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By Daniel Fischer Every page present in Europe & the U.S.!
| Ahead | Awards 
The latest issue!
| A German companion! (SuW version) Current mission news: MGS (latest pictures!) + Cassini + Galileo + NEAR |
On April 25 it was at about 6.5 mag: estimates from ICQ & JPL, a SC story and coordinates.
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New Cosmic Microwave Background data show 2nd, 3rd peaks - and the right baryon number, tooThe next generation of Cosmic Microwave Background Radiation (CMBR) data released over the weekend has advanced cosmology another step: Now not only is the "first acoustic peak" in the angular power spectrum - that had shown up prominently in earlier balloon-based data, see Updates # 187 story 3 and 189 story 3 - is evident, but the 2nd and probably the 3rd peak are there as well. Both balloon experiments have been analysed more thorough now - and the first results from DASI, a radio interferometer at the South Pole, are also in. While the presence and position of the 1st peak confirm the overall flatness of the Universe and support inflation theory, the relative heights of the other two peaks seen by the three experiments contain information on other fundamental aspects, such as the number of baryons.The data released a year ago had been hailed widely, but there seemed to be a problem: The 2nd peak was "too low" to accomodate the established value for the cosmic baryon density. Astrophysicists were very confident that they understood the physics of nucleosynthesis shortly after the Big Bang, and together with recent measurements of esp. the amount of Helium-4 and Lithium-7 cooked up in the Big Bang a firm prediction of the amount of 'ordinary matter' aka baryons in the Universe had been made. Cosmology veterans like Mike Turner boldly predicted that it then would have to be the data that were wrong - and two of the three new spectra (from DASI and the BOOMERANG balloon) seem to show exactly that. The 2nd peak is higher indeed, just as earlier spectra from another ground-based interferometer, CBI, had indicated (see Update # 212 story 4). All three spectra now fit the current nucleosynthesis calculations and observations, and only the new MAXIMA analysis is still a bit at odds with them. The DASI (Degree Angular Scale Interferometer) as well as the BOOMERANG spectra indicate that 'ordinary; (baryonic) matter, the stuff of which humans, stars and galaxies are made, accounts for only 4.5 percent of the universe's total mass and energy. About eight times as much dark matter also exists in the universe, numerous astrophysical measurements show: "The DASI result strengthens the case that most of the mysterious dark matter is comprised of some new form of matter," says Mike Turner - and then there is the even more mysterious 'dark energy' to make the Universe flat overall. That correct prediction of the height of the 2nd peak shows how far cosmology has come these days - but the lack of understanding about the nature of both the dark matter and the dark energy also shows how far we still have to go. (Based also on a talk by K. Olive, at the Physics Inst. of Bonn University on April 27) |
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Signals received from Pioneer 10!After months of anticipation contact has been reestablished with a distant pioneer over 10 light-hours from Earth: A signal was sent to the spacecraft, which locked onto it and returned a signal to the Madrid Deep Space Network facility at 17:27:30 UTC on April 28. That was the first time since August 19 of last year that something was heard from the spacecraft! As of April 30 Pioneer 10 was 77.693 AU from the Sun and travelling at a relative speed to the Sun of 12.292 km/s. The probe's distance from Earth was 78.505 AU, with a round-trip Light Time of 21 hours 45. The probe is moving in a straight line away from the Sun at a constant velocity of about 12 km/sec.Power for the Pioneer 10 is generated by the Radioisotope Thermoelectric Generators (RTG's). Heat from the decay of the plutonium 238 isotope is converted by thermoelectric couples into electrical current. The electrical output depends on the hot junction temperature, the thermal path to the radiator fins, and the cold junction temperature. It is the degradation of the thermoelectric junction that has the major effect in decreasing the power output of the RTG. In the 27-year time scale operation of Pioneer 10, the 92 year half-life of the isotope does not appreciably affect the RTG operation. |
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Far side of the Sun now under regular surveillance!Since April 27 two teams of astronomers working with the SOHO spacecraft are providing data about the activity on the far side of the Sun to everyone on a regular basis: The SWAN instrument sees ultraviolet rays sweeping like a lighthouse beam across interplanetary gas beyond the Sun (see Updates # 136 small items and 186 story 4), while the MDI instrument peers right through the Sun to locate hidden sunspots and their active regions through helioseismology (see Update # 180). Anyone troubled by storms on the Sun will now have an extra week's early warning of eruption risks. The announcement of these new far-side services coincided with the celebration of Sun-Earth Day 2001 by ESA, NASA and other agencies.It also marked the fifth anniversary of the commissioning of the European-built SOHO, in April 1996, and the formal start at that time of the observations with a dozen sets of clever solar instruments. European and US scientific teams contributed the instruments to this project of international cooperation between ESA and NASA. The Sun takes roughly four weeks to turn completely around on its axis, but active regions can appear and grow in only a few days. So until two years ago, no one had any way of telling when an active region might come 'around the corner' - perhaps blazing away with eruptions as soon as it appeared. If an active region can be detected in the middle of the far side it will appear on the eastern side of the visible disk about seven days later. The SWAN team announced the telltale ultraviolet observations in June 1999, and in March 2000 it was reported that SOHO's MDI had detected sound waves affected by far-side sunspots. Speeded by the intense magnetic fields associated with sunspot regions, the sound waves arrived a few seconds early at the Sun's near-side face, compared with sound waves from sunspot-free regions. Decoding MDI data from a million points on the Sun's near side, to obtain an impression of the far side, uses a technique called helioseismic holography and requires a powerful computer. Both discoveries were made retrospectively from SOHO's archives, but since then the teams have streamlined their data gathering and analyses to the point where they can offer routine long-range forecasts of intense solar activity based on far-side foresight. |
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Growing grains detected in Orion Nebula proplydsThe HST has yielded the first direct visual evidence for the growth of planet "building blocks" inside dust disks around dozens of stars in the giant Orion Nebula, the nearest, large "star-factory" to Earth - but any fledgling planets must try to quickly "beat the clock" by forming before they are evaporated away by a blistering flood of radiation from the nebula's brightest star. This is the first time that large growing grains, which range in size from smoke particles to sand grains, have been seen in visible light in these protoplanetary disks: The dust we're seeing in the Hubble observations is large, completely unlike dust that we've seen in young star-forming regions like this before. The astronomers deduced the dust size from the way the disks allow light to pass through them. The fine dust normally seen in space scatters blue light but allows red light to pass through, but the dust disks in Orion appear gray because they allow all colors of light to pass through: This is unusual in space and can only be explained if the dust is much larger than interstellar dust. |
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The first Kuiperoid (other than Pluto) with a moonhas now been discovered: "Recovery images of the transneptunian object (TNO) 1998 WW31 [...] with the 3.6-m CFHT show that two objects were within less than 1.3 arc seconds and moving together over the two nights of observations (2000 Dec. 22 and 23 UT) without any detectable relative motion," reports an IAUC Circular - and that "CFHT public archive observations of the same field taken nearly a year previously" do show the Kuiperoid's moon as well, though not as clearly. The TNO there appears as "double or elongated on four images, with the two components at a different distance and position angle than on the discovery images. A very preliminary reduction shows the brighter component to be 0.4 mag brighter than the secondary in R on 2000 Dec. 22, with the secondary being 1.2 arc seconds from the primary." |
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ISS UpdateEndeavour is back on Earth after the most troublesome ISS visit so far; the latter has mostly ecovered from a still unexplained computer breakdown on Destiny, though, and the expensive Canadarm2 is safely installed. Meanwhile NASA and ASI have begun formal discussions on Italy providing a Habitation Module for the ISS, in exchange for astronaut flights and 'visibility', and even China is eyeing an entry into the ISS program. STS-100 MCC Status # 27, 26, 25, 24, 23, 22, 21, 20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, ISS Status # 10, STS-100 Releases by NASA, ESA (other version) and RSC Energia, Science@NASA on Canadarm2, a NASA Release on the Italian option (plus the document and a related Advisory).The STS-100 Status and Journal. Coverage of May 1: SN, SC, ST, SC, SD, CNN, AP, ST. April 30: ESA News, AN, SPIEGEL. April 29: ST, HC, SN ( earlier, still earlier), AN, SC, AP, AFP, SPIEGEL. April 28: JSR, SN (earlier), HC, ST, AP. April 27: ESA News, BBC, AN, ABC, SN, AFP, OS, CNN, ST, SC, SPIEGEL (andere Story). April 26: HC, AN, AP, BBC, SC ( earlier), USA Today, AFP (other story), AP, ST, SR, SN ( earlier, still earlier), RP, SPIEGEL. April 25: SN, CNN, HC, AN, SC, AFP, ST. April 24: SN, AN, HC, SC, AP, USA Today. April 23: HC, SR, CNN, BBC, AP, AFP (other story), SN, RP, SPIEGEL. April 22: CNN, AN, HC ( earlier), Ottawa C., SR, SC, SN, RP. April 21: SN, BBC, AN, HC ( earlier), CNN, SC, FT, RP, SPIEGEL. April 20: HC, NYT, AP, BBC, Ottawa Citizen, Edmonton Journal, OS, FT (other story), RP. April 19: Launch Pictures, SN, HC ( earlier), CNN, AN ( other story), BBC ( earlier), SC (other and earlier stories), AFP, SR, FT, OS, ST, SPIEGEL. April 18: CNN, AP, AFP, SC (other story). |
April 17:
JSC Status,
NYT,
ST,
SC,
HC,
AP.
April 16:
SN
(long preview),
SC,
FT,
HC,
AN.
April 15:
Interfax.
April 13:
FT,
CNN.
April 12:
SC.
The Uninvited has reached the ISS - Dennis Tito and the two cosmonauts have docked Soyuz TM-32 to the ISS just 14 hours after Endeavour had left. The Decision Paper of April 24 that gave Tito's ride some legal backing, related NASA, ESA (other version) and Energia releases, collected stories by SC and SR and coverage of May 1: CNN, BBC, AP, Reuters, AFP (other story), SC. April 30: pictures, HC, BBC, SD, SN, AP, ST, AN, SC ( other story and another one), Reuters, CNN (other story), CNNfn, RP, ZDF, SPIEGEL (früher). April 29: NYT, CNN, Reuters, AFP. April 28: Salon, Arabic News, BBC, OS, AFP (other story and another one), CNN, Reuters, SR, ST, SC ( other story), SN, SPIEGEL (früher). April 27: CollectSpace, SC, SN (earlier), ST, CNN (other story), BBC ( other story), Reuters, AP, NYT, AFP, RP. April 26: SN, CNN, SC, BBC, Reuters, Interfax, AFP, RP, SPIEGEL. April 25: SC, SN, NYT, OS, AFP (other story), RP. April 24: ABC, BBC, AN, SR, ST, CNN, SN (other story), SD, SC ( other story, a debate and an interview), SPIEGEL. April 23: AFP ( earlier), SC ( other story), BBC, OS. April 22: SPIEGEL. April 21: NYT, BBC, AFP, Reuters, WP. April 20: TIME, SC ( earlier), CNN (earlier), ST, AN, SD. April 19: SD, SC ( earlier). April 18: SN, SC, AP, RP. April 17: Interfax, BBC, HC, CNN, ST, AP, pictures. April 16: SD, CNN, AFP. April 13: SD. April 12: AFP. April 11: HC, SC. Russian dreams of a Mir 2 funded with foreign money: SC. And talk about Mars missions: The Times, Ananova. Details of the Mir crash: Zarya page. And an eye-non-witness report from a plane: YK's pages (and earlier impressions). Debris found in Fiji? NYT. Soyuz TM-26 for sale: Spacehab Release, BBC. 30 years ago: the launch of Salut 1, the 1st space station: SC. |
Microlensing "telescope" resolves disk of distant starA rare microlensing event by a binary star has allowed astronomers with the VLT to take spectra of different well-defined spots on the disk of a distant star: ESO Press Release, BBC, RP (which didn't get it ...).Doubts about White Dwarfs as major inhabitants of the galactic halo (see Update # 221 small items) are being raised by Gibson & Flynn: There could be something quite wrong with the math ... Two more candidate groups for the mysterious EGRET sources (see also last Update small items) are AGNs and galaxy clusters. THEMIS snaps Earth and MoonNASA's 2001 Mars Odyssey spacecraft turned its multipurpose camera homeward last week and took its first picture, a shot of a faint crescent Earth: JPL Release, PIA ... 558 and 559, SN, SPIEGEL. Earlier: JPL Release.Perfect Odyssey orbit makes TCM unnecessary - due to a favorable launch trajectory, flight controllers for Mars Odyssey have decided that they can postpone the first maneuver to fine-tune the spacecraft's flight path: Mission Status, CNN. Mars Scout ideas - NASA intends to use Mars Scouts to complement its core missions already on the books: SC. Mars Czar steps down: NASA Release. Mars Society of Germany proposes a Mars Balloon Mission, a super-pressure balloon would float for up to 100 days over the Martian surface and collect a vast quantity of scientific data: Press Release. NASA outfits Palomar Schmidt for asteroid huntingAsteroid search efforts got a boost from a new, improved camera now installed on the famous 1.2-meter Oschin Schmidt telescope at the Palomar Observatory: JPL Release, SC, Astronomy.What we've learned from the Oct. 2000 low flyover over Eros by NEAR is being discussed in Science - "the majority of the small features that make up the surface of asteroid Eros more likely came from an unrelenting bombardment from space debris than internal processes": JHU APL Press Release, SC. Muses-C target a reddened ordinary chondrite, IR spectra of asteroid 1998 SF36 show: IAUC.
Speculation blames twists in human evolution on cosmic impactsA British anthropologist and an Australian impact statistician believe that repeated impacts have wiped out all lines of human evolution other than Homo sapiens, which survived by sheer luck (and not superiority) - this scenario has already been dismissed widely: Liverpool Press Release, coverage by BBC, SC and early debate in CCNet of April 26 (item 7).Medieval witnesses did not see an impact on the Moon - the idea that what humans witnessed and chronicled in A.D. 1178 was a major impact that created the 22-km lunar crater called Giordano Bruno is myth: UA Press Release [SN], Science@NASA, BBC, WO. Turning asteroids into weapons is possible, say British astronomers: The Times, Daily Telegraph. MAXUS-4 sounding rocket experiences great flight, hard landingThe ESA Maxus-4 microgravity mission was successfully launched on 29 April, but the parachute recovery system, activated 6 km above the ground, did not deploy properly, and the payload package was badly damaged on impact with the ground: ESA News. |
Moon's dark side yields clues to Earth's climateScientists have revived an old technique for monitoring Earth's climate by carefully observing "earthshine," the ghostly glow of the dark side of the Moon - earthshine measurements are a useful complement to satellite observations for determining Earth's reflectance of sunlight, an important climate parameter, and long-term observations thus monitor variations in cloud cover and aerosols: AGU Press Release [SN], NSU, NYT, SC, Astronomy, RP.Solar sail damaged in accidentAn accident during pre-launch checkout and testing has damaged the spacecraft intended to test the deployment of the solar sail for the Planetary Society's Cosmos 1 Mission (see Update # 219 story 2) - so there was no launch on April 26: Plan. Soc. Press Release, coverage by SC, SN, ST, AP.GSLV flies in 2nd attempt!India successfully launched its most advanced rocket on April 18, lofting an experimental communications satellite from a coastal space port 20 days after its maiden launch was aborted: ISRO Press Release, Homepage, SD, SN, BBC, SR, AFP, AN, Kyodo, SPIEGEL. Earlier: Interfax, AFP.The satellite didn't quite reach geostationary orbit, though, making some planned experiments impossible: Press Release, AN, AFP. "Space Race runners-up", incl. India: Economist. Comeback for the X-33?The cancelled X-33 shuttle prototype could re-emerge as an Air Force project, NASA and Air Force officials have confirmed - the USAF is talking with NASA about keeping the program on fiscal life-support through the end of the year: SC, FT, OS, ST, WP.German RLV pre-demonstrator approved: Astrium Press Release. More European RLV trends: SR. The X-43A could make first scramjet hypersonic flight in mid-May, the first time a non-rocket propelled, air-breathing engine will power a vehicle in flight at hypersonic speeds, though just for a few seconds: NASA, Orbital Releases, Homepage, coverage by CNN, BBC, FT, AN, SC, AP, Reuters, SPIEGEL, RP. Captive-carry dress rehearsal flight successful: DFRC Press Release. Gagarin, shuttle anniversaries celebrated40 years of space collectibles: CollectSpace. Both anniversaries: CNN. 40 years after Wostok 1: APOD, AP, CNN, BBC, ABC, SPIEGEL, RP. 20 years after STS-1: APOD, Florida Today, Huntsville Times, Orlando Sentinel. How Columbia is today: FT. The future of the shuttle: SC.
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Compiled and written by Daniel Fischer
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