(July 2, 2026)
Faced with observations of early black holes and galaxies that werenât expected to exist, scientists have come up with a wealth of new theories to explain them. Now they just need to figure out which ones are true.
Archiv: Interstellarer Raum / interstellares Medium / interstellar space / interstellar medium
NASAâs IMAP Begins Primary Science Mission
(February 2, 2026)
NASAâs IMAP (Interstellar Mapping and Acceleration Probe) began its two-year primary science mission on Feb. 1 to explore and map the boundaries of our heliosphere â the protective bubble created by the solar wind that encapsulates our solar system.
The mission, which launched on Sept. 24, 2025, relies on 10 scientific instruments to chart a comprehensive picture of whatâs roiling in space, from high-energy particles originating at the Sun, to magnetic fields in interplanetary space, to dust left from exploded stars in interstellar space.
NASA begins mission to map the boundaries of our heliosphere
(February 3, 2026)
A NASA probe has started its mission to map the heliosphere, which is a huge protective bubble around the solar system that was created by the sun, the space agency announced on Monday.
The space agency‘s Interstellar Mapping and Acceleration Probe, or IMAP, is expected to continue its mission for two years, using scientific instruments to chart the boundaries of the heliosphere and what‘s going on inside of it.
The probe is focusing on high-energy particles bursting from the surface of the sun, the magnetic fields that form in the spaces between planets, and the dust left behind by collapsed stars farther out in the galaxy.
Voyager 1 Trajectory through the Solar System
Aug 31, 2017
This visualization tracks the trajectory of the Voyager 1 spacecraft through the solar system. Launched on September 5, 1977, it was one of two spacecraft sent to visit the giant planets of the outer solar system. Voyager 1 flew by Jupiter and Saturn before being directed out of the solar system.
To fit the 40 year history of the mission into a short visualization, the pacing of time accelerates through most of the movie, starting at about 5 days per second at the beginning and speeding up to about 11 months per second after the planet flybys are past.
The termination shock and heliopause are the ‚boundaries‘ created when the plasma between the stars interacts with the plasma flowing outward from the Sun.
Animation: Heliosphere
(March 9, 2022)
This complex environment surrounds the planets and ultimately has a crucial effect on the formation, evolution, and destiny of planetary systems. For one thing, our heliosphere acts as a giant shield, protecting the planets from galactic cosmic radiation. Earth is additionally shielded by its own magnetic field, the magnetosphere, which protects us not only from solar and cosmic particle radiation but also from erosion of the atmosphere by the solar wind. Planets without a shielding magnetic field, such as Mars and Venus, are exposed to such processes and have evolved differently.
NASA‘s studies of the heliosphere include research into: how the solar wind behaves near Earth; what causes and sustains magnetic and electric fields around other planets; how does the heliosphere interact with the interstellar medium; what do the boundaries of the heliosphere look like; what is the origin and evolution of the solar wind and the interstellar cosmic rays; and what contributes to the habitability of exoplanets.
More than a planetary fender-bender: New study finds Earth collided with dense interstellar cloud, possibly affecting life on planet
(June 10, 2024)
Evidence of a long-ago collision involving the Earth was there in the form of specific radioactive isotopes deposited across the Earth and Moon. There were, however, skeptics.
But now researchers have tracked the sunâs path through the Milky Way back to a crash 2 to 3 million years ago with a dense interstellar cloud. The event was so violent it appears to have collapsed the sunâs protective bubble around the solar system and possibly even affected life on Earth.
(…)
âWe donât often discuss the impact of astrophysics on Earth because the astronomical timescales are very long, and the human species emerged on Earth just a few million years ago,â Loeb said. âBut a few million years ago there was the potential for us to be passing through a very dense cloud. We didnât work out the biological implications, but itâs clear that if you shrink the heliosphere to within the orbit of the Earth around the sun, we are not protected anymore. It could have significant implications for life on Earth.â
11 Years Charting Edge of Solar System
Jun 11, 2020
Far, far beyond the orbits of the planets lie the hazy outlines of the magnetic bubble in space that we call home.
This is the heliosphere, the vast bubble that is generated by the Sunâs magnetic field and envelops all the planets. The borders of this cosmic bubble are not fixed. In response to the Sunâs gasps and sighs, they shrink and stretch over the years.
Now, for the first time, scientists have used an entire solar cycle of data from NASAâs IBEX spacecraft to study how the heliosphere changes over time. Solar cycles last roughly 11 years, as the Sun swings from seasons of high to low activity, and back to high again. With IBEXâs long record, scientists were eager to examine how the Sunâs mood swings play out at the edge of the heliosphere. The results show the shifting outer heliosphere in great detail, deftly sketch the heliosphereâs shape â a matter of debate in recent years, and hint at processes behind one of its most puzzling features. These findings, along with a newly fine-tuned data set, are published in The Astrophysical Journal Supplements on June 10, 2020.
NASA confirms Voyager spacecraft has encountered a âwall of fireâ at the edge of the Solar System
(November 6, 2025)
According to NASA, Voyager 1 has now encountered what researchers describe as a âwall of fire,â a zone where temperatures reach between 30,000 and 50,000 kelvin â roughly 30,000 degrees Celsius. The finding was made as part of ongoing efforts to understand the boundary separating our Solar System from interstellar space.
(…)
âAn observation made by Voyager 2 confirms a surprising result from Voyager 1: the magnetic field in the region just beyond the heliopause is parallel to the magnetic field inside the heliosphere,â NASA noted. With data from both spacecraft, scientists can now confirm that this alignment is not a coincidence but a defining characteristic of the boundary region.
Voyager 1 Trajectory through the Solar System
628,218 views Aug 31, 2017
This visualization tracks the trajectory of the Voyager 1 spacecraft through the solar system. Launched on September 5, 1977, it was one of two spacecraft sent to visit the giant planets of the outer solar system. Voyager 1 flew by Jupiter and Saturn before being directed out of the solar system.
To fit the 40 year history of the mission into a short visualization, the pacing of time accelerates through most of the movie, starting at about 5 days per second at the beginning and speeding up to about 11 months per second after the planet flybys are past.
The termination shock and heliopause are the ‚boundaries‘ created when the plasma between the stars interacts with the plasma flowing outward from the Sun.
NASAâs Voyager 1 set to become first human-made object to reach a full light-day distance from Earth in 2026
Launched in 1977, Voyager 1 has been cruising through space for nearly 47 years, traveling a mind-boggling distance of almost 16 billion miles from Earth. This journey has already broken recordsâit was the first spacecraft to cross the heliopause, the boundary where the Sunâs solar wind yields to interstellar space. Now, it is on course to reach a distance known as a light-day, meaning the distance that light travels in 24 hours.
Traveling at about 38,000 miles per hour, Voyager 1âs progress may seem slow compared to light speed, but it reveals the vast scales of cosmic distance. Radio signals sent from the spacecraft take nearly 23 hours to reach Earth, which offers a glimpse into the immense challenges of communicating across these astronomical expanses.
The Voyagers Are Still Exploring 40 Years Later
(Oct. 12, 2024)
From their unique vantage points â Voyager 1 in the northern hemisphere and Voyager 2 in the southern hemisphere â the spacecraft have already detected differences and asymmetries in the solar wind termination shock, where the wind abruptly slows as it approaches the heliopause. For example, Voyager 2 crossed the termination shock at a distance of about 83.7 AU in the southern hemisphere. (One AU, or astronomical unit, is equal to 150 (million) kilometers (93 million miles), the distance between Earth and the Sun.) Thatâs about 10 AU closer to the Sun than where Voyager 1 crossed the shock in the north. As shown in this diagram, Voyager 1 traveled through the compressed ânoseâ of the termination shock and Voyager 2 is expected to travel through the flank of the termination shock.
Voyager 1 Trajectory through the Solar System
628,218 views Aug 31, 2017
This visualization tracks the trajectory of the Voyager 1 spacecraft through the solar system. Launched on September 5, 1977, it was one of two spacecraft sent to visit the giant planets of the outer solar system. Voyager 1 flew by Jupiter and Saturn before being directed out of the solar system.
To fit the 40 year history of the mission into a short visualization, the pacing of time accelerates through most of the movie, starting at about 5 days per second at the beginning and speeding up to about 11 months per second after the planet flybys are past.
The termination shock and heliopause are the ‚boundaries‘ created when the plasma between the stars interacts with the plasma flowing outward from the Sun.
Our planet is in a space balloon, literally
(June 16, 2024)
But only two human-made objects have crossed the boundary of the solar system and entered interstellar space.
In 1977, NASA launched Voyager 1 and Voyager 2, equipped with tools to measure the magnetic fields and the particles it is directly passing through. After traveling for over three decades in space, they finally exited the outer layer of the heliosphereâheliopause in 2012 and 2018 respectively. They discovered that cosmic rays are about three times more intense outside the heliopause than deep inside the heliosphere.
#OTD in 2019, @NASA‘s #NewHorizons flew by Arrokoth, the farthest object ever explored by spacecraft. Arrokoth is about about 50 AU, or 4 billion miles from the Sun. New Horizons is ~56 AU from Earth and will join Voyagers 1 & 2 in interstellar space in the 2040s.
5 Spacecraft Are Leaving The Solar System. What Did They See In Their Journey?
Pioneer 10: Pioneer 10 was launched in 1972 to explore the planets of the solar system. It achieved the first flyby of Mars, the first trip through the asteroid belt, and Jupiter‘s first flyby. It was the first time NASA had used nuclear energy to power its spacecraft. So, after Pioneer 10 passed Jupiter in 1973, it still had ample energy to keep going. Initially planned for 21 months, it continued to communicate with Earth for a total of 30 years.
What Spacecraft Will Enter Interstellar Space Next?
(January 30, 2019)
This milestone â reaching interstellar space â can be considered leaving the solar system by a certain definition. Let‘s be clear about what that entails. In 1990, the New York Times reported that Pioneer was reported to leave the solar system when it flew past Neptune‘s orbit. That‘s not what Voyager 2‘s scientists used to make their determination, however. Instead, the more recent measurements consider the crossing of the sun‘s heliopause, the theoretical boundary to its heliosphere, to be the determining factor for entering interstellar space. The heliosphere is a bubble of charged particles created by and flowing past the sun. Scientists use it to mark where interstellar space begins.
Raumsonde âPioneer 10â 40 Jahre aus Sonnensystem heraus
Am 13. Juni 1983 durchflog âPioneer 10â die Umlaufbahn des Neptun und wurde so laut NASA zum ersten menschengemachten Raumschiff, das am weitestentfernten bekannten Planeten unseres Sonnensystems vorbeiflog. Neptun ist im Mittel etwa 4,5 Milliarden Kilometer von der Sonne entfernt.
Mit âPioneer 11â und den beiden âVoyagerâ-Sonden folgten spĂ€ter Ă€hnliche Missionen. âVoyager 1â ĂŒberholte âPioneer 10â schlieĂlich als am weitesten von der Erde entferntes menschengemachtes Objekt. Zum bisher letzten Mal schickte âPioneer 10â im JĂ€nner 2003 Daten, ein Kontaktversuch im MĂ€rz 2006 scheiterte.
The Shrinking of the Heliosphere Due to Reduced Solar Wind
(2010)
Abstract. The heliosphere is the space within which the solar wind dominates and the solar interplanetary magnetic field prevails. Its boundary is determined by the balance between stellar and solar winds. Owing to the present reduction in the solar wind pressure, one would expect that the stellar wind would push the heliosphere inward leading to its shrinkage. In this paper we calculate the extent of the heliosphere at different solar wind status.
Backward estimation of the extent of the heliosphere since 1890 is done. It is found that the heliosphere oscillated between 75 and 125 AU between 1890 –
2010. Most important is the forecast of the shrinkage and oscillations of the heliosphere and their implications on the earth. The shrinkage of the heliosphere would allow more invasions of cosmic rays to the earth and planets, increased cloud cover and a cooler Earth.
1 Introduction
The heliosphere is the cavity curved by the solar wind into the interstellar medium. Its extension is determined by the equality of the solar wind pressure and the stellar wind pressure. For this reason, we will first study past, present and future status of solar activity and then we will reflect this study into the heliosphere.
Sun‘s protective ‚bubble‘ is shrinking
(18.10.2008)
New data has revealed that the heliosphere, the protective shield of energy that surrounds our solar system, has weakened by 25 per cent over the past decade and is now at it lowest level since the space race began 50 years ago. (…)
„Around 90 per cent of the galactic cosmic radiation is deflected by our heliosphere, so the boundary protects us from this harsh galactic environment.“
The heliosphere is created by the solar wind, a combination of electrically charged particles and magnetic fields that emanate a more than a million miles an hour from the sun, meet the intergalactic gas that fills the gaps in space between solar systems.
A Unified Model for the Fan Region and the North Polar Spur: A bundle of filaments in the Local Galaxy
We present a simple, unified model that can explain two of the brightest, large-scale, diffuse, polarizedradio features in the sky, the North Polar Spur (NPS) and the Fan Region, along with several otherprominent loops. We suggest that they are long, magnetized, and parallel filamentary structures thatsurround the Local arm and/or Local Bubble, in which the Sun is embedded. We show this modelis consistent with the large number of observational studies on these regions, and is able to resolvean apparent contradiction in the literature that suggests the high latitude portion of the NPS isnearby, while lower latitude portions are more distant. Understanding the contributions of this localemission is critical to developing a complete model of the Galactic magnetic field.
Dunlap Astronomer discovers we may be surrounded by tunnel-like structure
(Oct.14, 2021)
Dr. Jennifer West, Research Associate at the Dunlap Institute for Astronomy and Astrophysics, is making a scientific case that two bright structures that are seen on opposite sides of the sky â previously considered to be separate â are actually connected and are made of rope-like filaments. This connection forms what looks like a tunnel around our solar system.
âIf we were to look up in the sky,â explains West, âwe would see this tunnel-like structure in just about every direction we looked â that is, if we had eyes that could see radio light.â
A Vast âMagnetic Tunnelâ May Surround Earth and Our Entire Solar System
(today)
An expert in magnetism in galaxies and the interstellar medium, West looks forward to the more possible discoveries connected to this research.
âMagnetic fields donât exist in isolation,â she says. âThey all must to connect to each other. So, a next step is to better understand how this local magnetic field connects both to the larger-scale galactic magnetic field, and also to the smaller scale magnetic fields of our sun and Earth.â
Spitzer steps aside
All Spitzer-related articles will be gathered together in an online collection.
An extremely energetic supernova from a very massive star in a dense medium
Here we present a new event, SN2016aps, offset from the centre of a low-mass galaxy, that radiated âł5âĂâ1051âerg, necessitating a hyper-energetic supernova explosion.
Voyager 2 shut off its instruments to save power, NASA says
Voyager 2 was only expected to last for five years, but it‘s still operating 42 years after launch.
Yet Saturday, the probe did experience a bit of a hiccup 11 billion miles from Earth, according to NASA.
„Magnetische Wand“ im interstellaren Raum
(04.11.2019)
âVoyager 2â hat die Grenze der HeliosphĂ€re in nur einem Tag passiert, was einen scharfen Ăbergang zum lokalen interstellaren Medium bedeutet. âDie alte, historische Vorstellung, dass der Sonnenwind sich einfach allmĂ€hlich reduziert, je weiter man in den interstellaren Raum vordringt, trifft nicht zuâ, erlĂ€uterte âVoyagerâ-Forscher Don Gurnett von der UniversitĂ€t von Iowa, Ko-Autor einer der Analysen. âWir haben mit âVoyager 2â und vorher mit âVoyager 1 gezeigt, dass es dort drauĂen eine ausgeprĂ€gte Grenze gibt.â