The NASA TESS mission hit a milestone of 5,000 exoplanet candidates or TOIs (TESS Object of Interest). The TESS catalog has been growing steadily since the start of the mission in 2018, and the batch of TOIs boosting the catalog to over 5,000 comes primarily from the Faint Star Search led by MIT postdoc Michelle Kunimoto. Now in its extended mission, TESS is observing the Northern Hemisphere and ecliptic plane, including regions of the sky previously observed by the Kepler and K2 missions, so we can expect more discoveries until 2025.

To discuss this achievement, SETI Institute Senior Astronomer Franck Marchis is joined by Dr. Kunimoto, TESS postdoctoral associate at MIT Kavli Institute. Dr. Kunimoto focuses her work on detecting transiting exoplanets and the statistical determination of exoplanet demographics. She will tell us how astronomers worldwide will study each of these TOIs to confirm whether they are bonafide planets and what we can expect from this complicated task.

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Scientific Reports — Mercury Isotopes as Proxies to Identify Sources and Environmental Impacts of Mercury in Sphalerites. Sci. Rep. 6, 18686; doi: 10.1038/srep18686 (2016).

Thanks to NASA receiving a gift of components from a former spy program, the Nancy Grace Roman Telescope will observe more sky than ever before.

Spacefaring nations have been dumping their junk in the area around the Pacific Ocean’s Point Nemo, the most remote place on Earth, since the 1970s.

This is some send-off.

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NASA recently announced plans to retire the International Space Station by crashing it into the Pacific Ocean — a spacecraft graveyard.

A Southwest Research Institute scientist measured the properties of ice-brine mixtures as cold as-145 degrees Fahrenheit to help confirm that salty water likely exists between grains of ice or sediment under the ice cap at Mars ’ south pole. Laboratory measurements conducted by SwRI geophysicist Dr. David Stillman support oddly bright reflections detected by the MARSIS subsurface sounding radar aboard ESA’s Mars Express orbiter.

With a 130-foot antenna, MARSIS flies over the planet, bouncing radio waves over a selected area and then receiving and analyzing the echoes or reflections. Any near-surface liquid water should send a strong bright signal, whereas the radar signal for ice and rock would be much smaller.

Because conventional models assume the Mars south polar cap experiences temperatures much lower than the melting point of water, many scientists have questioned the presence of liquid water. Clay, hydrated salts, and saline ices have been proposed as potential explanations for the source of the bright basal reflections. The Italian-led team investigating the proposed phenomena used previously published data, simulations, and new laboratory measurements.