How Long is a Day on Venus? Astronomers Make Their Best Measurement Yet

There’s a problem with Venus. We don’t know how fast it rotates. For a space-faring civilization like ours, that’s a problem.

Measuring the length of day, or rotation rate, of most bodies is pretty straightforward. Mark a prominent surface feature and time how long it takes to rotate 360 degrees. But Venus is blanketed in thick clouds. Those clouds give it its reflectivity, and make it bright and noticeable in the sky, but they make it hard to measure Venus’ day length.

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Some Quasars Shine With the Light of Over a Trillion Stars

Quasars are some of the brightest objects in the Universe. The brightest ones are so luminous they outshine a trillion stars. But why? And what does their brightness tell us about the galaxies that host them?

To try to answer that question, a group of astronomers took another look at 28 of the brightest and nearest quasars. But to understand their work, we have to back track a little, starting with supermassive black holes.

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Planet Sizes Matter for Habitability Too.

In order to be considered habitable, a planet needs to have liquid water. Cells, the smallest unit of life, need water to carry out their functions. For liquid water to exist, the temperature of the planet needs to be right. But how about the size of the planet?

Without sufficient mass a planet won’t have enough gravity to hold onto its water. A new study tries to understand how size affects the ability of a planet to hold onto its water, and as a result, its habitability.

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This is What Moondust Looks Like When You Remove All the Oxygen. A Pile of Metal

The Moon has abundant oxygen and minerals, things that are indispensable to any space-faring civilization. The problem is they’re locked up together in the regolith. Separating the two will provide a wealth of critical resources, but separating them is a knotty problem.

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Power Grids and Satellites Are More at Risk from Extreme Solar Storms Than We Thought

Exactly how dangerous are solar storms? Scientists think the Carrington Event was one of the most powerful ones to ever hit Earth. They also think that storms that powerful only happen every couple centuries or so. But a new study says we can expect more storms equally as strong, and more often.

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China’s Lander Successfully Grew Some Cotton Plants on the Moon. Fruit Flies and Potatoes Didn’t Fare So Well

When China’s Chang’e-4 spacecraft landed on the lunar far side on January 3rd 2019, it made history. It was the first spacecraft to visit that part of the Moon, and among its payload was a 2.6 kg (5.7 lb) mini-biosphere called the Lunar Micro Ecosystem (LME).

The sealed, cylindrical biosphere is only 18 cm (7.1 in) long and 16 cm (6.3 in) in diameter. The LME carried six lifeforms, kept in mostly Earth-like conditions except for micro-gravity and lunar radiation.

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A Red Dwarf Star Has a Jupiter-Like Planet. So Massive it Shouldn’t Exist, and Yet, There It Is

Thanks to the Kepler mission and other efforts to find exoplanets, we’ve learned a lot about the exoplanet population. We know that we’re likely to find super-Earths and Neptune-mass exoplanets orbiting low-mass stars, while larger planets are found around more massive stars. This lines up well with the core accretion theory of planetary formation.

But not all of our observations comply with that theory. The discovery of a Jupiter-like planet orbiting a small red dwarf means our understanding of planetary formation might not be as clear as we thought. A second theory of planetary formation, called the disk instability theory, might explain this surprising discovery.

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Mice That Spend a Month in Space Were Able to Reproduce Once They Got Back to Earth

The International Space Station (ISS), seen here with Earth as a backdrop. Credit: NASA

A team of Japanese researchers have used sperm from mice that spent time aboard the International Space Station (ISS) to fertilize female mice back on Earth. While previous research has shown that freeze-dried mouse sperm stored in space can experience radiation damage, these results show that the sperm from live mice may not suffer the same damage.

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Elliptical Galaxy Messier 110 Has a Surprising Core of Hot Blue Stars

Messier 110 (NGC 205) is a satellite of the Andromeda Galaxy. It’s a dwarf elliptical galaxy, a common type of galaxy often found in galaxy clusters and groups, and it contains about 10 billion stars. Like all dwarf ellipticals, it doesn’t have the characteristic shape of galaxies like Andromeda or the Milky Way, with their vast, spiral arms. It has a smooth, featureless shape.

Dwarf ellipticals lack the blazing bright areas of active star formation that other galaxies display. In fact, astronomers think that they’re too old to have any young stars at all. But M110 appears to be different.

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