Lifeboat Foundation

The biggest buzz in ground-based astronomy these days is the soon to be completed Rubin Observatory and its forthcoming wide field Large Synoptic Sky Survey.

When the widefield optical Rubin Observatory comes online later this year, it will not only revolutionize astronomy, but the art of science data management as well.

The Space Force announced Friday that it has given Microsoft a contract to continue work on a simulated environment where guardians can train, test new capabilities and interact with digital copies of objects in orbit.

Under the $19.8 million, one-year contract from Space Systems Command (SSC), Microsoft will develop the Integrated, Immersive, Intelligent Environment (I3E) — an augmented reality space simulation powered by the company’s HoloLens headsets. The training tool is a successor to the service’s Immersive Digital Facility (IDF) prototype developed in 2023, according to a press release.

The contract period began Dec. 1, and the deal includes a reserved scope for an additional three years of work, per the release.

“The misperception of Neptune’s color, as well as the unusual color changes of Uranus, have bedeviled us for decades. This comprehensive study should finally put both issues to rest,” said Dr. Heidi Hammel.

In space, not everything is how it seems, and this might be the case with Uranus and Neptune, as a study scheduled to be published in February 2024 in the Monthly Notices of the Royal Astronomical Society examines how the colors of the two gas giants might be more similar that what NASA’s Voyager 2 spacecraft imaged in 1986 and 1989, respectively, as it flew past the gas giants during its mission. Originally, Voyager 2 imaged Uranus to exhibit a greenish-type color while Neptune appeared to be a strong blue, and this new study holds the potential to help scientists better understand how to estimate the true colors of planets throughout the cosmos.

“Although the familiar Voyager 2 images of Uranus were published in a form closer to ‘true’ color, those of Neptune were, in fact, stretched and enhanced, and therefore made artificially too blue,” said Dr. Patrick Irwin, who is a Professor of Planetary Physics at the University of Oxford and lead author of the study. “Even though the artificially-saturated color was known at the time amongst planetary scientists – and the images were released with captions explaining it – that distinction had become lost over time.”

Continue reading “Revealing the True Colors of Neptune and Uranus: A Breakthrough Study” »

First, we halved the deep methane abundance (model A), since we know the polar regions are methane-depleted, but found that although such a change produces changes in (I/F)₀ and k that reasonably approximate the shape of observed differences between the polar and equatorial regions in Fig. 12, the amplitude is not sufficiently large and is close to zero at blue wavelengths. Secondly, we tried halving the methane abundance and increasing the opacity of the Aerosol-2 layer, τ₂, by 1.0 (model B), from 4.6 to 5.6. Note that all opacities quoted here are at a reference wavelength of 800 nm. Here, we see an increase in the (I/F)₀ and k difference at green wavelengths, but a decrease at blue wavelengths. The reason for this is that the Aerosol-2 particles are retrieved to have increased imaginary refractive index at blue wavelengths (Irwin et al. 2022), which lowers the single-scattering albedo here. Hence, increasing the Aerosol-2 opacity reduces the reflectivity at blue wavelengths, rather than increasing it. How then can we match the observed differences between the polar and equatorial spectra of the 2002 HST/STIS data? In the study of James et al. (2023), noted earlier, it was found that the optimal solution was to not only increase the opacity of the particles in the Aerosol-2 layer, but also make them more reflective at wavelengths longer than 500 nm. We could have similarly adjusted the imaginary refractive index spectra, n_imag, of the Aerosol-2 particles (lower n_imag values increase the single-scattering albedo), but in a parallel analysis of VLT/MUSE observations of Neptune, Irwin et al. (2023b) found that the observed spectra of deep bright spots could be well approximated by adding a component of bright particles to the existing Aerosol-1 layer at ∼5 bar. We wondered whether a similar approach might be applicable here. Changes in the Aerosol-1 layer cannot account for the observed HST/STIS pole–equator differences, since this layer is only detectable in narrow wavelength bands of very low methane absorption, but in Fig. 12 it can be seen that if we add a unit opacity of conservatively scattering particles to the Aerosol-2 layer at 1–2 bar (with the same Gamma size distribution as the Aerosol-2 particles, with mean radius 0.6 μm and variance σ = 0.3) the (I/F)₀ and k difference increases at all wavelengths longer than ∼ 480 nm (model X), although not as much as the difference between polar and equatorial latitudes. However, if we add this additional opacity and simultaneously halve the methane abundance (Model C1) we find that the differences in the (I/F)₀ and k spectra agree moderately well with the observed pole–equator difference spectra at most wavelengths. What might be responsible for this extra component of bright particles in the Aerosol-2 layer will be discussed further, but it could indicate that more methane ice particles are present in the haze/methane-ice layer, or that more methane ice is condensed onto the haze Cloud Condensation Nuclei (CCN). Whatever the cause, it is clear that the spectral difference between the polar and equatorial regions seen by HST/STIS in 2002 is consistent with a reduction in methane abundance coupled with an increase in the reflectivity of the particles in the Aerosol-2 layer that could be caused by the addition of a conservatively scattering component.

Having surveyed the possible interpretations of the HST/STIS polar and equatorial spectra, we then tested these models against the seasonal photometric magnitude data. While the Lowell Observatory magnitude data accurately preserve the quantities that were measured, they are a less intuitive measure for interpreting the changes in Uranus’s reflectivity spectrum with atmospheric models. Hence, we converted the magnitudes to the mean disc-averaged reflectivities of Uranus, which also corrects out the solid-angle variations of Uranus’s disc size, noted earlier. This conversion was done using the procedures outlined in Appendix B. The resulting seasonal variations in disc-averaged reflectivity at the blue and green wavelengths of the Strömgren b and y filters are shown in Fig. 13. Here, it can be seen that the disc-averaged green reflectivity of Uranus changes from ∼0.47 to ∼0.

This article was originally published at The Conversation. The publication contributed the article to Space.com’s Expert Voices: Op-Ed & Insights.

In May 2020, some unusual rocks containing distinctive greenish crystals were found in the Erg Chech sand sea, a dune-filled region of the Sahara Desert in southern Algeria.

Jupiter’s largest moon, Ganymede, features a surprisingly strong magnetic field for its size. Tidal effects from Jupiter continually stretch and squeeze the moon, keeping its core warm and driving the magnetic field. But the exact geological processes occurring within the core are not fully understood. Now, a new experimental study has put one of the leading models of core dynamics to the test: the formation of crystalized ‘iron snow’

The iron snow theory is like a geological ‘weather model’ for a planetary core: it describes how iron cools and crystalizes near the upper edge of the core (where it meets the mantle), then falls inwards and melts back into the liquid centre of the planet.

Ganymede’s core, in other words, is a molten metal snowglobe, shaken and stirred by Jupiter’s gravity.

Sometimes big science comes in small packages.

Unveil the proximity in Hubble’s cosmic snapshot showcasing the challenges of interpreting cosmic distances in two-dimensional space.

Explore the Hubble Space Telescope’s cosmic portrait, revealing proximities between galaxies and challenging perceptions of cosmic distances.

The first Indian solar observatory has successfully reached its intended orbit, the country’s Space Research Organisation announced Saturday, as India seeks to cement its status as an emerging space superpower.

The Aditya-L1 spacecraft safely arrived at Lagrange Point L1, the position in space with unobstructed views of the sun located about 1.5 million kilometers (almost a million miles) from Earth, paving the way for scientists to enhance their study of the Sun-Earth System.

Indian Prime Minister Narendra Modi applauded the “extraordinary feat” in a post on X on Saturday, adding that this “is a testament to the relentless dedication of our scientists in realizing among the most complex and intricate space missions.”