By Brian Koberlein
March 24, 2025
One of the surprising discoveries of the James Webb Space Telescope (JWST) is that galaxies formed very early in the Universe. JWST has discovered about two dozen galaxies at a redshift of around z = 14, meaning that we see them at a time when the cosmos was just 300-500 million years old. The most distant galaxy, JADES-GS-z14-0, is seen at an age of less than 300 million years. All of these galaxies are rich with stars and have a basic structure similar to what we see in more modern galaxies. This discovery challenged our understanding of galactic evolution. Now a new discovery challenges it even further.
Continue reading
By Carolyn Collins Petersen
March 23, 2025
What's on and in a star? What happens at an active galactic nucleus? Answering those question is the goal of a proposed giant interferometer on the Moon. It's called Artemis-enabled Stellar Imager (AeSI) and would deploy a series of 15-30 optical/ultraviolet-sensitive telescopes in a 1-km elliptical array across the lunar surface.
Continue reading
By Paul Sutter
March 23, 2025
In the years since Miguel Alcubierre came up with a warp drive solution in 1994, you would occasionally see news headlines saying that warp drives can work. And then a few months later you’ll see that they’ve been ruled out. And then after that you’ll see that warp drives kind of work, but only in limited cases. It seems to constantly go around and around without a clear answer.
What gives?
Continue reading
By Brian Koberlein
March 23, 2025
There is a supermassive black hole at the center of our galaxy. There is also a lot of other stuff there as well. Young stars, gas, dust, and stellar-mass black holes. It's a happening place. It is also surrounded by a veil of interstellar gas and dust, which means we can't observe the region in visible light. We can observe stars in the region through infrared and radio, and some of the gas there emits radio light, but the stellar-mass black holes remain mostly a mystery.
Continue reading
By Matthew Williams
March 23, 2025
Welcome back to our five-part examination of Webb's Cycle 4 General Observations program. In the first and second installments, we examined how some of Webb's 8,500 hours of prime observing time this cycle will be dedicated to exoplanet characterization, the study of galaxies at "Cosmic Dawn," the period known as "Cosmic Noon," and the study of star formation and evolution.
In our final installment, we'll examine programs that leverage Webb's unique abilities to study objects in our cosmic backyard—the Solar System!
Continue reading
By Paul Sutter
March 22, 2025
In 1994 Miguel Alcubierre was able to construct a valid solution to the equations of general relativity that enable a warp drive. But now we need to tackle the rest of relativity: How do we arrange matter and energy to make that particular configuration of spacetime possible?
Continue reading
By Brian Koberlein
March 22, 2025
There are three known types of black holes: supermassive black holes that lurk in the hearts of galaxies, stellar mass black holes formed from stars that die as supernovae, and intermediate mass black holes with masses between the two extremes. It's generally thought that the intermediate ones form from the mergers of stellar mass black holes. If that is true, there should be a forbidden range between stellar and intermediate masses. A range where the mass is too large to have formed from a star but too small to be the sum of mergers. But a new study of data from LIGO suggests that there are black holes in that forbidden range.
Continue reading
By Paul Sutter
March 21, 2025
To make a warp drive you have to arrange spacetime so that you never locally travel faster than light but still arrive at your destination…faster than light. And in 1994 Mexican physicist Miguel Alcubierre figured out how.
Continue reading
By Evan Gough
March 21, 2025
The European Space Agency is considering a mission to a metal-rich asteroid. The target is Kleopatra, an M-type asteroid with two moons. These asteroids are relatively common, but they're difficult to observe because they're in the middle and outer regions of the main asteroid belt.
Continue reading
By Mark Thompson
March 21, 2025
Firefly Aerospace's Blue Ghost 1 has completed its brief lunar mission. The lander spent two weeks conducting operations on the surface of the Moon before witnessing its final sunset as the Sun dipped below the horizon. This sunset marked the end of the mission, as Blue Ghost lacks the capability to maintain warmth during the freezing cold lunar night. Despite its short operational period, the lander accomplished its objectives, successfully testing all ten NASA payloads, gathering valuable data, and transmitting the findings back to Earth.
Continue reading