NASA's Perseverance rover is reveling in a scientific bonanza on Mars after finding a diverse array of rocks that are providing eager scientists a glimpse into the planet's ancient history.
The Perseverance rover is currently exploring Mars hills, boulders and rocky outcrops along the rim of Jezero Crater, a dry, bowl-shaped depression north of the Martian equator that likely held a lake billions of years ago. Since reaching the crater's western rim in December of last year, the rover has focused its attention on the layered terrain of a tall slope called Witch Hazel Hill, which could hold clues to a period when Mars had a vastly different climate. In the past few months alone, the car-sized Perseverance has collected samples of five rocks, performed detailed analysis on seven others, and zapped an additional 83 with its laser for remote study — the robotic explorer's fastest pace of scientific data collection since it landed on the Red Planet four years ago, NASA says.
The crater's western rim is proving to be a scientific goldmine because it contains lots of fragmented, once-molten rocks that had been blasted from deep beneath the surface billions of years ago by meteor impacts, possibly including the impact that created Jezero Crater itself, according to the statement.
Of key interest to astronomers is Perseverance's first crater rim sample, named Silver Mountain, which is a "one-of-a-kind treasure" likely dating back at least 3.9 billion years to the Noachian age — an early Martian period of heavy bombardment that shaped the planet's cratered landscape we see today, NASA .
NASA's Perseverance rover is reveling in a scientific bonanza on Mars after finding a diverse array of rocks that are providing eager scientists a glimpse into the planet's ancient history.
The Perseverance rover is currently exploring Mars hills, boulders and rocky outcrops along the rim of Jezero Crater, a dry, bowl-shaped depression north of the Martian equator that likely held a lake billions of years ago. Since reaching the crater's western rim in December of last year, the rover has focused its attention on the layered terrain of a tall slope called Witch Hazel Hill, which could hold clues to a period when Mars had a vastly different climate. In the past few months alone, the car-sized Perseverance has collected samples of five rocks, performed detailed analysis on seven others, and zapped an additional 83 with its laser for remote study — the robotic explorer's fastest pace of scientific data collection since it landed on the Red Planet four years ago, NASA says.
The crater's western rim is proving to be a scientific goldmine because it contains lots of fragmented, once-molten rocks that had been blasted from deep beneath the surface billions of years ago by meteor impacts, possibly including the impact that created Jezero Crater itself, according to the statement.
Of key interest to astronomers is Perseverance's first crater rim sample, named Silver Mountain, which is a "one-of-a-kind treasure" likely dating back at least 3.9 billion years to the Noachian age — an early Martian period of heavy bombardment that shaped the planet's cratered landscape we see today, NASA .
Life this planet has signatures of an active oceanic plant based biosphere.
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1. Introduction 2. Observations and Data Reduction 3. Atmospheric Retrieval 4. Summary and Discussion We report a mid-infrared transmission spectrum of the candidate hycean world K2-18 b observed with the JWST MIRI LRS instrument, the first for a habitable-zone sub-Neptune. The spectrum shows multiple spectral features between ~6 and 11 µm that are best explained by a combination of DMDS and DMS in the atmosphere, both molecules uniquely produced by life on Earth and predicted as promising biosignatures in habitable exoplanets (S. D. Domagal-Goldman et al. 2011; S. Seager et al. 2013b; D. C. Catling et al. 2018; E. W. Schwieterman et al. 2018; S.-M. Tsai et al. 2024). We detect the combination of DMDS and/or DMS at a significance of 2.9s–3.2s across the canonical retrievals reported in this work. In the absence of DMDS, the spectral features can also be explained to a large extent by DMS, and vice versa, due to degeneracy between the spectral features of DMS and DMDS in the mid-infrared. In retrievals considering only one of the two molecules (DMS or DMDS) in the canonical model, DMS is retrieved at 2.9s–3.0s significance and DMDS is retrieved at 3.0s–3.2s significance.
The observations provide limited constraints on other atmospheric properties. In the absence of DMS and DMDS, no significant detections or abundance constraints are obtained on any of the remaining molecules considered in the retrievals. The strong DMDS and/or DMS features dominate over potential molecular contributions from any other species in this wavelength range. We find high abundances of DMDS and/or DMS with volume mixing ratios of ???????10-5 (10 ppmv) within the 1s uncertainties and a MIRI photospheric temperature of K at 1 mbar for the canonical retrieval. The DMS abundance and photospheric temperature are consistent with but somewhat higher than those derived from previous NIRISS and NIRSpec observations in the 1–5 µm region (N. Madhusudhan et al. 2023b). On the other hand, both the retrieved mixing ratios and temperature are strongly dependent on the available cross sections of DMDS and DMS that are obtained for an Earth-like atmosphere at what follows, we discuss the implications and future directions.
4.1. Biosignature on a Hycean World Our findings provide new independent evidence for the possibility of a biosphere on K2-18 b.
Life this planet has signatures of an active oceanic plant based biosphere.
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Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
1. Introduction 2. Observations and Data Reduction 3. Atmospheric Retrieval 4. Summary and Discussion We report a mid-infrared transmission spectrum of the candidate hycean world K2-18 b observed with the JWST MIRI LRS instrument, the first for a habitable-zone sub-Neptune. The spectrum shows multiple spectral features between ~6 and 11 µm that are best explained by a combination of DMDS and DMS in the atmosphere, both molecules uniquely produced by life on Earth and predicted as promising biosignatures in habitable exoplanets (S. D. Domagal-Goldman et al. 2011; S. Seager et al. 2013b; D. C. Catling et al. 2018; E. W. Schwieterman et al. 2018; S.-M. Tsai et al. 2024). We detect the combination of DMDS and/or DMS at a significance of 2.9s–3.2s across the canonical retrievals reported in this work. In the absence of DMDS, the spectral features can also be explained to a large extent by DMS, and vice versa, due to degeneracy between the spectral features of DMS and DMDS in the mid-infrared. In retrievals considering only one of the two molecules (DMS or DMDS) in the canonical model, DMS is retrieved at 2.9s–3.0s significance and DMDS is retrieved at 3.0s–3.2s significance.
The observations provide limited constraints on other atmospheric properties. In the absence of DMS and DMDS, no significant detections or abundance constraints are obtained on any of the remaining molecules considered in the retrievals. The strong DMDS and/or DMS features dominate over potential molecular contributions from any other species in this wavelength range. We find high abundances of DMDS and/or DMS with volume mixing ratios of ???????10-5 (10 ppmv) within the 1s uncertainties and a MIRI photospheric temperature of K at 1 mbar for the canonical retrieval. The DMS abundance and photospheric temperature are consistent with but somewhat higher than those derived from previous NIRISS and NIRSpec observations in the 1–5 µm region (N. Madhusudhan et al. 2023b). On the other hand, both the retrieved mixing ratios and temperature are strongly dependent on the available cross sections of DMDS and DMS that are obtained for an Earth-like atmosphere at what follows, we discuss the implications and future directions.
4.1. Biosignature on a Hycean World Our findings provide new independent evidence for the possibility of a biosphere on K2-18 b.
Astrobiologist is an extraterrestrial life expert.
It is a ketch 22 how can there be an extraterrestrial life expert if there wasn't extraterrestrial life however....
If
K2-18b is in fact a Hycean world, the strength of this dimethyl sulfide could indicate there’s life on an exotic ocean world—and that the ocean dominating that planet is absolutely teeming with, say, marine algae.
While algae isn’t little green men, the detection of any kind of life elsewhere in the cosmos would fundamentally change our understanding of our place in the universe.
According to the study, the detection sits at a confidence level of what scientists refer to as 3s, meaning that there is about a 0.3 percent chance that this signal (even after all the filtering work the team did) is a fluke or background fluctuation, and not a real detection. In astrophysics, something is considered a discovery when the detection is made with a confidence level of 5s, meaning that there is only about a 0.00006 percent chance the detection isn’t real.
At 3s—especially regarding a claim as monumental as “we found a signal of alien life”—scientists (including the ones who made the discovery) are still proceeding with extreme caution; no one is saying, “this is aliens!” Astrobiologist Edward Schwieterman told NPR that the detection still seems “tentative” to him, and he wouldn’t be surprised “if the signal went away” when other researchers get their hands on the data collected by Madhusudhan and his team.
Hycean worlds are a water ocean and hydrogen atmosphere. Plant life and algae produce the disulfides.
If we go back to Genesis God parted the sea and dry land appeared here. This would be a world where that hasn't happened yet.
Source popular mechanics.for this article.
Astrobiologist is an extraterrestrial life expert.
It is a ketch 22 how can there be an extraterrestrial life expert if there wasn't extraterrestrial life however....
If
K2-18b is in fact a Hycean world, the strength of this dimethyl sulfide could indicate there’s life on an exotic ocean world—and that the ocean dominating that planet is absolutely teeming with, say, marine algae.
While algae isn’t little green men, the detection of any kind of life elsewhere in the cosmos would fundamentally change our understanding of our place in the universe.
According to the study, the detection sits at a confidence level of what scientists refer to as 3s, meaning that there is about a 0.3 percent chance that this signal (even after all the filtering work the team did) is a fluke or background fluctuation, and not a real detection. In astrophysics, something is considered a discovery when the detection is made with a confidence level of 5s, meaning that there is only about a 0.00006 percent chance the detection isn’t real.
At 3s—especially regarding a claim as monumental as “we found a signal of alien life”—scientists (including the ones who made the discovery) are still proceeding with extreme caution; no one is saying, “this is aliens!” Astrobiologist Edward Schwieterman told NPR that the detection still seems “tentative” to him, and he wouldn’t be surprised “if the signal went away” when other researchers get their hands on the data collected by Madhusudhan and his team.
Hycean worlds are a water ocean and hydrogen atmosphere. Plant life and algae produce the disulfides.
If we go back to Genesis God parted the sea and dry land appeared here. This would be a world where that hasn't happened yet.
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