Does “Pix or it didn’t happen” apply to traveling to the edge of space on a balloon-lofted solar observatory? Yes, it absolutely does.

The breathtaking views on this page come courtesy of IRIS-2, a compact imaging package that creators [Ramón García], [Miguel Angel Gomez], [David Mayo], and [Aitor Conde] recently decided to release as open source hardware. It rode to the edge of space aboard Sunrise III, a balloon-borne solar observatory designed to study solar magnetic fields and atmospheric plasma flows.

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These latest findings further support the Hubble Space Telescope's prior expansion rate measurements.

Physicists have been puzzling over conflicting observational results pertaining to the accelerating expansion rate of our Universe—a major discovery recognized by the 2011 Nobel Prize in Physics. New observational data from the James Webb Space Telescope (JWST) has confirmed that prior measurements of distances between nearby stars and galaxies made by the Hubble Space Telescope are not in error, according to a new paper published in The Astrophysical Journal. That means the discrepancy between observation and our current theoretical model of the Universe is more likely to be due to new physics.

As previously reported, the Hubble Constant is a measure of the Universe's expansion expressed in units of kilometers per second per megaparsec (Mpc). So, each second, every megaparsec of the Universe expands by a certain number of kilometers. Another way to think of this is in terms of a relatively stationary object a megaparsec away: Each second, it gets a number of kilometers more distant.

How many kilometers? That's the problem here. There are basically three methods scientists use to measure the Hubble Constant: looking at nearby objects to see how fast they are moving, gravitational waves produced by colliding black holes or neutron stars, and measuring tiny deviations in the afterglow of the Big Bang known as the Cosmic Microwave Background (CMB). However, the various methods have come up with different values. For instance, tracking distant supernovae produced a value of 73 km/s Mpc, while measurements of the CMB using the Planck satellite produced a value of 67 km/s Mpc.

Just last year, researchers made a third independent measure of the Universe's expansion by tracking the behavior of a gravitationally lensed supernova, where the distortion in space-time caused by a massive object acts as a lens to magnify an object in the background. The best fits of those models all ended up slightly below the value of the Hubble Constant derived from the CMB, with the difference being within the statistical error. Values closer to those derived from measurements of other supernovae were a considerably worse fit for the data. The method was new, with considerable uncertainties, but it did provide an independent means of getting at the Hubble Constant.

Observations in the past several years, combined with our past knowledge, basically confirmed we live in a weird and unusual part of the universe. Some of those are supported by fairly hard numbers and others are a bit more vague. The famous Drake equation would need several more factors just to cover all relevant information to explain the lack of spacefaring civilizations.

Here are a few new-ish ones, either newly discovered, or just something we didn’t realize is highly relevant in this context.

1. The Sun is not normal. It’s a type G star, this puts it in a group of stars numbering 7.6% of the Milky way. Of those it’s in the 10% most stable type G stars stars. A stable star is probably necessary for life and the factor for a suitable star is around 0.7% at this point.

2. Plate tectonics. In relatively recent times we came to realize plate tectonics are probably important for life, recycling the crust into the mantle without wrecking havoc on the surface every few million years. Of the planets in the Solar system, only Earth has suitable plate tectonics. We don’t know how common they are in the universe, but 10% is probably generous.

3. Rocky planets are typically larger than Earth, around 1.5 times Earth mass. This is relevant, because at 125% the size of Earth you can’t make an orbital chemical rocket any more. If you want a spacefaring civilization you kind of need that, at least as a stepping stone. Let’s call this one at 10%, it shouldn’t be very far off. //

4. The Solar system itself is highly unusual and will get several points. We have large planets on the outer edges and small planets closer to the star, which is only seen in about 10% of cases. Most star systems have large planets closer to the star and smaller planets outwards.

5. Solar system part two, it is unusual for a solar system to feature both rocky planets and gas gigants. Most have one or the other type of the planet, but not both. Let’s say this is another 10%, it’s probably lower but let’s put it at 10%.

6. Solar system part three, about 85% of star systems have more than one star, 15% have one star. For type G that’s a bit higher, with 56% and we can’t explain this yet. Let’s call this one 50%.

7. Solar system part four, we’re located in an unusually calm part of the galaxy. Most places have been variously zapped with X-ray bursts, supernovae or came across various other types of other cosmic horrors that would have ended any nascent life with prejudice. Let’s put this one at 10% of the galaxy being as calm as our bit, though it could be considerably less.

If you want to count the zeroes, we’re at approximately 1 in 100 billion at this point, certainly below 1 in 10 billion. Milky way has approximately 400 billion stars. Just accounting for these factors, then adding the “chance to develop life” in and some of the other stuff present in the Drake equation, pushes the probability of advanced, spacefaring civilization forming life being present in the Milky Way, to 1 planet or less. It’s probably a lot less, we rounded plenty of those estimates upwards, because it honestly didn’t matter.

Earth is rare. We know enough to state that with some certainty. We don’t know what other solutions to the Fermi paradox are also valid, but we know enough to state Earth and Solar system being total weirdos is one of them. They might well be unique to the Milky Way and possibly even rarer than that, there’s no way to know for sure.

Demand for observing time on Webb outpaces supply by a factor of nine. //

More than 600 scientists will review the proposals and select the most promising ones for time on Webb. The largest share of proposals would involve observing "high-redshift" galaxies among the first generation of galaxies that formed after the Big Bang. Galaxies this old and distant have their light stretched to longer wavelengths due to the expansion of the Universe. Research involving exoplanet atmospheres and stars and stellar populations were the second- and third-most popular science categories in this cycle.

The James Webb Space Telescope is the most powerful telescope ever put into space. As such, its helping usher in a new era of astrophysics. Astronomers can now study farther, earlier galaxies than ever before. //

As they peer into the deep, distant history of the universe, scientists are shocked to find galaxies showed in our cosmic history much sooner than scientists ever expected.

What galaxies forming earlier than scientists thought possible means for physics
Short Wave
What galaxies forming earlier than scientists thought possible means for physics
It's a galactic controversy that has astronomers around the world excited—and puzzled.

So what is it about these galaxies that is getting astronomers worked up? Not only is JWST finding galaxies forming 200-500 million years after the Big Bang, but also that they are bigger and brighter than astronomers expected. //

But much of the modeling astronomers have done up to this point has led them to believe that there wasn't enough time for galaxies to get this massive in so little time. //

In an attempt to explain the shockingly bright, highly structured—and possibly quite massive—galaxies existing so early in the timeline of the universe, a researcher has posited that the universe is roughly twice as old as previously believed. They push the age of the universe from a spry 13.8 billion years old to roughly 26.7 billion years old. //

"I think in science, if you already have a model that's simpler than that, you should stick to it—unless you have extraordinary evidence to do otherwise."

Moreno also cautions people against quickly jumping on this supposition that the universe is twice as old as previously thought. If it were true, scientists would be able to prove it through the direct observation of stars and galaxies that are older than 13.8 billion years old—the current accepted age of the universe.

No such evidence has been found.

Several types of astronomy would benefit. The most obvious is radio astronomy, which can be conducted from the side of the Moon that always faces away from Earth—the far side.

The lunar far side is permanently shielded from the radio signals generated by humans on Earth. During the lunar night, it is also protected from the Sun. These characteristics make it probably the most “radio-quiet” location in the whole solar system, as no other planet or moon has a side that permanently faces away from the Earth. It is, therefore, ideally suited for radio astronomy. //

Radio waves with wavelengths longer than about 15 m are blocked by Earth’s ionosphere. But radio waves at these wavelengths reach the Moon’s surface unimpeded. For astronomy, this is the last unexplored region of the electromagnetic spectrum, and it is best studied from the lunar far side.

Observations of the cosmos at these wavelengths come under the umbrella of “low-frequency radio astronomy.” These wavelengths are uniquely able to probe the structure of the early Universe, especially the cosmic “dark ages”—an era before the first galaxies formed.

At that time, most of the matter in the Universe, excluding the mysterious dark matter, was in the form of neutral hydrogen atoms. These emit and absorb radiation with a characteristic wavelength of 21 cm. Radio astronomers have been using this property to study hydrogen clouds in our own galaxy—the Milky Way—since the 1950s.

Because the Universe is constantly expanding, the 21 cm signal generated by hydrogen in the early Universe has been shifted to much longer wavelengths. As a result, hydrogen from the cosmic “dark ages” will appear to us with wavelengths greater than 10 m. The lunar far side may be the only place where we can study this. //

The Moon also offers opportunities for other types of astronomy as well. Astronomers have lots of experience with optical and infrared telescopes operating in free space, such as the Hubble telescope and JWST. However, the stability of the lunar surface may confer advantages for these types of instruments.

Moreover, there are craters at the lunar poles that receive no sunlight. Telescopes that observe the Universe at infrared wavelengths are very sensitive to heat and therefore have to operate at low temperatures. JWST, for example, needs a huge sun shield to protect it from the sun’s rays. On the Moon, a natural crater rim could provide this shielding for free.

This is a short-term forecast of the location and intensity of the aurora. This product is based on the OVATION model and provides a 30 to 90 minute forecast of the location and intensity of the aurora. The forecast lead time is the time it takes for the solar wind to travel from the L1 observation point to Earth.

Rocky debris caused by a NASA mission could create the first human-made meteor shower.

In Sept. 2022, NASA’s Double Asteroids Redirect Test (DART) intentionally collided with a tiny moonlet named Dimorphos, which orbited the asteroid Didymos, to test its asteroid deflection technology.

Scientists believe the crash produced over 2 million pounds of rocks and dust — and a new study suggests fragments of Dimorphos could land around Earth and Mars in 10 to 30 years, and the meteor showers could last for up to a century.

A sharp decline in sunspot activity in the 17th century has long puzzled astronomers. //

We realized that this [Kepler's] sunspot drawing should be able to tell us the location of the sunspot and indicate the solar cycle phase in 1607 as long as we managed to narrow down the observation point and time and reconstruct the tilt of the heliographic coordinates—meaning the positions of features on the Sun's surface—at that point in time.” //

German astronomer Gustav Spörer noted the steep decline in 1887 and 1889 papers, and his British colleagues, Edward and Annie Maunder, expanded on that work to study how the latitudes of sunspots changed over time. That period became known as the "Maunder Minimum." Spörer also came up with "Spörer's law," which holds that spots at the start of a cycle appear at higher latitudes in the Sun's northern hemisphere, moving to successively lower latitudes in the southern hemisphere as the cycle runs its course until a new cycle of sunspots begins in the higher latitudes.

But precisely how the solar cycle transitioned to the Maunder Minimum has been far from clear. //

"It is fascinating to see historical figures’ legacy records convey crucial scientific implications to modern scientists even centuries later," said co-author Sabrina Bechet of the Royal Observatory of Belgium. "I doubt if they could have imagined their records would benefit the scientific community much later, well after their deaths. We still have a lot to learn from these historical figures, apart from the history of science itself. In the case of Kepler, we are standing on the shoulders of a scientific giant."

Perseid meteors will streak through Earth’s atmosphere starting in mid-July. A first quarter moon won’t interfere with the shower’s peak on the mornings of August 11, 12 and 13.

It is about 3,000 light-years from Earth, but it can be witnessed with the naked eye. //

NASA predicts a nova will occur sometime this summer, about 3,000 light-years from Earth, but it can be witnessed with the naked eye.

The nova reoccurs once every 80 years. //

The nova should happen in a dark spot among the seven stars of Corona Borealis, known as the Northern Crown.

The dark spot contains “two stars that are bound to and in orbit around each other,” known as T Coronae Borealis or T CrB. NASA nicknamed it the Blaze Star:

Scientists carried out a survey of five million distant solar systems with the help of 'neural network' algorithms and it took an interesting turn when they found nearly 60 stars surrounded by what appeared as "giant alien power plants."

Among the 60 stars, seven of them - which were M-dwarf stars and ranged between 60 per cent and 8 per cent the size of the Sun - were seen releasing high infrared 'heat signatures,' as per the astronomers. //

While these structures are named for Freeman Dyson, a physicist and mathematician who proposed the building of a Dyson sphere to contain and capture all of a star's energy output, the concept actually goes back to a 1937 novel, Star Maker, by author Olaf Stapledon.

But as far as this study actually having detected such structures? Color me skeptical. //

What isn't said is what other explanations might cause these mid-infrared emissions; while I'm a biologist and not a cosmologist, it seems to me that a G-sequence star like our sun, were it to be surrounded by a cloud (or clouds) of gas or dust, may well also emit such an IR signature. And that's a lot more likely than an alien civilization that would by necessity be thousands, or millions of years ahead of us, technologically. //

Cliff-Hanger
3 hours ago
Ward, I'm a little disappointed. Dyson structures mentioned and not one bad pun about vacuum cleaners sucking the energy out of the stars.

Slowing down an asteroid by just one-tenth of a second makes all the difference.

This graph shows the number of sunspots seen each year for 400 years (from 1600 to 2000). There were almost no sunspots during the Maunder Minimum. During the Dalton Minimum, there were fewer sunspots than normal. //

The first written record of sunspots was made by Chinese astronomers around 800 B.C. Court astrologers in ancient China and Korea, who believed sunspots foretold important events, kept records off and on of sunspots for hundred of years. An English monk named John of Worcester made the first drawing of sunspots in December 1128. //

It would appear that sunspots not only have a connection to geomagnetic activity at Earth, but they play a role in climate change as well. In the last thousands of years, there have been many periods where there were not many sunspots found on the Sun. The most famous is a period from about 1645 to 1715, called the Maunder Minimum. This period corresponds to the middle of a series of exceptionally cold winters throughout Europe known as the Little Ice Age. Scientists still debate whether decreased solar activity helped cause the Little Ice Age, or if the cold snap happen to occur around the same time as the Maunder Minimum. In contrast, a period called the Medieval Maximum, which lasted from 1100 to 1250, apparently had higher levels of sunspots and associated solar activity. This time coincides (at least partially) with a period of warmer climates on Earth called the Medieval Warm Period. Sunspot counts have been higher than usual since around 1900, which has led some scientists to call the time we are in now the Modern Maximum.

Good morning. It's May 1, and today's photo is ridiculously awesome. Taken by the James Webb Space Telescope, it features the sharpest infrared image of the Horsehead Nebula captured to date—it is so zoomed in we can only see the mane. Even so, the image covers an area that is nearly one light-year across, or about 7.6 trillion km.

The Horsehead Nebula is fairly close to Earth, as these things go, about 1,300 light-years. So, it is within our galaxy. In addition to the prominent star at the top of the image and a handful of other stars with six diffraction spikes, the rest of the objects in this image are distant galaxies.

In astronomy, a planetary transit is when a planet closer to the Sun passes in front of the Sun's disc as seen from a more distant planet. From the Earth, transits of Mercury and Venus are visible; recently, observers were treated to these spectacles in back-to-back years: 2003 and 2004.

In the run-up to the 2004 transit of Venus, I became obsessed with one of those silly questions which, once they sink their claws into one's mind, won't go away without being answered yes or no. Is there ever a simultaneous transit of Mercury and Venus visible from the Earth?

The naïve answer is, “Of course not (you idiot)! Transits can occur only when inferior conjunction with the inner planet coincides with its crossing the ecliptic. Transits of Venus always occur in June and December, transits of Mercury in May and November, and thus a simultaneous transit can never happen.”

But this doesn't take into account the evolution of planetary orbits over time. Analytical planetary theories such as VSOP87 are useless beyond the period for which they are fit (say, −4000 to +8000 years Gregorian). To go beyond that, you need to do full-up numerical integration of the motion of the Sun and planets.

Well, that's what computers are for, isn't it? So, I found a high-precision numerical integration code for the Solar System written by Steve Moshier, built a back-end to search for transits, and set it looking for this extraordinarily rare event. Since I didn't want to burn months of computing time with nothing to show for it, I decided to prepare a canon of all Solar System transits (excluding marginal graze events) visible in the time interval I chose, namely a quarter million years centred on the start of the so-called “Common Era”. Here it is.

There are about 200 billion stars in our Milky Way galaxy. Over the next million years our descendents will spread among the stars in an exponential explosion of life, remaking the galaxy as surely as life has remolded Earth in its own image. //

Imagine the variety of worlds and wealth of living species flourishing upon them! Water worlds, desert planets, mountains that reach above the sky—every habitat imagined in science fiction will become real, and many more yet to spring from the imagination of world-makers born half a million years from now.

Terranova is a highly premature anticipation of this exhilarating milestone in the endless adventure of life and intelligence. Every day around 11 a.m. Universal Time a new planet is created using random parameters, and an image of it, as seen from the bridge from your approaching starship, is produced.

“If they existed, they would be here”, said Fermi. So where are they? Nowhere in evidence. Intelligent beings with technologies advanced millions of years beyond our own, spread to the far ends of the galaxy, should not be difficult to detect. We already possess the means to detect even primitive technological civilisations like our own at a distance of hundreds of light years.

If they existed, they—the first intelligent species to expand outward among the stars—would be here. And since we look around and see nobody but ourselves, then it is only reasonable to conclude, “We are here, so we are them.”