that continue to offer tantalizing hints of ancient Martian microbial life.
The fine-grained mudstone named Cheyava Falls, after the highest waterfall in Arizona's Grand Canyon, sits at the edge of an ancient river valley known as Neretva Vallis, which runs along the inner wall of the crater. The rock features spots of black, blue, or greenish hues, which the researchers have nicknamed "poppy seeds." Alongside these are dozens of dark-rimmed, millimeter-size splotches dubbed "leopard spots." Perseverance's instruments have revealed that several rocks hosting these two features are rich in iron, but that they vary in their oxidation states and redness — a telltale sign of activity by organic matter, which may have bleached the rocks of their red color.
"On Earth, reactions like these are commonly associated with microbially-driven organic matter respiration," Joel Hurowitz, the deputy principal investigator of the PIXL instrument located at the end of Perseverance's robotic arm, said at the conference.
Back in July, the discovery team had also noted the presence of calcium sulfate veins running through the rock, suggesting that water may have once flowed through it. While this and other features could point to non-biological processes, such as exposure to high temperatures from a volcanic event, ongoing analysis suggests the rock was never subjected to such heat or exposed to heat-related processes that would have caused it to recrystallize. "Everything seems to be consistent with low-temperature processes," Hurowitz said.
Scientists suspect the Neretva Vallis channel was carved out eons ago, by water gushing into the crater. One theory is that mud loaded with organic compounds was deposited into the valley, later cementing into the Cheyava Falls rock. Alternatively, a second water episode could have seeped into the rock after it had already formed, creating the features observed. "The rocks that we investigated appear to fill the Neretva Vallis channel," Hurowitz said.
There are no life-detection instruments onboard Perseverance, as its mission is to collect samples of scientific interest that will be returned to Earth for further scrutiny.
"As a community, we should feel compelled to do a whole lot of laboratory, field and modeling studies to try to investigate features like this in more detail," Hurowitz said. "And ultimately bring these samples back home so that we can reach a conclusion with regard to whether they were or were not formed by life."
However, details of the troubled Mars Sample Return effort remain uncertain after costs that ballooned to $11 billion led NASA to overhaul its approach and seek new ideas from its research centers, private industry and academia.
Former NASA administrator Bill Nelson announced earlier this year that the agency is leaving two options for the Trump administration to return to Earth 30 cigar-sized tubes containing bits of Mars that Perseverance has been collecting since 2021, including the Cheyava Falls sample. The two approaches differ in the way they would put hardware down on Mars, but either would require Congress to allocate $300 million to the mission for it to start launch proceedings by 2030 and return the samples between 2035 and 2039.
Related Stories:
— What makes Mars the 'Red' Planet? Scientists have some new ideas
— Perseverance Mars rover finds 'one-of-a-kind treasure' on Red Planet's Silver Mountain
— Ancient beach on Mars discovered by China's Mars rover: 'This strengthens the case for past habitability'
Scientists are eager to analyze the Cheyava Falls sample, as it could help answer one of humanity's most profound questions: Are we alone in the universe?
"The discovery of life beyond Earth is so profound, so paradigm-shifting, you have to get it right," Amy Williams, an astrobiologist at the University of Florida who's on the Perseverance science team, had told Space.com shortly after the discovery. "Once you cross that line, you can't come back."
Hashtags
Try Our AI Features
Explore what Daily8 AI can do for you:
Comments
No comments yet...
Related Articles
Yahoo
24 minutes ago
- Yahoo
See the moon shine with famous red star Antares in the southern sky on June 9
When you buy through links on our articles, Future and its syndication partners may earn a commission. The waxing gibbous moon will shine close to the red star Antares in the constellation Scorpius on the night of June 9. Stargazers in the U.S. will find the moon rising higher over the southeastern horizon after sunset on June 9, with Antares shining brightly around 4 degrees to the lower left of the lunar disk. For context, your little finger held at arms length accounts for roughly 1 degree in the night sky, while your index, middle and ring fingers together amount to around 5 degrees, according to NASA. Antares is also known as the "Heart of the Scorpion" thanks to its prominent position in the zodiacal constellation Scorpius, which itself contains a number of stunning deep sky objects, such as the Messier 4 globular cluster and the closest stellar nursery to Earth — Rho Ophiuchi. As a red supergiant, Antares boasts a diameter 700 times greater than our sun and is known to shine roughly 10,000 times brighter. It is expected to end its life in a dramatic supernova explosion when it runs out of fuel — an event that could happen anytime from tomorrow to a million years or so from now. The lunar disk will appear to close in on Antares as the night of June 9 progresses, with the red star eventually setting above the moon's upper left shoulder as the duo slip beneath the southwestern horizon in the predawn hours of June 10. Viewers based in a number of southern hemisphere countries, including Australia, Tasmania and Papua New Guinea, will see the moon slide directly in front of Antares, blocking its light in an event known as an '"occultation" starting at 4:47 a.m. EDT (0847 GMT), according to Stargazers hoping to capture the majesty of the lunar surface should check out our handy guide detailing how to photograph the moon, while those looking for a closer view of the cosmos should read our lists of the best telescopes and binoculars for exploring the night sky. Editor's Note: If you happen to capture a picture of the moon and Antares and want to share it with readers, then please send your photo(s), comments, and your name and location to spacephotos@
Yahoo
24 minutes ago
- Yahoo
Astronauts track huge dust clouds over Canada and US
When you buy through links on our articles, Future and its syndication partners may earn a commission. Preparations for the arrival of a visiting crew, the continued study of how humans adapt to the microgravity environment of space, the service of systems on board a docked cargo ship and the documentation of European landmarks from Earth orbit kept the seven astronauts and cosmonauts on the International Space Station (ISS) busy this week (June 2 through June 6), the sixth week of Expedition 73. "I noticed smoke over the Northern U.S. and Canada a few days ago, and it took me a little while to understand what it was. From our perspective, it almost looks like a differently colored cloud formation," flight engineer Nichole Ayers, a NASA astronaut, wrote on X on June 3 after spotting the smoke from wildfires in Canada that has caused evacuations in thee provinces and affected the air quality across several U.S. states. "The brown hue to the clouds and the fact that they overlapped the white clouds caught my eye. I've been trying to capture it daily to aid in understanding the smoke movement. I hope everyone stays safe!" Ayers wrote. Among the research that was conducted aboard the space station this week was: Bio-Monitor — For two days this week, NASA astronaut Jonny Kim wore this Canadian instrument to assess if it can collect his health data while being comfortable to wear and not interfere with his other activities. Virtual — Russian cosmonaut Alexey Zubritskiy, assisted by Sergey Ryzhikov, donned a pair of VR goggles as part of a study into the vestibular system's ability in microgravity to visually track movement while also keeping a sense of balance. Drain Brain 2.0 — Expedition 73 commander Takuya Onishi of JAXA (the Japan Aerospace Exploration Agency) measured the blood flow from his brain to his heart using electrodes from this rapid screening tool, which could help prevent and diagnose blood clots while in space. Elvis — Ayers worked with the Extant Life Volumetric Imaging System, a 3D microscope kept in JAXA's Kino laboratory, which she used to observe deep-sea bacteria samples. The demo could lead to using a similar device to identify possible infectious organisms in water supplies both in space and on Earth. Zubritskiy also spent a couple of days this week documenting Eastern European landmarks while fellow cosmonaut Kirill Peskov took photos of the Volga River and Aral Sea to visually assess the aftermaths of both natural and human-caused disasters. The crew also devoted time to maintaining the space station's systems, including: BEAM — Ayers and fellow NASA astronaut Anne McClain moved hardware into stowage aboard the Bigelow Expandable Activity Module, which serves as a "float-in" closet for the station since being installed and inflated in 2016. Spaceborne Computer-2 — Kim replaced a processor cartridge for this commercial off-the-shelf computer, which is being assessed for its ability to facilitate research analysis without the need for Earth-based support. PCBA — McClain updated the firmware for the Portable Clinical Blood Analyzer, a handheld unit that is used to quickly test blood samples for numerous research studies conducted on the ISS. AstroPi — Kim also relocated this computer-controlled camera from a window inside the Unity module to a different window inside the European Space Agency's (ESA) Columbus module. Students remotely use a pair of these cameras for engineering and science projects. Ryzhikov also cleaned out a heater fan and filled an oxygen generator tank in the Progress MS-29 (90P) cargo spacecraft as well as assisted Zubritskiy in the work to service a neutron radiation detector in the Russian segment of the space station. In addition to the work detailed above, McClain worked on SoFIE-MIST. "SoFIE-MIST stands for Solid Fuel Ignition and Extinction–Material Ignition and Suppression Test," she wrote in a June 6 X post. "MIST consists of a small-scale combustion wind tunnel, cylindrical fuel sample, an igniter, radiant heaters, and instrumentation. By varying parameters like air flow speed, oxygen concentration, pressure, and level of external radiation, then viewing the resultant flame produced on the sample, we can better characterize early behavior of fire. This helps us choose better materials for use in space, and it helps determine the best methods of extinguishing fires in space." "This week, I changed out the fuel samples and igniter for the next science run." The Expedition 73 crew's activities this week also included preparing for the arrival of short-term visitors: Axiom Space's fourth commercial mission to the International Space Station is scheduled to arrive aboard a SpaceX Dragon spacecraft on Wednesday (June 11), assuming an on-time launch the day prior. Former NASA astronaut Peggy Whitson will lead the Ax-4 crew, which includes pilot Shubhanshu Shukla of India and mission specialists Sławosz Uznański-Wiśniewski of Poland (and ESA) and Tibor Kapu of Hungary. The station crew reviewed the Ax-4 plan with mission managers on the ground while McClain and Ayers, who are assigned to oversee the Dragon's approach from inside the station, went over the docking procedures. The two used a computer to review the situations they could encounter when the Dragon nears the orbiting complex. Onishi readied the tablet computers that will be used by Whitson, Shukla, Uznański-Wiśniewski and Kapu during their two-week science research mission. As of Friday (June 6), there are 7 people aboard the International Space Station: commander Takuya Onishi of JAXA, Anne McClain, Nichole Ayers and Jonny Kim of NASA and Kirill Peskov, Sergey Ryzhikov and Alexey Zubritsky of Roscosmos, all flight engineers. There are two docked crew spacecraft: SpaceX's Dragon "Endurance" attached to the forward port of the Harmony module, and Roscosmos' Soyuz MS-27 attached to the Earth-facing port of the Prichal node. There are also two docked cargo spacecraft: Rosocmos' Progess MS-29 (90P) attached to the space-facing port of the Poisk module and Progress MS-30 (91P) attached to the aft port of the Zvezda service module. As of Friday, the space station has been continuously crewed for 24 years, 7 months and 5 days.
Yahoo
24 minutes ago
- Yahoo
HIV/AIDS: Facts about the viral infection that attacks the immune system
When you buy through links on our articles, Future and its syndication partners may earn a commission. QUICK FACTS ABOUT HIV What it is: A lifelong viral infection that weakens the immune system, if left untreated Prevention methods: Taking preventive medicines called PrEP, using condoms, and avoiding needle sharing Treatments: Medicines called antiretroviral therapy (ART) Human immunodeficiency virus (HIV) is a germ that causes a lifelong infection that slowly weakens the immune system. Though the infection is lifelong, medicines can keep the virus in check and help people reach lifespans of near-normal length. However, when people don't have access to those medicines, HIV infections progress to an advanced stage called acquired immunodeficiency syndrome (AIDS), which is fatal within about three years if not treated. When a person has AIDS, most of their key, disease-fighting immune cells are lost. This loss of immune protection leaves the person vulnerable to deadly infections and cancers. Although an HIV diagnosis was once a death sentence, scientists have developed treatments that suppress the virus and enable people to live long lives without transmitting the disease to others. Additionally, there are now effective preventive medications that can dramatically reduce the risk of getting HIV in the first place. There is not yet a widespread cure for HIV/AIDS, although a handful of people have been cured of the infection or are in long-term remission thanks to special stem-cell transplants, specially cell transplants from people who have genes that make them resistant to the virus. Scientists are exploring potential avenues for a cure, which could someday mean that people who contract HIV could be rid of the infection rather than having to take medication for life to manage the disease. HIV/AIDS remains a major public health threat worldwide, with an estimated 39.9 million people living with the disease at the end of 2023. Around 630,000 people died from illnesses related to AIDS the same year; by weakening the immune system, AIDS opens the door to these fatal diseases. HIV can spread through contact with an infected person's bodily fluids, although it's important to note that not all bodily fluids can transmit the virus. Bodily fluids that can spread HIV include blood, semen, preseminal fluid, vaginal secretions, breastmilk and rectal discharge (liquid from the anus that's not blood or stool). HIV is not transmitted through saliva, sweat or tears. It's also not spread through the air or through casual contact, such as hugging, shaking hands or sharing food. For transmission to occur, the bodily fluids containing HIV must come into contact with mucous membranes — tissues that line cavities in the body, like the vagina, anus or mouth. The fluids can also transmit HIV when they come into contact with cuts or sores, or when they're introduced to the bloodstream via contaminated needles, for instance. Most people who contract HIV get it through unprotected anal or vaginal sex — meaning sex without a condom or without HIV-preventing medications. People can also contract the virus by sharing the equipment used to inject drugs, such as needles or syringes. Babies can get HIV in the womb, during childbirth or from breastfeeding, if their mother has HIV. People living with HIV who take medicines called ART can suppress the virus to the point that it can't spread via sex. These "virally suppressed" people also have a much lower chance of transmitting HIV to their kids via pregnancy, childbirth or breastfeeding. They are also less likely to spread the virus via shared injection equipment, although experts aren't sure exactly how much the risk is reduced. The symptoms of HIV vary depending on how far the disease has progressed. The virus can spread from one person to another at any stage of the infection, unless the infected person is taking ART and has reached "viral suppression" (see glossary). The initial stage is called "acute HIV infection." Within two to four weeks of contracting the virus, many people develop a flu-like illness involving symptoms like fever, headache, rash and sore throat. These symptoms can last from a few days to a few weeks. Some people have no symptoms at this stage, however. The viral load, or amount of HIV in the blood, at this stage is very high. The second stage of the disease is "chronic HIV infection," during which the virus continues to multiply but at a slower speed than during acute infection. This stage is also called "clinical latency" or "asymptomatic HIV infection," as many people don't feel sick during it. People can remain in this stage of the disease for 10 to 15 years, though some pass through it more quickly. As the virus multiplies, levels of an important type of immune cell — CD4 T lymphocytes — decline. Without treatment, the disease will eventually enter its most advanced stage: AIDS. This can come with a wide range of symptoms, including rapid weight loss; recurring fever; night sweats; extreme tiredness; prolonged swelling of the lymph nodes; diarrhea; sores of the mouth, anus or genitals; and blotches on or under the skin or inside the mouth, nose or eyelids. It can also trigger neurological problems, like memory loss. AIDS raises the risk of severe bacterial infections and cancers, including lymphomas and Kaposi's sarcoma. It can also worsen viral infections, such as hepatitis B and mpox. Without any treatment, people with AIDS typically survive about three years. HIV and AIDS are related, in that AIDS is the most advanced stage of an HIV infection, and therefore, the HIV virus causes both conditions. AIDS can also be called a "stage 3 HIV infection." AIDS is defined in part by a very low CD4 count of fewer than 200 CD4 cells per cubic millimeter (mm3) of blood. Generally speaking, the CD4 counts of healthy teens and adults are around 500 to 1,200 cells/mm3. Anything below 500 cells/mm3 is considered low, and 200 cells/mm3 marks the threshold for an AIDS diagnosis. Doctors also diagnose AIDS by considering a patient's history of "AIDS-defining illnesses." These are medical conditions often seen in people with AIDS because their immune systems can't fight the illnesses off. They include "opportunistic" infections — those caused by germs that wouldn't necessarily harm a person with a well-functioning immune system. Such infections include a fungal infection called extrapulmonary cryptococcosis, recurrent blood infections with Salmonella bacteria, the parasitic infection toxoplasmosis, and lower respiratory infections caused by the herpes simplex virus. The bacterial disease tuberculosis poses a major risk to people with AIDS, and it is currently the leading cause of death for people living with HIV/AIDS worldwide. AIDS-defining illnesses also include cancers such as Kaposi's sarcoma, Burkitt's lymphoma and invasive cervical cancer. Others include HIV encephalopathy, which affects brain function, and HIV wasting syndrome, which causes extreme weight loss and weakness. Complications of AIDS-defining illnesses raise the risk of death, but the degree of risk varies among diseases. At all three stages of the infection, HIV is treated with antiretroviral therapy (ART) — combinations of medications that drive down the amount of HIV in the blood. Different ART drugs work in different ways to keep the amount of virus, or viral load, in check. They are available as daily pills or as shots given periodically throughout the year, depending on the person's treatment plan. It's key for patients to take their medication as prescribed, because missing pills or shots can open the door for the virus to multiply, as well as develop drug resistance, which causes the medication to work less well. ART medications can also interact with other drugs and carry some risk of serious side effects, so patients work with their medical providers to figure out which drug combination is best for them. The goal of ART is "viral suppression," which describes when a person's viral load falls low enough that there are 200 or fewer copies of the virus's genetic material per milliliter (mL) of blood. Historically, tests weren't sensitive enough to detect levels of HIV below that threshold, so doctors called this level "undetectable." Studies also found that people who reach viral suppression can't transmit the virus via sex; have a lower chance of spreading the virus through pregnancy, childbirth or breastfeeding; and likely have a lower chance of spreading it through needle sharing. This is why the slogan "undetectable equals untransmittable," or "U = U," was coined. Nowadays, some tests for HIV are extremely sensitive, so they can detect viral loads significantly below 200 copies/mL. However, experts emphasize that 200 copies/mL is still the critical threshold at which transmission risk becomes extremely low. If a person with HIV/AIDS develops another medical condition, such as an AIDS-defining illness, the individual would receive treatment for that condition in addition to their ART regimen. There is no widespread cure for HIV/AIDS. However, a handful of people have been cured of their HIV infections through stem cell transplants, and a few more are considered "potentially" cured via the same process. Stem cells can develop into different types of cells in the body. In certain cancers that affect blood cells, stem cell transplants can be used to replace the cells lost in the course of cancer treatments such as chemotherapy. Each individual who has been cured of HIV also had one of these cancers, so their doctors searched for stem cell donors who carry a rare gene that makes them resistant to HIV infection. By swapping in cells from an HIV-resistant individual, the procedure essentially locks the virus out of the patient's CD4 cells. There is one exception to this rule: A person known as the "Geneva patient" was potentially cured of HIV after a stem cell transplant, but the donor didn't have this special genetic resistance. It's unclear exactly why the man entered long-term remission from the infection after this procedure, but scientists are investigating. There have also been a couple of cases in which people's own immune systems somehow rallied against the virus and controlled it without treatment; these people are known as "elite controllers." Scientists hope to learn from both the stem cell recipients and from elite controllers to discover cures that could reach far more people with HIV/AIDS. Meanwhile, some researchers are exploring the use of gene-editing tools like CRISPR to cure the infection, while others are investigating the use of drugs and modified immune cells. Antiretroviral therapy (ART) – Combinations of medications that lower the amount of HIV in a person's blood. These drugs, given as pills or shots, prevent the viral infection from progressing to AIDS and dramatically lower a person's risk of complications and of transmitting the virus to others. Pre-exposure prophylaxis (PrEP) – Medicines that people at risk of being exposed to HIV take to prevent the infection. Viral load – The amount of HIV in a person's blood. This is measured in terms of the number of HIV RNA molecules — the virus's genetic material — found in a milliliter of blood. It's an important way to measure how well ART is working. Viral suppression – When a person's viral load falls to 200 copies/mL or lower. Viral suppression is the goal of ART, as it both lowers a person's likelihood of spreading the virus and extends their lifespan by preventing the infection from progressing to AIDS. CD4 T lymphocyte – A type of white blood cell that helps coordinate the actions of other immune cells to fight infections. HIV infects CD4 cells and uses them to multiply while the virus depletes the number of CD4 cells in the body. Image 1 of 4 In the 1980s and 1990s, groups organized "die-ins" to protest the lack of U.S. government attention to the ongoing HIV/AIDS crisis. Die-ins were also conducted to push for support for research to uncover effective treatments and, once treatments were discovered, to demand that those drugs be released to the public. The AIDS Coalition to Unleash Power — known as ACT UP — was a major force behind such protests and remains an active organization today. Image 2 of 4 Kaposi's sarcoma, an example of an AIDS-defining illness, characteristically causes big, purple patches or nodules to appear on the skin and mucous membranes. Image 3 of 4 The public health slogan "U = U," depicted on this sign, refers to the fact that people living with HIV who have undetectable viral loads cannot transmit the virus to others via sex. It stands for "undetectable = untransmittable." Image 4 of 4 The "Berlin patient," pictured here, was the first person cured of HIV via a stem cell transplant. His name was later revealed to be Timothy Ray Brown. Brown went on to launch a foundation under his name that was dedicated to fighting HIV/AIDS. We could end the AIDS epidemic in less than a decade. Here's how. In a 1st, HIV vaccine triggers rare and elusive antibodies in humans Nearly 3 million extra deaths by 2030 could result from HIV funding cuts, study suggests
