"Professor Goddard does not know the relation between action and reaction and the need to have something better than a vacuum against which to react. He seems to lack the basic knowledge ladled out daily in high schools."
--1921 New York Times editorial about Robert Goddard's revolutionary rocket work.

"Correction: It is now definitely established that a rocket can function in a vacuum. The 'Times' regrets the error."
NY Times, July 1969.

— New York Times

Astronomy

SpaceX sends two batches of Starlink satellites on Saturday doubleheader (video)

Space.com - Sat, 06/28/2025 - 12:37am
Two SpaceX Falcon 9 rockets lifted off with Starlink satellites on June 28, 2025. The first launched from Cape Canaveral, Florida and the second from Vandenberg Space Force Station in California.
Categories: Astronomy

A New Way to Detect Primordial Black Holes Through Their Hawking Radiation

Universe Today - Fri, 06/27/2025 - 9:56pm

Scientists propose a revolutionary new method to detect primordial black holes by hunting for their Hawking radiation. Instead of searching for faint background signals, researchers suggest using the Alpha Magnetic Spectrometer on the International Space Station to watch for distinctive spikes in positron particles as these ancient black holes pass through our solar system, emitting Hawking radiation.

Categories: Astronomy

A Statistical Analysis of Exoplanet Habitability Turns Up One Great Candidate - And Significant Observational Bias

Universe Today - Fri, 06/27/2025 - 9:56pm

The search for life beyond our planet continues, and one of the most underappreciated tools in an astrobiologists' toolkit is statistics. While it might not be as glamorous as directly imaging a planet’s atmosphere or finding a system with seven planets in it, statistics is absolutely critical if we want to be sure that what we’re seeing is real and not just an artifact of the data, or of our observational techniques themselves. A new paper by Caleb Traxler and their co-authors at the Department of Information and Computer Science at UC Irvine takes on that challenge head-on by statistically analyzing a set of about 10% of the total number of exoplanets found and judging their habitability.

Categories: Astronomy

The Galactic Center Isn't Spitting Out Stars. What Does This Mean?

Universe Today - Fri, 06/27/2025 - 9:56pm

Sometimes a non-detection can tell you a lot. For example, astronomers recently searched through data containing around 5 million stars captured by the Dark Energy Spectroscopic Instrument. They were looking for stars that had been ejected from the center of the Milky Way galaxy, through the gravitational interaction of the supermassive black hole Sgr A*. They failed to find any obvious candidates, which suggests that Sgr A* hasn't merged with another black hole recently.

Categories: Astronomy

NASA Just Launched A Mission To Calibrate Space-Based Instruments With Moonlight

Universe Today - Fri, 06/27/2025 - 9:56pm

Calibration is a necessary, if typically invisible, step in the successful operation of any scientific telescope. Without a known value to compare its readings against, data from telescopes could suffer from biases or transients that could completely misdirect scientists analyzing it. However, those same scientists also struggle to find good sources of data to calibrate against. Enter Arcstone - a technology demonstration mission that launched earlier this week that plans to use one particular source as a calibration dataset - moonlight.

Categories: Astronomy

Weather Forecasters Lose Crucial Hurricane Detection Microwave Satellite Data

Scientific American.com - Fri, 06/27/2025 - 5:00pm

Microwave satellite data are key to capturing major changes in a hurricane’s strength, such as when a storm undergoes rapid intensification. But a main source of those data is being abruptly shut off

Categories: Astronomy

Look for the 'Other Dipper' this summer: How to find Ursa Minor, the Little Bear with a little help from the North Star

Space.com - Fri, 06/27/2025 - 5:00pm
Most people have never seen the Little Dipper, because most of its stars are too dim to be seen through light-polluted skies.
Categories: Astronomy

X-ray boosting fabric could make mammograms less painful

New Scientist Space - Cosmology - Fri, 06/27/2025 - 3:00pm
A flexible fabric called X-Wear could replace some parts of medical scanners, which would make taking X-rays and CT scans far more comfortable and convenient
Categories: Astronomy

Astronaut Joe Engle Flies X-15

NASA Image of the Day - Fri, 06/27/2025 - 1:51pm
In 1963, Captain Engle was assigned as one of two Air Force test pilots to fly the X-15 Research Rocket aircraft. In 1965, he flew the X-15 to an altitude of 280,600 feet, and became the youngest pilot ever to qualify as an astronaut. Three of his sixteen flights in the X-15 exceeded the 50-mile (264,000 feet) altitude required for astronaut rating.
Categories: Astronomy, NASA

Mathematicians create a tetrahedron that always lands on the same side

New Scientist Space - Cosmology - Fri, 06/27/2025 - 12:47pm
With the help of powerful computers, researchers discovered a four-sided shape that naturally rests on one side, and built a real-life version from carbon fibre and tungsten
Categories: Astronomy

The bold plan to save a vital ocean current with giant parachutes

New Scientist Space - Cosmology - Fri, 06/27/2025 - 12:30pm
Large sea anchors could be used to drag water under a bold plan to keep the Atlantic Meridional Overturning Circulation moving – but some experts are sceptical
Categories: Astronomy

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APOD - Fri, 06/27/2025 - 12:00pm


Categories: Astronomy, NASA