Cygnus X-1 was the First Black Hole Ever Found. New Measurements Show it's Much More Massive Than Previously Believed

In 1964 two Aerobee suborbital rockets were launched with the goal of mapping x-ray sources in the sky. Each rocket contained a directed Geiger counter, so that as the rocket rotated at the peak of its trajectory to measure the direction of x-ray sources. The project discovered eight x-ray sources, including a particularly bright one in the constellation Cygnus. It became known as Cygnus X-1.

Cygnus X-1 as imaged by a balloon bourne telescope. Credit: NASA/Marshall Space Flight Center
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Since Perseverance is Searching for Life, What Will it Be Looking for?

You have to be careful what you say to people. When NASA or someone else says that the Perseverance rover will be looking for fossil evidence of ancient life, the uninformed may guffaw loudly. Or worse, they may think that scientists are looking for actual animal skeletons or something.

Of course, that’s not the case.

So what is Perseverance looking for?

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A map of 25,000 Supermassive Black Holes Across the Universe

The Low-Frequency Array (LOFAR) is a different kind of radio telescope. Although radio light has the longest wavelengths and lowest frequencies of the electromagnetic spectrum, much of radio astronomy has focused on the higher frequency end. Observatories such as ALMA study radio light at frequencies of hundreds of Gigahertz, and the VLA studies the fifty Gigahertz range, LOFAR captures radio signals below 250 Megahertz, which is in the range of the lowest radio frequencies that can be seen from Earth.

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How Long Will Space Junk Take to Burn Up? Here’s a Handy Chart

An artist's illustration of space junk. The problem isn't this bad yet, but it's getting worse year by year. Image: Tohoku University

If the Roman Empire had been able to launch a satellite in a relatively high Low Earth Orbit – say about 1,200 km (750 miles) in altitude – only now would that satellite be close to falling back to Earth. And if the dinosaurs had launched a satellite into the furthest geostationary orbit – 36,000 km (23,000 miles) or higher — it might still be up there today.

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There’s Evidence That Mars Once Had an Atmosphere With Less Oxygen. A Possible Biosignature For Life?

Remote sensing is only useful if scientists have an idea of what they are looking at.  That knowledge is especially important for remote sensing applications on other planets, such as Mars, where it is extraordinarily difficult to collect information about an observed object in any other way.  To make up for the lack of ability to perform other tests in situ, scientists set up laboratory experiments with different environments and materials and compare the remote sensing data with the observed remote objects. 

That is exactly what Jiacheng Liu, a doctoral student at the University of Hong Kong, did with remote sensing data from the surface of Mars.  What he found gave new weight to a novel theory – that Mars didn’t used to have a significant amount of oxygen in its atmosphere.  The fact that it does now prompts the question of where all the oxygen that exists in the atmosphere today came from.  One possible answer is the same place it came from on Earth – photosynthetic life.

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The Mars Helicopter is Online and Getting Ready to Fly

Earth is the only planet in the solar system with aircraft capable of sustained flight. Suppose the ground-breaking Ingenuity helicopter, currently stowed aboard the similarly spectacular Mars Perseverance rover, accomplishes its planned mission. In that case, Mars will become the second planet to have a powered aircraft fly through its atmosphere. 

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Protogalaxy Cluster Found When the Cosmic Fog Was Starting to Clear, When the Universe Was Just 750 Million Years Old

Origin stories are a focus of many astronomical studies.  Planetary formation, solar system formation, and even galaxy formation have long been studied in order to understand how the universe came to be where it is today.  Now, a team of scientists from the Lyman Alpha Galaxies in the Epoch of Reionization (LAGER) consortium have found an extremely early “protogalaxy” that was formed approximately 750 million years after the big bang.  Studying it can provide insights into that early type of galaxy formation and everything that comes after.

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