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October 4, 2021October 4, 2021 by Matt Williams

A Technique to Find Oceans on Other Worlds

Artist’s impression of a sunset seen from the surface of an Earth-like exoplanet. Credit: ESO/L. Calçada

You could say that the study of extrasolar planets is in a phase of transition of late. To date, 4,525 exoplanets have been confirmed in 3,357 systems, with another 7,761 candidates awaiting confirmation. As a result, exoplanet studies have been moving away from the discovery process and towards characterization, where follow-up observations of exoplanets are conducted to learn more about their atmospheres and environments.

In the process, exoplanet researchers hope to see if any of these planets possess the necessary ingredients for life as we know it. Recently, a pair of researchers from Northern Arizona University, with support from the NASA Astrobiology Institute’s Virtual Planetary Laboratory (VPL), developed a technique for finding oceans on exoplanets. The ability to find water on other planets, a key ingredient in life on Earth, will go a long way towards finding extraterrestrial life.

October 3, 2021October 3, 2021 by Matt Williams

Astronomers Look at Super-Earths That had Their Atmospheres Stripped Away by Their Stars

Figure 1: Artist’s conceptual image showing the sizes of the planets observed in this study. The radius of TOI-1634 is 1.5 times larger than Earth’s radius and TOI-1685 is 1.8 times larger. The planets would appear red, due to the light from the red dwarf stars they orbit. (Credit: Astrobiology Center, NINS)

As the planets of our Solar System demonstrate, understanding the solar dynamics of a system is a crucial aspect of determining habitability. Because of its protective magnetic field, Earth has maintained a fluffy atmosphere for billions of years, ensuring a stable climate for life to evolve. In contrast, other rocky planets that orbit our Sun are either airless, have super-dense (Venus), or have very thin atmospheres (Mars) due to their interactions with the Sun.

In recent years, astronomers have been on the lookout for this same process when studying extrasolar planets. For instance, an international team of astronomers led by the National Astronomical Observatory of Japan (NAOJ) recently conducted follow-up observations of two Super-Earths that orbit very closely to their respective stars. These planets, which have no thick primordial atmospheres, represent a chance to investigate the evolution of atmospheres on hot rocky planets.

October 3, 2021October 3, 2021 by Matt Williams

Communication With Mars is About to Become Impossible (for two Weeks)

Every two years, Mars enters what is known as a “Solar Conjunction,” where its orbit takes it behind the Sun relative to Earth. During these periods, the hot plasma regularly expelled by the Sun’s corona can cause interference with radio signals transmitted between Earth and Mars. To avoid signal corruption and the unexpected behaviors that could result, NASA and other space agencies declare a moratorium on communications for two weeks.

What this means is that between Oct. 2nd and Oct. 16th, all of NASA’s Mars missions will experiencing what is known as a “commanding moratorium.” This will consist of NASA sending a series of simple commands to its missions in orbit, which will then be dispatched to landers and rovers on the surface. These simple tasks will keep all of the robotic Martian explorers busy until regular communications can be established.

September 28, 2021September 29, 2021 by Matt Williams

How Much Carbon Dioxide Snow Falls Every Winter on Mars?

Mars’ south polar ice cap. Credit: ESA / DLR / FU Berlin /

Like Earth, Mars experiences climatic variations during the course of a year because of the obliquity of its rotational axis. This leads to the annual deposition/sublimation of the CO2 ice/snow, which results in the formation of the seasonal polar caps. Similarly, these variations in temperature result in interaction between the atmosphere and the polar ice caps, which has a seasonal effect on surface features.

On Mars, however, things work a little differently. In addition to water ice, a significant percentage of the Martian polar ice caps are made up of frozen carbon dioxide (“dry ice”). Recently, an international team of scientists used data from NASA’s Mars Global Surveyor (MGS) mission to measure how the planet’s polar ice caps grow and recede annually. Their results could provide new insights into how the Martian climate varies due to seasonal change.

September 28, 2021September 29, 2021 by Matt Williams

Vera Rubin Observatory Should Find 5 Interstellar Objects a Year, Many of Which we Could Chase Down With Spacecraft

The Vera C. Rubin Observatory is under construction at Cerro Pachon, in Chile. This image shows construction progress in late 2019. The VCO should be able to spot interstellar objects like Oumuamua. Image Credit: Wil O'Mullaine/LSST CC BY-SA 4.0, https://en.wikipedia.org/w/index.php?curid=62504391

In a year (perhaps two), the Vera C. Rubin Observatory in Chile will become operational and commence its 10-year Legacy Survey of Space and Time (LSST). Using its 8.4-meter (27 foot) mirror and 3.2 gigapixel camera, this observatory is expected to collect 500 petabytes of images and data. It will also address some of the most pressing questions about the structure and evolution of the Universe and everything in it.

One of the highly-anticipated aspects of the LSST is how it will allow astronomers to locate and track interstellar objects (ISOs), which have become of particular interest since `Oumuamua flew through our system in 2017. According to a recent study by a team from the University of Chicago and the Harvard-Smithsonian Center for Astrophysics (CfA), the Rubin Observatory will detect around 50 objects during its 10-year mission, many of which we will be able to study up-close using rendezvous missions.

September 28, 2021September 28, 2021 by Matt Williams

China’s First Space Station Crew is Back From Orbit

On Friday, Sept. 17th, three Chinese astronauts returned safely from space following a three-month stay aboard the new Tiangong space station. This was a major milestone for the Chinese Manned Space (CMS) program, which beats its previous record for the longest crewed mission to space. Whereas the Shenzhou 11 mission (2016) lasted 33 days, the crew of Tang Hongbo, Nie Haisheng, and Liu Boming spent a total of 92 days in orbit.

September 26, 2021September 26, 2021 by Matt Williams

Astronomers Detect Clouds on an Exoplanet, and Even Measure Their Altitude

The search for planets beyond our Solar System has grown immensely during the past few decades. To date, 4,521 extrasolar planets have been confirmed in 3,353 systems, with an additional 7,761 candidates awaiting confirmation. With so many distant worlds available for study (and improved instruments and methods), the process of exoplanet studies has been slowly transitioning away from discovery towards characterization.

For example, a team of international scientists recently showed how combining data from multiple observatories allowed them to reveal the structure and composition of an exoplanet’s upper atmosphere. The exoplanet in question is WASP-127b, a “hot Saturn” that orbits a Sun-like star located about 525 light-years away. These findings preview how astronomers will characterize exoplanet atmospheres and determine if they are conducive to life as we know it.

September 24, 2021September 24, 2021 by Matt Williams

The Future Could Bring Pinpoint Deliveries From Orbit

Since the dawn of the Space Age, considerable progress has been made with launch vehicles. From single stage to multistage rockets and spaceplanes to reusable launch vehicles, we have become very good at sending payloads to space. But when it comes to returning payloads to Earth, our methods really haven’t evolved much at all. Some seventy years later, we are still relying on air friction, heatshields, and parachutes and landing at sea more often than not.

Luckily, there are many solutions that NASA and commercial space companies are currently investigating. For example, SpaceWorks Enterprises, Inc (SEI) is currently working on an orbital delivery system known as Reentry Device (RED) capsules. With support provided by NASA, they are gearing up for a test run this October where one of their capsules gets dropped from an altitude of 30 km (19 mi).

September 23, 2021September 23, 2021 by Matt Williams

Although it’s Quiet Today, Mars Once had Thousands of Volcanic Eruptions on its Surface

Sarychev volcano, (located in Russia's Kuril Islands, northeast of Japan) in an early stage of eruption on June 12, 2009. Credit: NASA

Earth is a geologically active planet, which means it has plate tectonics and volcanic eruptions that have not ceased. This activity extends all the way to the core, where action between a liquid outer core and a solid inner core generates a planetary magnetic field. In comparison, Mars is an almost perfect example of a “stagnant lid” planet, where geological activity billions of years ago and the surface has remained stagnant ever since.

But as indicated by the many mountains on Mars, which includes the tallest in the Solar System (Olympus Mons), the planet was once a hotbed of volcanic activity. And according to a recent NASA-supported study, there is evidence that thousands of “super-eruptions” happened in the Arabia Terra region in northern Mars 4 billion years ago. These eruptions occurred over the course of 500-million years and had a drastic effect on the Martian climate.

September 22, 2021September 25, 2021 by Matt Williams

A Particle Physics Experiment Might Have Directly Observed Dark Energy

An illustration of cosmic expansion. Credit: NASA's Goddard Space Flight Center Conceptual Image Lab

About 25 years ago, astrophysicists noticed something very interesting about the Universe. The fact that it was in a state of expansion had been known since the 1920s, thanks to the observation of Edwin Hubble. But thanks to the observations astronomers were making with the space observatory that bore his name (the Hubble Space Telescope), they began to notice how the rate of cosmic expansion was getting faster!

This has led to the theory that the Universe is filled with an invisible and mysterious force, known as Dark Energy (DE). Decades after it was proposed, scientists are still trying to pin down this elusive force that makes up about 70% of the energy budget of the Universe. According to a recent study by an international team of researchers, the XENON1T experiment may have already detected this elusive force, opening new possibilities for future DE research.