The Inner and Outer Milky Way Aren’t the Same Thickness, and that’s Surprising

Illustration depicting the Smith Cloud on its journey to the Milky Way Creator: NRAO/AUI/NSF Credit: B. Saxton, NRAO/AUI/NSF

At first glance, the universe and night sky seem largely unchanging. The reality is very different, even now, a gas cloud is charging toward the Milky Way Galaxy and is expected to crash into us in 27 million years. A team of astronomers hoping to locate the exact position of the expected impact site have been unsuccessful but have accidentally measured the thickness of the Milky Way! Analysing radio data, they have been able to deduce the thickness of the inner and outer regions and discovered a dramatic difference between the two. 

Continue reading “The Inner and Outer Milky Way Aren’t the Same Thickness, and that’s Surprising”

Part 2: The History and Future of Planetary Radar

The Green Bank Observatory in summer. Credit: NSF/GBO/Jill Malusky

To reach the U.S. National Science Foundation’s Green Bank Observatory, you take the road less traveled, winding through scenic and remote regions of the Allegheny Mountains and the Monongahela National Forest of West Virginia. About an hour away, you’ll start to lose cell phone service. The Green Bank Observatory – a collection of radio telescopes that search the heavens for faint radio signals from black holes, pulsars, neutron stars or gravitational waves — sits near the heart of the United States National Radio Quiet Zone, a unique area the encompasses an area of approximately 13,000 square miles, spanning the border between Virginia and West Virginia.

Here in the NRQZ, human-generated radio transmissions are limited to shield the radio telescopes from Earth-based radio signals called RFI (Radio Frequency Interference), which are high-frequency electromagnetic waves that emanate from electronic devices such as computers, cell phones, microwave ovens, and even digital cameras. Even the weakest RFI signals can drown out the faint radio waves coming from the cosmos.

Continue reading “Part 2: The History and Future of Planetary Radar”

Next-Generation Radar Will Map Threatening Asteroids

The Robert C. Byrd Green Bank Telescope. Credit: Jay Young.

When the Arecibo Observatory dish in Puerto Rico collapsed in 2020, astronomers lost a powerful radio telescope and a unique radar instrument to map the surfaces of asteroids and other planetary bodies. Fortunately, a new, next-generation radar system called ngRADAR is under development, to eventually be installed at the the U.S. National Science Foundation’s 100-meter (328 ft.) Green Bank Telescope (GBT) in West Virginia. It will be able to track and map asteroids, with the ability to observe 85% of the celestial sphere. It will also be able to study comets, moons and planets in our Solar System.

“Right now, there is only one facility that can conduct high-power planetary radar, the 70-meter (230-foot) Goldstone antenna that is part of NASA’s Deep Space network,” said Patrick Taylor, the project director for ngRADAR and the radar division head for the National Radio Astronomy Observatory. “We had begun this process of developing a next generation radar system several years ago, but with the loss of Arecibo, this becomes even more important.”

Continue reading “Next-Generation Radar Will Map Threatening Asteroids”