Tag: spaceflight

India aims to double launches in 2018

4:39 pm

The new colonial movement: The head of India’s space agency ISRO said in a newspaper interview today that the agency hopes to more than double the number of launches it completes in 2018, increasing the number to between 10 to 12 launches from the four successful launches in 2017.

“We are targeting 10 to 12 launches next year. The communication satellite GSAT-6A and Chandrayaan-2 mission will be launched by GSLV-Mk-II rockets. The second mission of GSLV-Mk-III rocket with a communication satellite and the launch of navigation satellite also will take place next year”, Kiran Kumar explained.

The much-awaited Chandrayaan-2 mission could be launched in the second quarter of 2018. “The moon lander is ready for the mission and undergoing tests. The flight hardware is getting assembled and going through tests. We are targeting the second quarter of the next year for the launch”, the top scientist said.

The two GSLV launches are critical, as this larger rocket is needed for India to really compete in the international market.

Leave a comment

The SpaceX light show yesterday

9:12 am

Falcon 9 launch, December 22, 2017

Numerous news articles today have noted that last night’s launch by SpaceX of ten Iridium satellites produced a somewhat unusual light show for Californians. Reader Frank Kelly sent me some images he took, noting,

I was able to catch the booster ascent, stage separation, second stage burn and what looks like the booster spinning with at least one engine firing. The spinning went on for a while so it must have had some fuel left.

I read SpaceX said they would not land this booster so maybe they had some fun with it for us folks in LA. It spun around for a minute like a pinwheel. A great show.

close-up of first stage maneuvers

The image above right is one of his images, reduced in resolution to post here. Below that is a cropped section of the full resolution image, showing the “pinwheel” being performed by the first stage. And as other readers of BtB have also noted, the launch crew was clearly performing engine tests and maneuvers with this first stage, all the way down to the ocean.

As is typical of SpaceX, they waste no opportunity to test their equipment and find out what it can do, on the extreme. I suspect these maneuvers were designed to push the first stage’s ability to recover from an out-of-control spin. From the call-outs by engineers during the launch, it appears that this test was a success, as it appears from those call outs that the first stage “landed” properly upright in the ocean.

Let me add that in reviewing some of the youtube videos posted by my readers in the comments below, I also think these first stage maneuvers might be tests in preparation for the first Falcon Heavy launch, which will involve landing three first stages at the same time, two landing very close together at Kennedy. The flight tests yesterday could be an effort to demonstrate how well they can program those first stages for their return.

16 comments

SpaceX successfully launches 10 Iridium satellites

7:45 pm

Capitalism in space: SpaceX today successfully launched ten 10 Iridium satellites.

This launch for Iridium reused a first stage from a previous Iridium launch. This was the first time Iridium launched with a used first stage. SpaceX did not try to recover the stage, which could be for several reasons, including the possible desire by the customer that they devote their entire effort to getting the satellites in orbit.

This was also SpaceX’s last launch for the year. The launch standings for the year now are thus:

29 United States
19 Russia
18 SpaceX
15 China

Sometime in the first week of 2018 I will post a full table showing this year’s launches plus the launch totals going back to the early 1980s. It reveals a great deal about the history of the launch industry for the past half century, as well as where that launch industry is likely heading in the coming half century.

11 comments

Russia to launch luxury hotel room module to ISS?

12:11 am

Capitalism in space: Roscosmos is considering a plan to launch a hotel module to ISS where it could house tourists for profit.

According to a detailed proposal seen by Popular Mechanics, the 20-ton, 15.5-meter-long module would provide 92 cubic meters of pressurized space. It would accommodate four sleeping quarters sized around two cubic meters each and two “hygiene and medical” stations of the same volume. Each private room would also have a porthole with a diameter of 228 millimeters (9 inches), while the lounge area of the module would have a giant 426-millimeter (16-inch) window.

The external structure of the tourist module looks like the Science and Power Module, NEM-1, which Russia is currently building for the International Space Station. The second NEM module had originally been on the books in the station’s assembly scenario, but the Russian government funded only one module. It will serve primarily as a science laboratory and a power-supply station for the ISS.

Now, Russia’s prime space station contractor, RKK Energia, came up with a scheme to pay for the second NEM module through a mix of private and state investments. To make profit, the NEM-2 would be customized for paid visitors.

Makes sense to me. Russia doesn’t really have the money right now to fund a big deep space exploration program. Better they aim for profits in space, as that will keep them in the black and provide them the capital they presently lack.

16 comments

Japan’s Google Lunar X-Prize rover arrives in India for launch

12:07 am

Capitalism in space: The rover being built by the Japanese team competing for the Google Lunar X-Prize has arrived in India for installation on the PSLV rocket that will launch it into space.

The Sorato rover which is flight ready will be mounted on Team Indus lander at its facility in Jakkur. HAKUTO, one of the five teams competing for the Google Lunar XPRIZE, has signed a ride share agreement with Team Indus (India’s first private aerospace startup) for launching the Sorato along with the Indian rover.

Team Indus’s spacecraft, along with the two rovers, will also carry a few payloads and will be launched onboard ISRO’s workhorse, the PSLV-XL. The launch is expected to take place early next year (before March 8, 2018, the date set by Google to the five privately funded teams to launch the landers and the rovers on the Moon surface).

Several important details here. First, though the Japanese team appears to have all the necessary funds to pay for their flight, Team Indus is still searching for investment, and might not have the money to pay for its share of the flight. What will happen in that case is unclear.

Second, the word Hakuto in Japan means “white rabbit.” This name was chosen because Japanese folklore says a rabbit can be seen in the dark areas of the Moon’s face. This makes Japan’s rover the second rabbit to fly to the moon, after China’s Yutu rover, which in English means “jade rabbit” a name also based on Chinese folklore.

2 comments

China’s 2017 year in review

11:09 am

Link here. The review summarizes every significant achievement and failure that occurred in the Chinese space industry in the past year. Unfortunately, it provides no further information of the cause of the launch failure of Long March 5 in July, nor when that rocket, China’s biggest, will resume launches.

The article also summarizes China’s long term plans as released earlier in the year. This quote struck me as most interesting:

The main contractor for the Chinese space programme, the China Aerospace Science and Technology Corporation (CASC), set out a space transportation roadmap in November. These targets include flying the low-cost Long March 8 by 2020, development of a reusable space plane by 2025, and super heavy-lift launch vehicle, referred to as the Long March 9, to make its maiden flight by 2030.

2035 is the target for full reusability for its launch vehicles, while 2040 is marked for developing next-gen launch vehicles capable of multiple interplanetary round-trips, exploiting space resources as well as a nuclear-powered space shuttle.

I don’t know if China will achieve these goals, but I do know that it intends to try, and that this effort guarantees that the 21st century will be the century where what I call the new colonial movement will take flight, with many nations on Earth pushing and succeeding in the establishment of viable bases on other worlds.

One comment

Musk releases pictures of assembled Falcon Heavy in hanger

9:40 pm

Falcon Heavy in hanger

Capitalism in space: Elon Musk today tweeted several pictures of the Falcon Heavy rocket, assembled in its hanger at Cape Canaveral and awaiting roll out for its first static fire tests on the launchpad.

As I will have nothing to do with Twitter, I must thank reader Michael Phillips for emailing me the photos. The one of the right I think shows the most detail. Note that the two side stages are previously flown Falcon 9 first stages. Only the central core has not flown before. According to previous reports, it required significant redesign to work in this configuration.

There is as yet no word on exactly when the roll out and launchpad static fire tests will take place, but all indications suggest it will be very soon. Whether the launch itself will follow several weeks later, as the link above says and has been stated many times by SpaceX, is more questionable. Remember, they have never fired all 27 engines of the threefold first stage at the same time. I am expecting that they will need time to review the data from that static fire test. I would be very surprised if their analysis and any changes it calls for will be doable in only a few weeks.

7 comments

Two finalists for 2020 deep space planetary mission picked by NASA

1:16 pm

NASA has narrowed its choice for a 2020s deep space planetary mission to two finalists, either a sample return mission to Comet 67P/C-G or a drone that would fly through Titan’s atmosphere.

The sample return mission sounds very doable with today’s technology. The Titan drone mission however is far more intriguing.

Dragonfly is a dual-quadcopter lander that would take advantage of the environment on Titan to fly to multiple locations, some hundreds of miles apart, to sample materials and determine surface composition to investigate Titan’s organic chemistry and habitability, monitor atmospheric and surface conditions, image landforms to investigate geological processes, and perform seismic studies.

If it was up to me and I had unlimited funds, I’d go with Dragonfly. We know far less about the outer solar system, and this mission would be an ideal way to increase that knowledge. It is also far more daring, which carries the risk that the costs to build and launch will rise uncontrollably.

One comment

World View balloon explodes

9:42 am

Capitalism in space: A World View balloon exploded at its launch facility in Tucson yesterday.

No injuries were caused when a large, tethered test balloon ruptured as crews deconstructed it after a successful ground test to fill the balloon, World View spokesman Andrew Antonio said. The rupture resulted in a loud sound heard in the area, and a small fire on the balloon, he said. “We have reached out to reassure our immediate neighbors,” Antonio said. “There were no injuries and only superficial facility damage at the site.”

World View says it can use either helium or hydrogen gas to fill its stratospheric balloons but has initially been using hydrogen, which company officials have said is safe when handled properly.

World View also released its first images from a Stratollite balloon flight yesterday.

I think the second link demonstrates clearly that Stratollite is a good concept for high altitude reconnaissance. I think the first link demonstrates that hydrogen is still problematic for high altitude balloons.

One comment

Virgin Galactic signs deal with Italy for dedicated research flight

9:28 am

Yawn. Virgin Galactic has announced that it has signed a deal with Italy for a future SpaceShipTwo research flight.

I feel obliged to report this, but am also very skeptical about it. They have still not performed any powered flights with their new ship, Unity. And their last glide test was four months ago. They state that they will have a full test flight program in 2018, but we have heard that story so many times before we’d all be silly to believe them now.

When they start flying, I will start taking them seriously again. Not before.

Leave a comment

Smallsat industry considering standardized “launch unit”

9:18 am

Capitalism in space: The emerging smallsat industry is considering establishing a standard “launch unit,” similar in concept to the standardized container system used by the shipping industry on Earth, to ease payload scheduling and installation on rockets.

“Developing a standard Launch Unit, or Launch-U, for mid-sized smallsats — approximately the size between a toaster and a small refrigerator — will enable rideshares to be configured more quickly and efficiently, resulting in more launch opportunities at a lower cost,” Aerospace representatives said in a statement. “Aerospace [Corporation] is driving the Launch-U conversation by assembling representatives from industry, academia and government to set the mid-size smallsats standard.”

For example, this standardized container concept would make it easier for a smallsat to switch launch rockets should its initial ride get delayed.

The industry has already attempted some standardization with the cubesat idea, which universities have been using now for several decades, a standard-sized satellite structure that is ten centimeters to a side. This launch unit concept would add the standardization to the launch vehicle, creating a standard slot within rockets that could easily take on new satellites.

3 comments

Blue Origin still a year away from launch humans on New Shepard

9:09 am

Capitalism in space: Blue Origin revealed yesterday that it will still be a year at least before they start flying humans on their suborbital New Shepard spacecraft.

The company plans to later fly humans, both as payload specialists for human-tended experiments as well as on tourist flights. Those flights, though, are still at least a year away. “We’re probably a year and a half, two years out from when we’re actually able to fly tended payloads,” Ashby said. “We’re about roughly a year out from human flights, depending on how the test program goes. We have a bunch more tests to do, and we’re going to fly some human test flights before we put paying people in the rocket.”

Previously they had suggested they would be flying humans much sooner, possibly this year. Despite this new delay, last week’s test flight did include Blue Origin’s first paying customers, and the company indicated that they have sold space on all their upcoming unmanned test flights, and that their manifest for those upcoming flights is essentially full.

Though I know many disagree with me, I am increasingly doubtful there will ever be a viable suborbital tourist business. Once commercial orbital manned flights become available, I don’t see there being much profitable interest in such short suborbital experiences. The cost will be too high in comparison with the payoff. And it appears that those commercial orbital manned flights are going to be arriving at about the same time as New Shepard’s first manned flight.

5 comments

Algeria’s space agency reveals its plans for the next two decades

8:46 am

The new colonial movement: With the successful launch by China of its first geosynchronous satellite (mostly built by China as well), the Algerian space agency has revealed its preliminary plans through 2040.

Algeria plans to send several state-of-the-art satellites as part of its space programme 2020-2040, which is “under study now,” the director general of the Algerian Space Agency, Azzedine Oussedik, said on December 18, 2017, in Algiers.

A national space programme, which includes plans for the launch of many cutting-edge satellites, is under consideration at the Algerian Space Agency, Oussedik told a news conference about the successful launch, on December 11, 2017, of the Algerian space communication satellite Alcomsat-1 from the Chinese launch site at Xichang.

He added that the new programme will be put into operation after the completion of the current national space programme 2006-2020, under which five satellites have been successfully launched, the latest of which is Alcomsat-1.

There really isn’t much of an Algerian space program. China built this first satellite, and I suspect that most of the remaining four satellites planned under the current program will be built by foreign companies also. Essentially, this announcement is Oussedik is pushing for government funds to sustain his office into the future. It might serve Algeria to have its own satellites, but from my perspective this is not how to do it.

Leave a comment

Mars rover update: December 18, 2017

11:44 am

Summary: The scientists and engineers of both Curiosity and Opportunity have route decisions to make.

Curiosity

null

For the overall context of Curiosity’s travels, see Pinpointing Curiosity’s location in Gale Crater.

Since my November 16 update, Curiosity’s travels crossing Vera Rubin Ridge, a geological bedding plain dubbed the Hematite Unit, has continued apace. They however have not been following the route that had been planned beforehand, as shown by the yellow dotted line on the right. Instead, they have headed south, along the red dotted line. For the past week or so they have been doing a variety of research tasks in the same area, analyzing samples taken months before, studying sand deposits, and taking many images of some interesting rock layers.

I also suspect that the lack of movement in the past week is partly because they need to make some route-finding decisions. The planned yellow route shown above appears to be somewhat rough in the full resolution orbital image. While I suspect they will still head in that direction, I also think they are doing some very careful analysis of this route and beyond, to make sure they will not end up in a cul de sac where the rover will not be able to continue its climb of Mount Sharp.

Opportunity

For the context of Opportunity’s recent travels along the rim of Endeavour Crater, see my May 15, 2017 rover update.
» Read more

3 comments

ArianeGroup to begin production of first Ariane 6 rocket

9:34 am

Capitalism in space: Having completed a new review of the design of its new Ariane 6 rocket, ArianeGroup and ESA have decided to begin production for a planned launch in 2020.

I continue to wonder how they expect this expendable rocket to compete for launch business with both SpaceX and Blue Origin flying reusables by 2020. At best, I see the member states of the European Space Agency saddled with the requirement to use this more expensive rocket, which will seriously handicap them in the competition to settle the solar system.

5 comments

Giant Stratolaunch plane conducts first taxi test

9:24 am

Capitalism in space: The giant Stratolaunch plane built out of two 747s completed its first taxi test yesterday.

Stratolaunch’s plane, nicknamed Roc, has the widest wingspan in the aviation world at 385 feet. That’s 50 percent wider than the wings of a Boeing 747 — which probably shouldn’t be surprising, considering that parts from two 747s went into building the plane. Mojave-based Scaled Composites aided in the fabrication of the plane’s carbon composite components.

I think a better way to illustrate the size of the wingspan is to note that if you laid a Saturn 5 rocket along those wings, it would not reach the tips at either end, being “only” 363 feet long.

Several experienced engineers at Behind the Black have previously wondered at whether the plane’s central structure holding its two fuselages together would be strong enough to provide a stable flight. Looking at the picture at the link, I must wonder the same thing.

3 comments

XCOR bankruptcy revelations

9:06 am

XCOR’s bankruptcy has revealed how far the company was from actually building and flying its Lynx suborbital spacecraft.

In original financial filings, XCOR reported having $1,424.66 in cash.

No value was given to the Lynx MK1, a spaceplane in development that would take off and land horizontally. Between $15 million and $20 million would be required to finish the Lynx, according to documents. An estimated $25 million to $30 million was invested.

It is hard to say whether XCOR was a scam, or a good idea that simply never could get the investment capital to fly. In the end, however, it essentially turned out to be both. According the article, local government agencies in both Florida and Texas have lost millions from investments they made in the company in the hope it would produce jobs in their communities.

11 comments

Soyuz launches new crew to ISS

8:52 am

The Russians today launched a new crew to ISS using their Soyuz rocket.

Since the capsule only has to fly to ISS in low Earth orbit, it did not use the Fregat upper stage that failed in another recent Soyuz launch.

This launch probably clinches Russia’s lead over SpaceX for the most successful launches in 2017. At the same time, the U.S. overall will still win handily, with its most total launches in this century.

28 United States
19 Russia
17 SpaceX
15 China

I will be publishing a complete table of the launches with analysis, as I did last year, once the year is complete.

Leave a comment

SpaceX launches Dragon and lands 1st stage

11:48 am

Capitalism in space: SpaceX this morning successfully launched a previously used Dragon cargo freighter to ISS as well as once again successfully landing the previously used first stage.

This was the first time NASA agreed to the use of a previously launched first stage. With the first stage and capsule both reused, only the second stage and one out of 10 Merlin engines was new and will not be available for further reuse.

I have embedded the launch video below the fold.

The standings for the most launches in 2017, as of today:

28 United States
18 Russia
17 SpaceX
15 China

Note that I am counting Soyuz launches for Arianespace out of French Guiana under Arianespace, not Russia. Also, the U.S. total includes SpaceX. I have separated SpaceX out to show how a single American company is competing aggressively with whole nations.
» Read more

6 comments

India to build a smallsat rocket

9:55 am

Capitalism in space: India’s space agency ISRO has announced that it developing a smallsat rocket expressly designed to launch cubesats and thus compete with the new smallsat rocket companies now about to become operational.

ISRO has been very successful in providing a launch platform for smallsats on its PSLV rocket, but in this case the smallsats fly as secondary payloads, dependent on the needs of the larger primary satellite. It appears that the space agency has realized that their market share in this area is now threatened by the small rockets being developed by Rocket Lab and Vector, and is therefore moving to compete.

This announcement also provides more evidence that the space industry is splitting between smaller unmanned payloads and larger manned payloads. I predict that in ten years most unmanned satellites launched to circle the Earth will be tiny and launched on tiny rockets, while simultaneously we will see a new generation of giant rockets putting manned spacecraft into orbit and beyond.

3 comments

Israeli X-Prize team still short of funds

9:41 am

Capitalism in space: The Israeli Google Lunar X-Prize competitor, SpaceIL, still needs to raise $7.5 million by December 20th or it will be forced to drop out of the competition, even though they say their spacecraft is finished.

SpaceIL initially estimated it would need about $8 million for the GLXP effort, but costs soared to $85 million, team members said. The team needs to raise $30 million by Dec. 20 to pay its bills. It has secured $22.5 million in pledges, contingent on the team’s ability to raise that additional $7.5 million.

I must admit that something about this stinks. Their budget has gone up more than ten times from its original estimate, from $8 million to $85 million. They have so far raised $55 million of hard cash, which is still about seven times their original budget, and with this they have actually built their spacecraft. Why do their need another $30 million? And why the hard December 20th deadline or they shut down?

As I say, something about this situation doesn’t feel right to me.

One comment

More than 1,000 sign up to compete for four UAE astronaut positions

9:32 am

The new colonial movement: More than 1,000 people have signed up to compete for four United Arab Emirate (UAE) positions as astronauts.

Those chosen will undergo three years of training in order to prepare them for a trip to ISS. The article does not say how the UAE will get them there, but I suspect at some point the country will sign a contract with either Russia, Boeing, SpaceX, or China for a seat on one of their manned capsules.

Leave a comment

Vector gets launch contract

9:24 am

Capitalism in space: The smallsat rocket company Vector has signed a launch contract with Astro Digital.

Vector, a nanosatellite launch company comprised of new-space and enterprise software industry veterans from SpaceX, Virgin Galactic, McDonnell Douglas, Boeing, Sea Launch and VMware, today announced that it will join forces with Astro Digital, a leader in real-time satellite imagery data, to conduct a dedicated launch in 2018 featuring one of Astro Digital’s satellites for remote sensing applications. Astro Digital plans to engage Vector to launch at least twelve such satellites as part of a larger constellation, with an option to then continue operations at a pace of two to four dedicated satellite launches per year.

The press release notes that Astro Digital flew a test payload on Vector’s suborbital test flight on one of Vector’s two test flights, and that experience convinced the company to sign this new contract.

Leave a comment

A variety of geological activity caused bright areas on Ceres

10:33 am

Occator Crater

Based on the data obtained of Ceres from Dawn scientists have concluded that a variety of geological activities caused the bright areas on the planet, and that some of those activities could still be happening today.

Since Dawn arrived in orbit at Ceres in March 2015, scientists have located more than 300 bright areas on Ceres. A new study in the journal Icarus, led by Nathan Stein, a doctoral researcher at Caltech in Pasadena, California, divides Ceres’ features into four categories.

The first group of bright spots contains the most reflective material on Ceres, which is found on crater floors. The most iconic examples are in Occator Crater [shown in the image above, reduced and cropped to post here], which hosts two prominent bright areas. Cerealia Facula, in the center of the crater, consists of bright material covering a 6-mile-wide (10-kilometer-wide) pit, within which sits a small dome. East of the center is a collection of slightly less reflective and more diffuse features called Vinalia Faculae. All the bright material in Occator Crater is made of salt-rich material, which was likely once mixed in water. Although Cerealia Facula is the brightest area on all of Ceres, it would resemble dirty snow to the human eye.

More commonly, in the second category, bright material is found on the rims of craters, streaking down toward the floors. Impacting bodies likely exposed bright material that was already in the subsurface or had formed in a previous impact event.

Separately, in the third category, bright material can be found in the material ejected when craters were formed.

The mountain Ahuna Mons gets its own fourth category — the one instance on Ceres where bright material is unaffiliated with any impact crater. This likely cryovolcano, a volcano formed bythe gradual accumulation of thick, slowly flowing icy materials, has prominent bright streaks on its flanks.

The report is somewhat vague about why they think that there might be some geological activity even today.

The image above, released as part of this press release, gives us a simulated oblique look at Occator Crater and its bright areas. It is definitely worth it to look at the full resolution image.

3 comments

Sea Launch will assemble rockets in U.S.

10:14 am

Capitalism in space: S7, the Russian company that now owns Sea Launch, announced today that it plans to assemble its rockets in United States.

This means the dock for the floating launch platform will remain in California. The article also indicates that S7 will continue to use Ukrainian Zenit rockets, which the platform was designed for, despite the desire of the Russian government to cut off all dependence on Ukrainian technology. There is also this tidbit:

The S7 company, which is about to resume the Sea Launch program, has enough clients, S7 Group co-owner and chair of the board of directors Natalia Filyova told the press. “We have [launch] orders, there is a long line [of clients], and we offer a good price. We are expecting revenue, but this will not happen right away. We will be investing heavily but we realize that we will make money,” Filyova said.

No details of the clients or the launch schedule were announced, however, so I remain skeptical. Meanwhile, Roscosmos announced today that it is negotiating with Boeing for future space tourism flights. This second story is directly related to Sea Launch, but you would only know this if you read Behind the Black. To pay off Boeing, which used to be a half partner in Sea Launch and was owed $320 million by the Russians, Roscosmos gave Boeing an unspecified number of seats on future Soyuz capsules to sell to others. Two of those seats were sold to NASA.

These new negotiations probably are an effort to arrange further sales for Boeing to help it get its money back. Boeing’s lawsuit for that money has placed a lien on the Sea Launch platform, and until its concerns are satisfied, S7 really can’t begin operations.

One comment

Negotiations underway to shift 1st stage landings at Kennedy to new site

9:58 am

Capitalism in space: Negotiations between the Air Force, NASA, and Space Florida (which runs the spaceport) have begun to establish a new location at Kennedy for 1st stage rocket landings.

The goal would be to lessen the burden landings impose on the Cape’s nearby industrial area, which workers must evacuate for hours during some missions. “If we have to stop operations for a launch during the middle of day, it is severely impacting to other customers,” Brig Gen. Wayne Monteith, commander of the Air Force’s 45th Space Wing, said Tuesday during a transportation conference at Port Canaveral.

As outlined in KSC’s master plan, the new landing pad could be built near the northern end of the spaceport’s secure perimeter — north of pad 39B and south of State Road 402 leading to Canaveral National Seashore’s Playalinda Beach. “We have land further to the north that’s not populated like the industrial area of the Cape is, and that might make for a really good location for a new landing zone for an increased landing rate,” said Nancy Bray, KSC’s director of spaceport integration and services.

I expect that SpaceX, should it be forced to shift landings from its just built landing sites, will also need to be in these negotiations since it will likely want some reimbursement for that work.

3 comments
1 … 253 254 255 256 257 … 434