Perseverance used a Mars-based alignment to record Earth behind Phobos, while a cold-atom simulator used thermodynamic and spectroscopic measurements to reveal the Hubbard model's crossover into a pseudogap metal.
Science··Morning
Earth disappeared as a single-pixel point
NASA's 5 August release presents an image sequence acquired by Perseverance's Mastcam-Z camera on 2 July 2026, sol 1,907 of the mission. From the Martian surface, the camera followed Earth as a bright, single-pixel point. As Earth moved across the frame, it passed behind the crescent silhouette of Phobos and reappeared on the other side. The event occurred at about 7 p.m. local solar time on Mars and lasted roughly 40 seconds. Phobos is about 27 km across at its widest, orbits 7,800 km from Mars and crosses the sky three times a day; Earth was 314 million kilometers away. NASA classifies this complete blocking as an occultation, in which a body that appears larger fully covers the one behind it from the observer's viewpoint. Mastcam-Z team member Mark Lemmon said both objects are often visible, yet putting one directly behind the other required planning and some luck. The observation came from combining a selected viewpoint on Mars with alignment at the right moment.[1]
A pseudogap in an atomic simulator
A peer-reviewed study published in Nature on 5 August built another difficult-to-reach arrangement from atoms. The team observed the crossover between a normal metal and a pseudogapped metal in the Hubbard model through thermodynamic and spectroscopic measurements in a cold-atom quantum simulator. The experiment relied on a recent several-fold reduction in achievable temperatures. As the system cooled, compressibility reached a maximum at intermediate doping, which the researchers tracked as a signal of an inflection point in the equation of state. Tracking that maximum across interaction strength traced a line of thermodynamic anomalies separating an underdoped from an overdoped metal at large interactions. In the underdoped regime, lattice-modulation spectra showed a loss of low-energy response. The loss was especially pronounced in the antinodal regions of the Brillouin zone and served as the pseudogap signature. Doped Mott insulators are relevant to cuprate superconductors. The measurement itself belongs to a Hubbard-model simulation built from atoms; no measurement of an actual cuprate sample is reported.[2]
A line of sight and a model arrangement
The reports meet at the construction of an arrangement that permits observation, while the measured scales remain entirely separate. In the Perseverance case, Earth and Phobos move in their own orbits, and the team times their brief overlap along the fixed camera's line of sight from the Martian surface. In the cold-atom experiment, researchers build a model regime from physical atoms, lower the temperature and track compressibility together with lattice-modulation response. The first arrangement reveals one astronomical event; the second reveals a phase diagram that changes with interaction and doping. Their outputs also remain distinct: NASA's sequence documents Earth disappearing behind Phobos from the observer's viewpoint, whereas the Nature study characterizes thermodynamic and spectroscopic signatures of a pseudogap in the Hubbard model. The astronomical event supplies no evidence for the condensed-matter result, and an atomic simulation is not equivalent to an image of distant bodies. Read together, the developments show otherwise inaccessible information being obtained through either a suitable line of sight or a simulation environment that can be measured directly.[1], [2]
