Universe Today

November 7, 2024November 7, 2024 by Brian Koberlein

You Can Build a Home Radio Telescope to Detect Clouds of Hydrogen in the Milky Way

The 1-meter dish of a home radio telescope. Credit: Jack Phelps

If I ask you to picture a radio telescope, you probably imagine a large dish pointing to the sky, or even an array of dish antennas such as the Very Large Array. What you likely don’t imagine is something that resembles a TV dish in your neighbor’s backyard. With modern electronics, it is relatively easy to build your own radio telescope. To understand out how it can be done, check out a recent paper by Jack Phelps.

November 6, 2024November 6, 2024 by Evan Gough

A Space Walking Robot Could Build a Giant Telescope in Space

Artist impression of the James Webb Space Telescope. Its design and construction were made more complicated and expensive because it had to fit into the nosecone of the rocket that launched it. Assembling telescopes in space could be an improvement. Image Credit: ESA.

The Hubble Space Telescope was carried to space inside the space shuttle Discovery and then released into low-Earth orbit. The James Webb Space Telescope was squeezed inside the nose cone of an Ariane 5 rocket and then launched. It deployed its mirror and shade on its way to its home at the Sun-Earth L2 Lagrange point.

However, the ISS was assembled in space with components launched at different times. Could it be a model for building future space telescopes and other space facilities?

November 5, 2024November 5, 2024 by Matt Williams

New Report Details What Happened to the Arecibo Observatory

The Arecibo Radio Telescope. Though it's decommissioned now, Arecibo Data may explain 1977's mysterious Wow! Signal. Image Credit: UCF

In 1963, the Arecibo Observatory became operational on the island of Puerto Rico. Measuring 305 meters (~1000 ft) in diameter, Arecibo’s spherical reflector dish was the largest radio telescope in the world at the time – a record it maintained until 2016 with the construction of the Five-hundred-meter Aperture Spherical Telescope (FAST) in China. In December 2020, Arecibo’s reflector dish collapsed after some of its support cables snapped, leading the National Science Foundation (NSF) to decommission the Observatory.

Shortly thereafter, the NSF and the University of Central Florida launched investigations to determine what caused the collapse. After nearly four years, the Committee on Analysis of Causes of Failure and Collapse of the 305-Meter Telescope at the Arecibo Observatory released an official report that details their findings. According to the report, the collapse was due to weakened infrastructure caused by long-term zinc creep-induced failure in the telescope’s cable sockets and previous damage caused by Hurricane Maria.

November 5, 2024November 5, 2024 by Brian Koberlein

We Understand Rotating Black Holes Even Less Than We Thought

Illustration of an exotic black hole. Credit: Alex Antropov, via Pixabay

Black holes are real. We see them throughout the cosmos, and have even directly imaged the supermassive black hole in M87 and our own Milky Way. We understand black holes quite well, but the theoretical descriptions of these cosmic creatures still have nagging issues. Perhaps the most famous issue is that of the singularity. According to the classical model of general relativity, all the matter that forms a black hole must be compressed into an infinite density, enclosed within a sphere of zero volume. We assume that somehow quantum physics will avert this problem, though without a theory of quantum gravity, we aren’t sure how. But the singularity isn’t the only infinite problem. Take, for example, the strange boundary known as the Cauchy horizon.

November 5, 2024November 5, 2024 by Evan Gough

Habitable Worlds are Found in Safe Places

Illustration of Kepler-186f, a recently-discovered, possibly Earthlike exoplanet that could be a host to life. (NASA Ames, SETI Institute, JPL-Caltech, T. Pyle) — This is Kepler 186f, an exoplanet in the habitable zone around a red dwarf. We've found many planets in their stars' habitable zones where they could potentially have surface water. But it's a fairly crude understanding of true habitability. Image Credit: NASA Ames, SETI Institute, JPL-Caltech, T. Pyle)

When we think of exoplanets that may be able to support life, we hone in on the habitable zone. A habitable zone is a region around a star where planets receive enough stellar energy to have liquid surface water. It’s a somewhat crude but helpful first step when examining thousands of exoplanets.

However, there’s a lot more to habitability than that.

November 5, 2024November 5, 2024 by Nancy Atkinson

New Glenn Booster Moves to Launch Complex 36

Blue Origin's New Glenn Rocket, heading to Launch Complex 36. Credit: Blue Origin/Dave Limp.

Nine years ago, Blue Origin revealed the plans for their New Glenn rocket, a heavy-lift vehicle with a reusable first stage that would compete with SpaceX for orbital flights. Since that time, SpaceX has launched hundreds of rockets, while Blue Origin has been working mostly in secret on New Glenn. Last week, the company rolled out the first prototype of the first-stage booster to the launch complex at Cape Canaveral Space Force Station. If all goes well, we could see a late November test on the launch pad.

The test will be an integrated launch vehicle hot-fire which will include the second stage and a stacked payload.

November 5, 2024November 5, 2024 by Brian Koberlein

How Many Additional Exoplanets are in Known Systems?

One thing we’ve learned in recent decades is that exoplanets are surprisingly common. So far, we’ve confirmed nearly 6,000 planets, and we have evidence for thousands more. Most of these planets were discovered using the transit method. though we there are other methods as well. Many stars are known to have multiple planets, such as the TRAPPIST-1 system with seven Earth-sized worlds. But even within known planetary systems there could be planets we’ve overlooked. Perhaps their orbit doesn’t pass in front of the star from our vantage point, or the evidence of their presence is buried in data noise. How might we find them? A recent paper on the arXiv has an interesting approach.

November 5, 2024November 5, 2024 by Allen Versfeld

Hubble and Webb are the Dream Team. Don't Break Them Up

Webb and Hubble's Views of Spiral Galaxy NGC 628 Image credit: NASA's Scientific Visualization Studio - Global Science and Technology, Inc./Amy Moran

Many people think of the James Webb Space Telescope as a sort of Hubble 2. They understand that the Hubble Space Telescope (HST) has served us well but is now old, and overdue for replacement. NASA seems to agree, as they have not sent a maintenance mission in over fifteen years, and are already preparing to wind down operations. But a recent paper argues that this is a mistake. Despite its age, HST still performs extremely well and continues to produce an avalanche of valuable scientific results. And given that JWST was never designed as a replacement for HST — it is an infrared (IR) telescope) — we would best be served by operating both telescopes in tandem, to maximize coverage of all observations.

November 4, 2024November 4, 2024 by Matt Williams

Scientists Have Figured out why Martian Soil is so Crusty

Artist's concept of InSight "taking the pulse of Mars". Credit: NASA/JPL-Caltech

On November 26th, 2018, NASA’s Interior Exploration using Seismic Investigations, Geodesy, and Heat Transport (InSight) mission landed on Mars. This was a major milestone in Mars exploration since it was the first time a research station had been deployed to the surface to probe the planet’s interior. One of the most important instruments InSight would use to do this was the Heat Flow and Physical Properties Package (HP³) developed by the German Aerospace Center (DLR). Also known as the Martian Mole, this instrument measured the heat flow from deep inside the planet for four years.

The HP³ was designed to dig up to five meters (~16.5 ft) into the surface to sense heat deeper in Mars’ interior. Unfortunately, the Mole struggled to burrow itself and eventually got just beneath the surface, which was a surprise to scientists. Nevertheless, the Mole gathered considerable data on the daily and seasonal fluctuations below the surface. Analysis of this data by a team from the German Aerospace Center (DLR) has yielded new insight into why Martian soil is so “crusty.” According to their findings, temperatures in the top 40 cm (~16 inches) of the Martian surface lead to the formation of salt films that harden the soil.

November 4, 2024November 4, 2024 by Brian Koberlein

Another Way to Extract Energy From Black Holes?

Illustration of a powerful black hole and its magnetic field. Credit: L. Calçada/ESO

The gravitational field of a rotating black hole is powerful and strange. It is so powerful that it warps space and time back upon itself, and it is so strange that even simple concepts such as motion and rotation are turned on their heads. Understanding how these concepts play out is challenging, but they help astronomers understand how black holes generate such tremendous energy. Take, for example, the concept of frame dragging.