Category Archives: NASA

Astronomy, Black Hole, Cosmology, Dark Matter, NASA, Planets

Ten amazing space discoveries in 2024.

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The Early Universe is Running out of Supermassive Black holes.

As the Webb Space Telescope continues to find supermassive blackholes (SMBH) in the time after the Dark Ages, there has been a significant down turn in their masses. Now the most common SMBHs earlier than one billion years ABB are about 4 million solar masses – about the same mass as Sgr A* in our Milky Way.  At 700 million years ABB, Webb found a SMBH with 40 million solar masses. GN-z11 at 420 million years ABB has an estimated mass of 2 million suns. LID-568 (See NASA artwork above) has a mass of 10 million suns at an age 1.5 billion years ABB. ZS7 consists of two merging SMBHs each with a mass of about 50 million suns at an age of about 740 million years ABB. So, Webb is now giving us a glimpse of black hole mergers and rapid growth long before we reach the billion-sun masses of todays SMBHs.

Cosmic Gravity Wave Background

Teams of scientists worldwide have reported the discovery of the “low pitch hum” of these cosmic ripples flowing through the Milky Way. The detected signal is compelling evidence and consistent with theoretical expectations of gravity wave pulses from millions of distant binary hole mergers, where these black holes are of the SMBH variety. The artwork above is provided by NASA. [UC Berkeley News]

DESI survey of 6 million galaxies validates Big Bang

Researchers used the Dark Energy Spectroscopic Instrument (DESI) to map how nearly 6 million galaxies cluster across 11 billion years of cosmic history as shown in the image above (Credit: D. Schlegel/Berkeley Lab using data from DESI). Their observations line up with what Einstein’s theory of general relativity predicts. Looking at galaxies and how they cluster across time reveals the growth of cosmic structure, which lets DESI test theories of modified gravity – an alternative explanation for our universe’s accelerating expansion. DESI researchers found that the way galaxies cluster is consistent with our standard model of gravity and the predictions from Einstein’s theory of general relativity. There is even a suggestion in the data that Dark Energy is weakening as the universe ages over the last 11 billion years. This has huge implications for modeling the future of the universe. [News from Berkeley Lab]

Supersymmetry searches still come up empty-handed

Before the beginning of the Large Hadron Collider data taking, supersymmetry (SUSY)  was seen as a single answer to many unresolved open questions of the Standard Model. The LHC ATLAS research program has first quickly excluded most of the simplest SUSY configurations, then moved to a detailed work targeting many signatures, not necessarily favored by a theoretical prejudice. The lack of an identified SUSY signal so far at the massive ATLAS detector shown above (Credit: ATLAS Experiment © 2022 CERN) is certainly a disappointing and possibly somewhat surprising outcome to many scientists. A lot of theoretical effort into String theory and the search for a quantum theory of gravity hinges on going beyond the so-called Standard Model, and supersymmetry is a key mathematical ingredient to many of these simpler extensions. [LHC-ATLAS Consortium]

Dark Matter searches still find no candidate particles

After 40 years of searching for dark matter candidate particles, the currently most popular assumption for the nature of DM still is that of a (new) particle, even though the jury is not entirely out on whether the present observations of DM are due to a particle (or wave-like behavior at very low masses) or due to our limited understanding of the gravitational force at large scales. The figure above shows the current list of candidate particles being considered (Credit: CERN/G. Bertone and T. M. P. Tait) Despite its success, the Standard Model of particle physics (SM) in its present form (6 quarks, 6 leptons, 1 Higgs boson, plus the 12 quanta for the three non-gravity forces) is not able to offer an explanation for dark matter. It offers no known particle that can play that role. The LHC experiments, meanwhile, have by now completed and published all their main DM search analyses for the Run-2 data taken before 2016. No evidence as yet has been found for signals of the production of dark matter or dark sector particles. Dark matter, as a particle representing some 25% of all gravitating ‘stuff’ in the universe, remains one of the biggest puzzles in physics today.

Origin of the solar wind discovered

After several decades of theoretical speculation, solar physicists are now certain that they have discovered how our sun produces the interplanetary wind of matter that streams out of its corona at speeds of over 200 km/s. In 2024, the ESA-led Solar Orbiter spacecraft made the first ever connection between measurements of the solar wind around a spacecraft to high-resolution images of the Sun’s surface at a close distance. The spacecraft passed through the magnetic field connected to the edge of a coronal hole complex. This let the team watch the way the solar wind changed its speed – from fast to slow or vice versa – and other properties, confirming that they were looking at the correct region. In the end, they got a perfect combination of both types of features together. The image above (Credit:ESA & NASA/Solar Orbiter/EUI Team; acknowledgement: Lakshmi Pradeep Chitta, Max Planck Institute for Solar System Research) taken by the ESA/NASA Solar Orbiter spacecraft shows a ‘coronal hole’ near the Sun’s south pole. Subsequent analysis revealed many tiny jets of plasma being released into the corona and solar wind during the observation. 

The origin of the springtime, dinosaur-killer asteroid

According to a recent article published in Nature magazine, the object that smashed into Earth and kick-started the extinction that wiped out almost all dinosaurs 66 million years ago was an asteroid that originally formed beyond the orbit of Jupiter, according to geochemical evidence from the impact site in Chicxulub, Mexico. Comparisons between the chemical record left behind by the strike 66 million years ago and known meteorite samples suggest that the Cretaceous asteroid was a carbonaceous chondrite. This type of asteroid is one of the oldest known, having formed billions of years ago in the early solar system. As these chondrites can only come from asteroids found beyond Jupiter, it suggests that the asteroid must have had its origins there too. Some of the chondritic spherules got into the gills of dying fish, fossils of which have been used to reveal that  the asteroid impacted during the springtime in the northern hemisphere. This is possible to know based on where the lines of growth in the fish’s bones stop, which can be read somewhat like rings in a tree trunk.

Current round-up of fireball detections worldwide

The most recent world map of detected fireballs from 1988 to 2024 detected with a variety of sensors (optical, infrasound, etc) reveals that fireballs delivering less than 30 kilotons-equivalent TNT upon atmospheric detonation are uniformly spread around Earth’s surface. In 2019 it was determined that the Geostationary Lightning Mapper (GLM) instruments on GOES weather satellites can detect fireballs and bolides. This largely removes much of the observer-bias from the detections irrespective of geographic latitude. The bright red dot is the 2013 Chelyabinsk Meteor fireball and impact. (Credit: NASA/CNEOS/JPL)

NASA spacecraft detects subterranean Martian water

Using seismic activity to probe the interior of Mars, geophysicists have found evidence for a large underground reservoir of liquid water — enough to fill oceans on the planet’s surface. The data from NASA’s Insight lander (2018-2022) allowed the scientists to estimate that the amount of groundwater could cover the entire planet to a depth of between 1 and 2 kilometers, or about a mile. While that’s good news for those tracking the fate of water on the planet after its oceans disappeared more than 3 billion years ago, the reservoir won’t be of much use to anyone trying to tap into it to supply a future Mars colony. It’s located in tiny cracks and pores in rock in the middle of the Martian crust, between 11.5 and 20 kilometers (7 to 13 miles) below the surface. Even on Earth, drilling that deep would be a challenge. [UC Berkeley News].

Organized magnetic fields in Sgr A* black hole accretion disk

A new image from the Event Horizon Telescope (EHT) collaboration has uncovered strong and organized magnetic fields spiraling from the edge of the supermassive black hole Sagittarius A* (Sgr A*). Seen in polarized light for the first time, this new view of the monster lurking at the heart of the Milky Way Galaxy has revealed a magnetic field structure strikingly similar to that of the black hole at the center of the M87 galaxy, suggesting that strong magnetic fields may be common to all black holes. This similarity also hints toward a hidden jet in Sgr A*.Scientists unveiled the first image of Sgr A*— which is approximately 27,000 light-years away from Earth— in 2022, revealing that while the Milky Way’s supermassive black hole is more than a thousand times smaller and less massive than M87’s, it looks remarkably similar. This made scientists wonder whether the two shared common traits outside of their looks. To find out, the team decided to study Sgr A* in polarized light. Previous studies of light around M87* revealed that the magnetic fields around the black hole giant allowed it to launch powerful jets of material back into the surrounding environment. Building on this work, the new images have revealed that the same may be true for Sgr A*. [Credit EHT Collaboration]

Astronomy, Earth, NASA, Physics

How fast does a rocket have to travel to leave the atmosphere?

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The GRACE Follow-On spacecraft launched into orbit in May 2018. Credit: NASA/Bill Ingalls

The orbit insertion velocity near the Earth’s surface is practically the same as the Earth escape velocity of 11.2 kilometers per second, or 25,805 miles per hour.

Even at an altitude of 200 kilometers, a rocket is still inside the outer reaches of the Earth’s atmosphere. To really leave the atmosphere it probably has to get to a distance of 27,000 miles near the ‘geosynchronous’ limit. There is no sharp boundary to Earth’s atmosphere. It just decreases steadily in density until it eventually matches the density of the interplanetary medium. Here is an image that shows the extent of the geocorona, whose density is so low that it has no effect on spacecraft but qualifies as part of Earth’s atmosphere nonetheless. It was taken by NASA astronaut John Young using an ultraviolet camera on Apollo 16.

NASA, Space Travel

An Old Era Ends-A New One is Born-Updated

As the international rush to get to the moon ramps up in the next few years, it is worth noting that, just as we are losing the World War II generation, we are also losing NASA’s early astronaut corps who made the 1960s and 1970’s space exploration possible.

Often called the most significant photo from space in human history, the famous “Earthrise” photo taken by Apollo 8 astronauts on Dec. 24, 1968 never fails to cause an emotional response. 

The Mercury, Gemini and Apollo astronauts are legends who made our current travel to the moon far less of a challenge 50 years later than it would otherwise have been. Since these missions completed their historic work, we have been able to mull over many scenarios for how to do it ‘right’ the next time, and so here we are. We have learned from our successes in science and engineering, but we have also learned from our failure of political nerve to go beyond the gauntlet thrown down by Apollo 17. Now we are in the midst of what appears to be a new Space Race, this time between the open societies of the ‘west’ and the closed and secretive society of China. Meanwhile, amidst this political hubris, the ranks of the Old Guard astronauts continue to thin out each year.

Project Mercury

The first group of astronauts to pass, were the original Project Mercury astronauts at the pionering, and very risky, dawn of NASA (1958-1963): Scott Carpenter, Gordon Cooper, John Glenn, Virgil Grisson, Walter Schirra, Alan Shepard and Donald Slayton. With the passing of John Glen in 2016 at the age of 95, we lost irretrivably our connection to the trials and tribulations of sitting in a ‘tin can’ as big as a telephone booth and eating food out of toothpaste tubes. These were the incredably brave men who sat on top of rockets that had only been tested a handful of times without blowing up!

John Glenn entering the Friendship 7 Mercury capsule on top of the Redstone rocket,

But more than that, these were the faces of NASA that we saw in the news media who made space travel a household word in the early-1960s. This was a HUGE transition in social consciousness because prior to Project Mercury, space travel was pure science fiction. We were a Nation obsessed by the prospects of nuclear war and Soviet spies lurking around every street corner. The adventures of the Mercury astronauts let hundreds of millions of people take a mental vacation and think about more hopeful ties to come. That plus the advent of the Jetsons TV series!

The 14 ‘Group 3’ astronauts selected in 1963 for the Gemini and Apollo manned programs

The second cohort of astronauts were those that flew with Project Gemini between 1963 and 1966. There were ten crewed missions and 16 astronauts, who conducted space walks, dockings and tested out technology and protocols for the Apollo program. Many of them went on to fly in Project Apollo having earned their ‘creds’ with Gemini.

The photo above shows, seated left to right, Edwin Aldrin (33), William Anders (30), Charles Bassett (32), Alan Bean (31), Eugene Cernan (29), and Roger Chaffee (28). Standing left to right are Michael Collins (33), Walter Cunningham (31), Donn Eisele (33), Theodore Freeman (33), Richard Gordon (34), Russell Schweickart (28), David Scott (31) and Clifton Williams (31). Additional astronauts were selected for Gemini: Frank Borman (35), Jim Lovell (35), Thomas Stafford (33), John Young (34), Neil Armstrong (33), and Pete Conrad (33). The ages of this group in 1963 spanned 29 to 35.

Whenever I look at this photo, I see these astronauts as being 10 years older than their actual age. I was a teenager during this time and anyone older than 25 or 30 looked pretty old to me. I guess for these astronauts, a military life, and the dress styles of the narrow-tie, conservative, early-60s does that to you.

NASA Astronaut Edward White floats in zero gravity of space northeast of Hawaii, on June 3, 1965, during the flight of Gemini IV.

At the present time, December 2024, the only survivors of the Mercury and Gemini groups are Edwin Aldrin (94), Russell Schweickart (89) and David Scott (92).

Finally, we have the Program Apollo astronauts. They were actually drawn from the Project Gemini group, but because of the premature deaths of Roger Chaffee, Ed White, Charles Bassett, and Theodore Freeman, additional astronauts were added to this project: Charles Duke, Harrison Schmitt, Ken Mattingly, Fred Haise, Wally Schirra, Edgar Mitchell, Jack Swigert, James Irwin, Alfred Wordon, James McDivitt, Ronald Evans, and Stuart Roosa.

50th Anniversary, 2019: From left to right: Charlie Duke (Apollo 16), Buzz Aldrin (Apollo 11), Walter Cunningham (Apollo 7), Al Worden (Apollo 15), Rusty Schweickart (Apollo 9), Harrison Schmitt (Apollo 17), Michael Collins (Apollo 11) and Fred Haise (Apollo 13). 
Felix Kunze/The Explorers Club

Each Apollo mission had three astronauts. Two would take the LEM to the surface for a walk-about, while the third astronaut remained behind in the Command Module. A total of 12 Apollo astronauts actually walked on the moon between Apollo 11 and 17: Neil Armstrong, Buzz Aldrin, Pete Conrad, Alan Bean, Alan Shepard, Edgar Mitchell, David Scott, James Irwin, John Young, Charles Duke, Eugene Cernan and Harrison Schmitt. Of these, the survivors by January, 2023 are Buzz Aldrin (92), David Scott (90), Charles Duke (87) and Harrison Schmitt (87).

An excellent view of the Lunar Excursion Module (LEM) “Orion” and Lunar Roving Vehicle (LRV), as photographed by astronaut Charles M. Duke Jr., lunar module pilot, during the first Apollo 16 extravehicular activity (EVA) at the Descartes landing site.

So, the surveying astronauts in December 2024 from the Mercury, Gemini and Apollo programs are, in order of age:

Buzz Aldrin (94: Gemini 12, Apollo 11),

David Scott (92: Gemini 8, Apollo 9, Apollo 15),

Fred Haise (91: Apollo 13),

Russell Schweickart (89: Apollo 9),

Charles Duke (89: Apollo 16)

Harrison Schmitt (89: Apollo 17).

Apollo 17 astronaut Harrison Schmitt on the moon.

We are entering something of a race against time for these survivors to be present for the launch of Artemus III. Artemis III is planned as the first crewed Moon landing mission of the Artemis program. Scheduled for launch in 2026, Artemis III is planned to be the second crewed Artemis mission and the first crewed lunar landing since Apollo 17 in 1972. Buzz Aldrin (92: Gemini 12, Apollo 11) was one of the first astronauts to set foot on the lunar surface, while Harrison Schmitt of Apollo 17 was one of the last. With Buzz Aldrin and David Scott, we even have survivors from the Gemini Program who laid the groundwork for EVAs (Gemini 12) and docking maneuvers (Gemini 8).

The odds are pretty good that many of these six Old Guard astronauts will still be with us to see the Artimus III lunar lander called Starship HLS reach the lunar surface, and oh what a celebration it will be at NASA!

Astronomy, NASA

The Next Sunspot Cycle

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Forecasters are already starting to make predictions for what might be in store as our sun winds-down its current sunspot cycle (Number 24) in a few years. Are we in for a very intense cycle of solar activity, or the beginning of a century-long absence of sunspots and a rise in colder climates?

Figure showing the sunspot counts for the past few cycles. (Credit:www.solen.info)

Ever since Samuel Schwabe discovered the 11-year ebb and flow of sunspots on the sun in 1843, predicting when the next sunspot cycle will appear, and how strong it will be, has been a cottage industry among scientists and non-scientists alike. For solar physicists, the sunspot cycle is a major indicator of how the sun’s magnetic field is generated, and the evolution of various patterns of plasma circulation near the solar surface and interior. Getting these forecasts bang-on would be proof that we indeed have a ‘deep’ understanding of how the sun works that is a major step beyond just knowing it is a massive sphere of plasma heated by thermonuclear fusion in its core.

So how are we doing?

For over a century, scientists have scrutinized the shapes of dozens of individual sunspot cycles to glean features that could be used for predicting the circumstances of the next one. Basically, we know that 11-years is an average and some cycles are as short as 9 years or as long as 14. The number of sunspots during the peak year, called sunspot maximum, can vary from as few as 50 to as many as 260. The speed with which sunspot numbers rise to a maximum can be as long as 80 months for weaker sunspot cycles, and as short as 40 months for the stronger cycles. All of these features, and many other statistical rules-of-thumb, lead to predictive schemes of one kind or another, but they generally fail to produce accurate and detailed forecasts of the ‘next’ sunspot cycle.

Prior to the current sunspot cycle (Number 24), which spans the years 2008-2019, NASA astronomer Dean Pesnell collected 105 forecasts for Cycle 24 . For something as simple as how many sunspots would be present during the peak year, the predictions varied from as few as 40 to as many as 175 with an average of 106 +/-31. The actual number at the 2014 peak was 116. Most of the predictions were based on little more than extrapolating statistical patterns in older data. What we really want are forecasts that are based upon the actual physics of sunspot formation, not statistics. The most promising physics-based models we have today actually follow magnetic processes on the surface of the sun and below and are called Flux Transport Dynamo models.

Solar polar magnetic field trends (Credit: Wilcox Solar Observatory)

The sun’s magnetic field is much more fluid than the magnetic field of a toy bar magnet. Thanks to the revolutionary work by helioseismologists using the SOHO spacecraft and the ground-based GONG program, we can now see below the turbulent surface of the sun. There are vast rivers of plasma wider than a dozen Earths, which wrap around the sun from east to west. There is also a flow pattern that runs north and south from the equator to each pole. This meridional current is caused by giant convection cells below the solar surface and acts like a conveyor belt for the surface magnetic fields in each hemisphere. The sun’s north and south magnetic fields can be thought of as waves of magnetism that flow at about 60 feet/second from the equator at sunspot maximum to the poles at sunspot minimum, and back again to the equator at the base of the convection cell. At sunspot minimum they are equal and opposite in intensity at the poles, but at sunspot maximum they vanish at the poles and combine and cancel at the sun’s equator. The difference in the polar waves during sunspot minimum seems to predict how strong the next sunspot maximum will be about 6 years later as the current returns the field to the equator at the peak of the next cycle. V.V Zharkova at Northumbria University in the UK uses this to predict that Cycle 25 might continue the declining trend of polar field decrease seen in the last three sunspot cycles, and be even weaker than Cycle 24 with far fewer than 100 spots. However, a recent paper by NASA solar physicists David Hathaway and Lisa Upton  re-assessed the trends in the polar fields and predict that the average strength of the polar fields near the end of Cycle 24 will be similar to that measured near the end of Cycle 23, indicating that Cycle 25 will be similar in strength to the current cycle.

But some studies such as those by Matthew Penn and William Livingston at the National Solar Observatory seem to suggest that  sunspot magnetic field strengths have been declining since about 2000 and are already close to the minimum needed to sustain sunspots on the solar surface.  By Cycle 25 or 26, magnetic fields may be too weak to punch through the solar surface and form recognizable sunspots at all, spelling the end of the sunspot cycle phenomenon, and the start of another Maunder Minimum cooling period perhaps lasting until 2100. A quick GOOGLE search will turn up a variety of pages claiming that a new ‘Maunder Minimum’ and mini-Ice Age are just around the corner! An interesting on-the-spot assessment of these disturbing predictions was offered back in 2011 by NASA solar physicist C. Alex Young, concluding from the published evidence that these conclusions were probably ‘Much Ado about Nothing’.

What can we bank on?

The weight of history is a compelling guide, which teaches us that tomorrow will be very much like yesterday. Statistically speaking, the current Cycle 24 is scheduled to draw to a close about 11 years after the previous sunspot minimum in January 2008, which means sometime in 2019. You can eyeball the figure at the top of this blog and see that that is about right. We entered the Cycle 24 sunspot minimum period in 2016 because in February and June, we already had two spot-free days. As the number of spot-free days continues to increase in 2017-2018, we will start seeing the new sunspots of Cycle 25 appear sometime in late-2019. Sunspot maximum is likely to occur in 2024, with most forecasts predicting about half as many sunspots as in Cycle 24.

None of the current forecasts suggest Cycle 25 will be entirely absent. A few forecasts even hold out some hope that a sunspot maximum equal to or greater than Cycle 24 which was near 140 is possible, while others place the peak closer to 60 in 2025.

It seems to be a pretty sure bet that there will be yet-another sunspot cycle to follow the current one. If you are an aurora watcher, 2022-2027 would be the best years to go hunting for them. If you are a satellite operator or astronaut, this next cycle may be even less hostile than Cycle 24 was, or at least no worse!

In any event, solar cycle prediction will be a rising challenge in the next few years as scientists pursue the Holy Grail of creating a reliable theory of why the sun even has such cycles in the first place!

Check back here on Friday, February 17 for my next blog!